WO2000036414A1 - Methods and products for peptide-based dna sequence characterization and analysis - Google Patents

Methods and products for peptide-based dna sequence characterization and analysis Download PDF

Info

Publication number
WO2000036414A1
WO2000036414A1 PCT/US1999/030104 US9930104W WO0036414A1 WO 2000036414 A1 WO2000036414 A1 WO 2000036414A1 US 9930104 W US9930104 W US 9930104W WO 0036414 A1 WO0036414 A1 WO 0036414A1
Authority
WO
WIPO (PCT)
Prior art keywords
sequence
polypeptide
dna
fragment
deficiency
Prior art date
Application number
PCT/US1999/030104
Other languages
French (fr)
Inventor
Jonathan W. Jarvik
Original Assignee
Sequel Genetics, Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sequel Genetics, Incorporated filed Critical Sequel Genetics, Incorporated
Priority to EP99968909A priority Critical patent/EP1151296A4/en
Priority to AU27107/00A priority patent/AU2710700A/en
Priority to CA002355134A priority patent/CA2355134A1/en
Publication of WO2000036414A1 publication Critical patent/WO2000036414A1/en
Priority to US09/788,268 priority patent/US20020155445A1/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/68Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
    • C12Q1/6869Methods for sequencing
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/68Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16BBIOINFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR GENETIC OR PROTEIN-RELATED DATA PROCESSING IN COMPUTATIONAL MOLECULAR BIOLOGY
    • G16B30/00ICT specially adapted for sequence analysis involving nucleotides or amino acids

Definitions

  • This invention relates to the fields of Molecular Biology and Genetics, with particular reference to the identification and analysis of DNA molecules. BACKGROUND
  • the fragment may be derived from genomic DNA of viral, procaryotic or eucaryotic origin, or it may be a derived from cDNA. In many cases, the fragment derives from a larger DNA molecule, or set of molecules, whose sequence
  • a number of methods presently exist for determining the nucleotide sequence of a DNA fragment involves cloning the fragment in a plasmid vector of known sequence, purifying the plasmid DNA, annealing a primer complimentary to a portion of the known sequence to one strand of the molecule, extending the primer with DNA polymerase, terminating the polymerization with dideoxy nucleotides, and comparing the lengths of the various terminated molecules to reveal the nucleotide sequence 3' to the primer.
  • SSCP single strand conformational polymorphism analysis
  • EMD nuclease analysis
  • ASO allele-specific oligonucleotide hybridization
  • an exon is assayed for chain termination mutations by PCR-amplifying the exon, expressing it in a cell free transcription/translation system, and examining the expressed polypeptide by SDS polyacrylamide gel electrophoresis to determine if it is smaller than a non-mutant control polypeptide. While the protein truncation assay can reveal the presence of a nonsense or frameshift mutation, it is important to note that the assay does not reveal the molecular nature or exact location of the mutation - one does not know if it is a TAG, TGA, TAA or frameshift mutation, and one only knows the approximate location of the mutation within the exon.
  • the database search activities in the prior art are aimed at protein identification and/or analysis
  • the search activity is aimed at DNA identification or analysis.
  • the artificial hybrid peptides that are analyzed in the instant invention are not naturally occurring, nor are they necessarily biologically active. And yet they have distinct utility as reporters that carry information about the nucleic acids that encode them.
  • peptide reporters provides a number of clear advantages over analysis of the DNA sequences that encode them.
  • One advantage derives from the fact that a peptide is considerably smaller than the DNA that encodes it (individual amino acids averages about 110 Da each whereas the trinucleotides (triplets) that encode them average over N Daltons each) .
  • Another advantage derives from the fact that peptides are much more diverse in composition than nucleic acids, as they are composed of combinations of 20 different amino acids instead of combinations of 4 different nucleotides.
  • the DNA to be analyzed is incorporated into a hybrid artificial gene that is then transcribed and translated to produce a hybrid peptide. Analysis of the peptide, rather than analysis of the DNA, is used to gain sequence data about the DNA.
  • the mass and/or composition and/or partial or complete amino acid sequence of the hybrid peptide is determined, and the data are used to search for matches in data sets produced by in silico transcription and translation of hybrid artificial genes created in silico using the reference sequence, or using transformations of the reference sequence such as single nucleotide deletions or substitutions thereof.
  • This peptide-based approach to DNA sequence-determination is fundamentally different from all other methods in the art, none of which employs transcription, translation and peptide analysis, as does the instant invention.
  • the invention depends on means to translate a portion of the unknown sequence as part of a fusion peptide whose synthesis originates in the known sequence and extends into the unknown sequence that is being characterized.
  • the unknown sequence need not comprise actual protein-coding sequence in the cell from which it originates, although it may in some cases, and so the invention is of general applicability and not confined to coding sequences.
  • the invention also depends on means to accurately measure the mass and/or composition and/or partial or complete amino acid sequence of the fusion peptide. Many methods for making such measurements are known in the art, and a number of them will be discussed later in this specification. But first, let us consider the issue of the expected sizes, masses, and amino acid sequences of the peptides that can be translated from an unknown sequence.
  • the likelihood that the first codon in the sequence is a nonsense codon (and that the peptide will thus be zero amino acids in length) is 1/21, or -4.7%.
  • the likelihood that the first codon is not a nonsense codon and the second codon is a nonsense codon (and that the peptide will thus be one amino acid in length) is 20/21 x 1/21, or -4.5%.
  • the likelihood that the first and second codons are not nonsense codons and the third codon is a nonsense codon
  • the table below shows the calculated probabilities, for the first 24 codons of a random DNA sequence, that a given peptide will be of a given length or less.
  • the table indicates that, for example, 0.705
  • the probability that a sequence of a given length translated from it will have a particular amino acid sequence can be calculated simply by multiplying together the frequencies in the genetic code of the codons encoding each amino acid amino acid in the sequence. Since some amino acids have as many as six codons and others as few as one, the predicted frequency will vary depending on the amino acid sequence itself. Thus the sequence LRRLLR, made up entirely of six-codon amino acids, will appear at a frequency of 1 in (6/61)6, or approximately once in one million codons, and the sequence MWWMMW, made up entirely of one-codon amino acids, will appear at a frequency of 1 in (1/61)6, or approximately once in fifty billion codons.
  • the number of distinct amino acid combinations and their frequencies is represented by the polynomial expansion (a+b+c+d+ +q+r+s)N, where the letters "a" through “s” (19 letters) represent the frequencies in the genetic code of each amino acid (there are 19 instead of 20 letters because two amino acids, leucine and isoleucine, have the same mass and must be treated as a group) and N represents the length of the peptide.
  • the number of terms in the expansion represents the number of composition classes, and the value of each term divided by the sum of the values of all of the terms gives the frequency of any given class. It should be clear to the reader that for all but very small values of N, the frequency of any given class will be very low.
  • the operation of the invention depends upon the presence of a specially engineered DNA sequence adjacent to the unknown DNA.
  • the engineered sequence contains at minimum the following elements: (1) a promoter sequence oriented to promote transcription into the unknown sequence, and (2) a translation initiation sequence, and
  • a coding sequence comprises at minimum a start codon. Transcription from the promoter, followed by translation of the transcript beginning at the start codon, yields a fusion peptide with an N-terminal portion of known amino acid composition followed by a portion of unknown sequence encoded by the unknown DNA. A second known sequence may, in some embodiments, be incorporated into the C-terminal portion of the fusion peptide. Analysis of fusion peptides
  • a fusion peptide Once a fusion peptide has been produced as described above, it must be analyzed to determine its mass and/or its composition and/or its amino acid sequence.
  • Mass Spectrometry is one preferred analytical method because it is fast and highly accurate. A number of specific examples of the application of mass spectrometric analysis to fusion peptides are given later in this specification.
  • the data are compared with the data set generated in silico that contains all possible fusion peptides generated by fusing the known sequence to the reference sequence at all possible positions in the reference sequence and calculating the masses and/or compositions and/or amino acid sequences of the resulting peptides.
  • IMAC insulin-binding protein
  • GST glutathione-S-transferase
  • MBP maltose binding protein
  • GST glutathione-S-transferase
  • MBP maltose binding protein
  • Many means for separating and/or purifying peptides or proteins are also well known and may be applied in certain embodiments of the invention.
  • Certain embodiments of the invention can be used to detect and characterize naturally occurring mutations and DNA polymorphisms, including single nucleotide polymorphisms (SNPs) . This is done by comparing the coding capacity of subsets of the reference sequence with the coding capacity of equivalent subsets of the sequence derived from it by specific nucleotide changes, as follows.
  • SNPs single nucleotide polymorphisms
  • coding capacity is meant the set of the amino acids encoded in at least one reading frame of a sequence; a change in the coding capacity would be due, at minimum, to a change in amino acid composition of at least one encoded peptide.
  • an additional related set of peptides is generated by generating, also in silico, a set of transformed DNA sequences derived from the same portion of the reference DNA sequence, each member of the set containing a different sequence alteration. Each member of the transformed set is then translated in silico to give a transformed set of peptide sequences.
  • the expanded set of peptides will contain 3N members, where N is the length of the relevant portion of the reference nucleotide sequence. (In most cases, some of the members of the new set will be identical due to the degeneracy of the genetic code.)
  • N is the length of the relevant portion of the reference nucleotide sequence.
  • mutations or DNA polymorphisms are detected and quantified, by first producing a PCR amplicon representing a distinct portion of the reference sequence, such as a single exon in a gene of interest.
  • the amplicon is expressed as part of a fusion peptide as described previously.
  • the exon is expressed in frame with respect to the translation initiation codon in the vector, with the result that the peptide comprises the entire amino acid sequence encoded in the exon.
  • the PCR template contains a point mutation that alters the amino acid sequence, this will be observed as, for example, a distinct change in the mass of the peptide relative to the mass of the peptide from the non-mutant exon.
  • a large number of diseases are known to be caused by mutations in known genes, and the mutations in these genes that are responsible for dominant or recessive genetic disease may be examined using the instant invention. These include: Ataxia talangietasia (ATM),
  • Familian adematous polypsosis APC
  • Hereditary breast/ovarian cancer BRCA1, BRCA2
  • Hereditary melanoma CDK2, CDKN2
  • the EMBL3 clone HG3 contains a 10942 base pair insert containing the human nucleolin gene as well as surrounding intergenic sequences (Srivistava, Genbank accession number gb J05584) .
  • Purified HG3 DNA is digested to completion with the restriction endonuclease EcoRI and a plasmid mini-library is constructed by cloning the fragments into the EcoRI site of the vector pUC19 using standard methods.
  • the library is transformed into competent E. coli BLR cells. Ampicillin resistant colonies are selected on LB ampicillin plates, and a single colony is picked and used to prepare a plasmid miniprep .
  • a 250 ml liquid culture of cells from this colony is grown in LB-ampicillin medium at 25 degrees to a density of 2 x 108 cells per ml, induced with 1 mM IPTG for 2 hours, concentrated to a volume of 10 ml by centrifugation, and lysed by sonication in the presence of the protease inhibitors AEBSF, bestatin, E-64 and pepstatin A.
  • a second 250 ml control culture with nonrecombinant pUC19 vector is prepared in parallel. All of the above steps follow standard methods well known in the art.
  • a 10 ul aliquot of each cell lysate is subjected to capillary liquid chromatography (LC) followed by electrospray ionization mass spectrometry (ESI/MS) using methods and procedures well known in the art .
  • LC capillary liquid chromatography
  • ESI/MS electrospray ionization mass spectrometry
  • the spectrum of the lysate from the induced cells is observed to contain a distinct peak, at a position corresponding to a mass of 5253_ 2_Daltons that is not observed in the control cell lysate.
  • the J05584 sequence is scanned to identify each EcoRI site. Five such sites are identified. Each EcoRI fragment is ligated, in silico, to the EcoRI site in the pUC19 vector, producing 10 possible recombinant plasmids, one for each of the two possible orientations of each insert in the vector.
  • the predicted amino acid sequence and molecular mass of each IPTG- inducible hybrid translat ion product ( translated from the mRNA transcribed from the lac promoter in the vector) is calculated , and the masses of the ten possible polypept ides are tabulated , as shown in the table below . Position of EcoRI site Orientation in pUC19 Predicted Peptide Mass
  • the starting material was a cloned gene. If one begins instead with a cloned a cDNA library and uses identical procedures in an iterative manner, the identity of multiple members of the library are ascertained.
  • Example 2 Identification of a subcloned EcoRI fragment of a cloned human gene using peptide affinity capture.
  • the peptide TMITPSLHACRSTLED representing the N-terminal 16 amino acids of the alpha-complementing factor of beta-galactosidase encoded in pUC19 (and also representing the 16 constant N-terminal amino acids in all of the peptides described in Example 1 above) is used to raise a polyclonal rabbit antibody using standard procedures .
  • Example 2 A single ampicillin resistant E. coli colony derived from the mini -library transformation described in Example 1 is picked and induced lysates are prepared as described in Example 1.
  • a control lysate from cells with nonrecombinant vector is prepared in parallel .
  • Immunoreactive proteins are precipitated from the lysates by incubation of 1 ml aliquots with a 1:100 dilution of antiserum followed by precipitation with Protein-A using standard methods.
  • the immunoprecipitate is suspended in 50 ul H20, and a 10 ul aliquot is suspended in 40 ul of MALDI-matrix (_-cyano-4-hydroxycinnamic acid dissolved in 1:2 acetonitrile : 1.5% trifluoroacetic acid (ACCA) , and 100 nL applied to the MS probe, air dried, and subjected to matrix assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry using methods and procedures well known in the art.
  • MALDI-matrix _-cyano-4-hydroxycinnamic acid dissolved in 1:2 acetonitrile : 1.5% trifluoroacetic acid (ACCA)
  • ACCA trifluoroacetic acid
  • the mass spectrum of the immunoprecipitate from the induced cell lysate of the clone under examination is observed to contain a distinct peak, at a position corresponding to a mass of 8485_3 Daltons, that is not observed in the control .
  • Comparison of the experimental results with the values in the table in example 1 above indicates that the insert begins at position 9241 of the reference sequence and proceeds from left to right in the Genbank sequence .
  • Retrieval of the reference sequence beginning at position 9241 indicates that the cloned sequence begins with "GAATTCACATAAATCGCAAATTTTTTTTTCCTTCCC AGAGCCATCCAAAACTCTGTTTGTCAAAGGCCTGTCTGAGGATACCACTGAAGAGAC ATTAAAG" (first 100 nucleotides shown). The identification is confirmed by dideoxy sequencing as described in Example 1.
  • Example 3 Identification of a subcloned EcoRI fragment of a cloned human gene: analysis of peptides from multiple reading frames .
  • the vector pTriplEx is digested with the restriction endonuclease Bglll and the ends of the linearized plasmid are backfilled using Klenow fragment of E. coli DNA polymerase I.
  • the plasmid is treated with the restriction endonuclease Smal , blunt end ligated with DNA ligase and transformed into competent E. coli BLR cells. Ampicillin resistant colonies are selected on LB ampicillin plates, and a single colony is picked and used to prepare a plasmid miniprep.
  • the plasmid here named pTriplEx'
  • pTriplEx' is linearized with EcoRI and a mini library is prepared using as inserts the set of fragments produced by complete digestion of the insert in EMBL3 human nucleolin clone described in example 1.
  • Competent E coli TOPP-1 cells are transformed with the mini library and a single ampicillin resistant colony is isolated.
  • a 250 ml liquid culture of cells from this colony is grown in LB-ampicillin medium at 25 degrees to a density of 2 x 108 cells per ml, induced with 1 mM IPTG for 2 hours, concentrated to a volume of 10 ml by centrifugation, and lysed by sonication on ice with six intermittent 30 second sonication pulses.
  • Control_cells with nonrecombinant plasmid are prepared in parallel . Immunoprecipitates of both lysates are prepared as in Example 2.
  • each EcoRI site in the J05584 sequence is identified and ligated, in silico, to the EcoRI site in the pTriplEx' vector.
  • amino acid sequences of the two expected hybrid translation products are calculated.
  • the mass of each peptide is calculated and all 10 peptide pairs are tabulated, as shown in the table below. Comparison of the experimental results (i.e., peptides of 4255 and 2635 Da.) with the values predicted in the table indicates that the insert begins at position 4028 of the reference sequence and proceeds in the forward direction.
  • Example 4 Identification of a specific mutation in a human gene .
  • Two 20 -nucleotide PCR primers - one representing nucleotides 3190-3210 of the nucleolin sequence described previously (the forward primer) and the other representing the reverse complement of nucleotides 4008-4028 (the reverse primer) - are used to generate an 838 nucleotide PCR amplicon using high fidelity thermostabile proofreading DNA polymerase.
  • the amplicon is cloned into the pTriplEx' vector described previously, and 1000 transformant colonies from each amplification are pooled to create five bacterial cultures, two derived from the parents and three derived from their offspring.
  • Each bacterial culture is treated as described in the previous example to produce five lysates and five MALDI-TOF mass spectra.
  • the spectrum from the father shows two prominent peaks at positions corresponding to 6137 and 5707 Daltons. The same peaks are observed for the peptides derived from two of the offspring.
  • the mother and the third child show not two peaks but three, two at 6137 and 5707 Da and a new one at 6169 Da.
  • the new peak is 32 Da bigger than the 6137 peak, consistent with a change from valine to methionine with respect to the reference sequence.
  • Example 5 Identification of a specific mutations in a human gene; analysis of pooled samples.
  • reference sequence In this example known portions of the reference sequence are used to design PCR primers, which are then used to generate PCR products that are cloned, expressed in fusion peptides, and analyzed in a parallel fashion.
  • the reference sequence predicts a peptide of a particular mass and composition; deviations from the prediction indicate differences in sequence from the reference sequence, in this example single nucleotide polymorphisms.
  • Two oligonucleotide primers are synthesized using standard methods.
  • CCCGAATTCAGCAGGTAAAAATCAAGG the first ten nucleotides contain an EcoRI site (underlined) and last seventeen nucleotides correspond to the first seventeen nucleotides of exon 2 of the human nucleolin gene.
  • GGGGAATTCTTACTCTTCTCCACTGCTAT the last seventeen nucleotides correspond to the reverse complement of the last seventeen nucleotides of exon 2, followed immediately (in the sense orientation of the oligonucleotide) by the stop codon TAA and a sequence that includes an EcoRI site (underlined) .
  • Blood is drawn from twenty individuals and PCR amplicons are produced as described in the previous example, using the two primers just described.
  • the amplicons are pooled and cloned into the EcoRI site of pUC19 as described in Example 2 above, and the bacterial cultures are treated as described in Example 2 above to produce a single MALDI-TOF mass spectrum derived from all twenty pooled samples.
  • the spectrum shows a major peak at 6873_3 Da. , corresponding the predicted mass of the fusion peptide encoded by the exon 2 reference sequence fused to the vector peptide sequence, and two smaller peaks at 6862_3 Da. and 6915_3 Da.
  • the amplitude of the 6862 peak is approximately 1/20 of the 6872 peak, and the amplitude of the 6916 peak is approximately 1/40 that of the 6872 peak.
  • the -10 Da. shift in the 6862 peak relative to the 6872 peak is that predicted for a single nucleotide polymorphism (SNP) that produces a proline to serine substitution in exon 2 that is already known to exist in the human population at a frequency of approximately 5%, and so it is concluded that in the forty haploid genomes present in the twenty individuals, two copies of this polymorphism are very likely present.
  • the +44 Da shift in the 6916 peak indicates an alanine to aspartic acid substitution in exon 2 that was not previously known, and that is present in one copy in the sample of forty haploid genomes .
  • the sample was heterogeneous because amplicons from a number of individual individuals were pooled prior to analysis. But the heterogeneity could, in other cases, be intrinsic to a single sample.
  • the sample could be a tumor biopsy containing, for example, a mixture of cells that are heterogeneous with respect to mutations in oncogenes or tumor suppressor genes, and so PCR amplification of the oncogene or tumor suppressor gene would yield a heterogeneous amplicon.
  • Example 7 Application of a computer program to generate a data set of mass shifts for all possible single nucleotide substitutions in a nucleotide sequence.
  • a computer program was written to compute the mass shifts for all single nucleotide substitutions in a nucleotide sequence.
  • the program uses the amino acid mass values given in the table below.
  • the input to the program is (1) a nucleotide sequence, and (2) a choice by the user of which of the six possible reading frames (3 forward and 3 reverse) to be considered.
  • the program translates the input sequence and computes the masses of the encoded peptides. It then generates all possible single nucleotide substitutions of the sequence, computes a new set of peptides, compares them to the original peptide(s), and lists all of the mass differences between the mutant and non-mutant peptides.
  • the program output is a listing of the peptide mass changes for all possible single nucleotide substitutions in the input sequence.
  • the program then accepts input representing the mass-shift threshold for detection, i.e., the mass shift below which the shift is treated as not detectable.
  • Output is a listing of all mutations in the sequence that are not detectable at the set threshold.
  • the program was run with the 24 nucleotide input sequence CAACTAGAAGAGGTAAGAAACTAT . Two reading frames were selected; the forward reading frame beginning with the first nucleotide (FI) and the reverse (antisense) reading frame beginning with the second antisense nucleotide (R2) .
  • the numbers in the first column denote each nucleotide in the sequence. Note that for each nucleotide in the input sequence there are three possible substitutions, so that the number of lines in the output data set is 72 (3 x 24) .
  • the amino acids encoded in each FI codon are shown in the second column, followed by all possible single nucleotide substitutions at each position in the fourth column.
  • the fifth column shows the amino acids encoded by the new codons
  • the sixth column shows the mass change (if any) due to the amino acid substitution (if any) or translation termination (if any) due to the nucleotide substitution.
  • the last column shows the mass changes due to the same substitutions when translation is in the R2 reading frame.
  • the detection threshold value of 0.8 Daltons was entered; the program output indicated that only one substitution, at position 1 in the encoded peptide, would go undetected at this threshold value.
  • polypeptides from two reading frames makes the analysis significantly more robust than if just one reading frame is used. For example, if just reading frame 1 is used, a shift of -14.03 Daltons could be due to an E-to-D substitution at amino acid 3, or to an E-to-D substitution at amino acid 4, or to an L-to-V substitution at amino acid 2.
  • the additional reading frame data are considered, however, each of these possibilities is distinguished from the others and the ambiguity is thereby eliminated. Indeed, when up to six reading frames are considered, there is little or no ambiguity for the great majority of substitutions, even for sequences as long as several hundred nucleotides.
  • a data set/database such as that generated above can have great utility in the practice of the instant invention when searched by a computer program that searches the database using experimentally determined peptide mass data. Many such programs can be generated.
  • One example is given below. Enter reference sequence
  • Example 8 Analysis of exon 2 of the human rds/peripherin gene.
  • exon 2 of the human rds/peripherin gene (Genbank accession M73531) is shown below. Intron sequence is shown in lower case; exon sequence in upper case .
  • Two primers of sequences GGCCCGGAATTCTCCAGCTGTCTGTTTCCCTTTAAG and AATTTACTCGAGCTACCCCCAGCTGCCCAGGGCCTAC were synthesized and used to PCR amplify rds/peripherin exon 2 from an individual known to carry a wild type allele of rds/peripherin.
  • the amplicon was cut with EcoRI and Xhol and cloned into the EcoRI/XhoI sites of the pGEX derivative described in Nelson et al .
  • the resulting plasmid was cut with Xho 1, treated with Klenow fragment of DNA polymerase, and self-ligated to produce a construct expected to produce a fusion protein with the sequence shown below.
  • the measured masses of the two fusion proteins are 35571 Da and 35630. Da. The difference between the two is 59 Da, indicative of a substitution of arginine for proline in the peptide.
  • Examination of the exon 2 sequence reveals a Fin I site (GTCCC) whose last two nucleotides are part of the first proline codon (CCT) in the sequence. It is concluded that a proline-to-arginine substitution is present at this proline. It is further concluded that the codon very likely suffered a transversion at the second position to create the arginine codon CGG. Dideoxy sequencing across the exon 2 sequence in both constructs confirms these conclusions.
  • Example 9 In vitro analysis of exon 2 of human rds/peripherin .
  • the amplicons described in the previous example are reamplified using the upstream primer 5 ' GGATCCTAATACGACTCACTATAGGGAGACCACCATGCATCACCATCATCACCAT CACCACTCTCCAGCTGTCTGTTTCCCTTTAAG and the downstream primer 5' CTTAGTCATTATACCCCCAGCTGCCCAGGGCCTAC.
  • the upstream primer contains a T7 promoter followed by a translation initiation sequence (start codon underlined) followed by a sequence encoding eight histidines followed by sequence identical to the red/peripherin sequence immediately 5' to rds/peripherin exon 2.
  • the downstream primer contains two stop codons (in antisense orientation) preceding the sequence complimentary to the sequence just 3' to red/peripherin exon 2.
  • the reamplification products are transcribed and translated in a coupled cell free system (transcription by T7 polymerase; translation by rabbit reticulocyte lysate) using established methods and procedures.
  • Immobilized metal affinity chromatography is used to purify the translation products, and the translation products are analyzed by MALDI-TOF mass spectroscopy as in the previous example.
  • the two major translation products are observed to differ by 59.1 Da, indicative of a substitution of arginine for proline in the polypeptide.
  • polypeptide mass the only physical parameter whose value was measured was polypeptide mass. It should be clear to the reader, however, that assessing certain other polypeptide properties, such as amino acid composition or amino acid sequence, may also serve to locate an unknown sequence with respect to the reference sequence. Such data might be obtained, for example, by partial or complete digestion of the peptide, prior to spectrometry, with endopeptidases such as trypsin, chymotrypsin, or pepsin, or with aminopeptidases or carboxypeptidases .
  • Analysis can be performed with a variety of spectrometric methods besides MALDI-TOF and ESI, such as tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , or Fourier transform ion cyclotron resonance (FTICR) mass spectrometry.
  • MS/MS tandem mass spectrometry
  • Q-TOF quadripole time of flight spectrometry
  • FTICR Fourier transform ion cyclotron resonance
  • Other analytical methods well known in the art can also be used to analyze the fusion peptides, such as gel or capillary electrophoresis or high performance liquid chromatography (HPLC) . It should also be clear that the instant invention has utility even if it does not unambiguously assign an unknown sequence to just one place in the reference sequence.
  • a search might eliminate all but four positions in the reference sequence, each on a different chromosome; if the chromosomal location of the unknown sequence were known from some independent determination, such as fluorescence in situ hybridization (FISH), then the assignment could be made unambiguous.
  • FISH fluorescence in situ hybridization
  • the reference sequence is complex, representing, for example, an annotated combination of sequences derived from more than one individual, strain or species, which could be viral, procaryotic or eucaryotic.
  • the instant invention could be used, in medical, forensic or population biology contexts for example, to determine the individual, strain, or species from which the unknown DNA originated, or, conversely, it could be used to rule out an individual, strain or species as the source of origin of the unknown DNA.
  • Some embodiments of the invention include multiplex or pooled-sample analysis wherein peptides encoded in more than one DNA fragment are co-analyzed. For example, peptides encoded in more than one exon of a gene may be combined and analyzed in concert, or samples from multiple individuals may be pooled and analyzed together. Some embodiments of the invention include methods for determining the sequence of a polynucleotide, comprising providing a nucleic acid fragment having homology to a known reference sequence; expressing at least one polypeptide from said fragment; and assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in said known reference sequence.
  • the method also includes wherein said nucleic acid fragment contains a difference with respect to the reference sequence wherein said difference is selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution.
  • said nucleic acid fragment comprises an exon or a cDNA.
  • the polypeptide (s) contain heterologous epitope tags and expressed in living cells or expressed in a cell free systems such as an E.
  • the invention further includes embodiments wherein the peptides are purified by a variety of methods including gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography
  • LC liquid chromatography
  • HPLC differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S-transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaffinity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation.
  • BIOS biomolecular interaction analysis
  • the method further includes embodiments wherein the physical property that is determined is mass, and wherein mass is determined by a variety of methods including mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) ) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography (HPLC) .
  • the method further includes embodiments wherein the physical property that is assessed is partial or complete amino acid composition or sequence.
  • the present invention includes a method for genetic analysis comprising providing a nucleic acid fragment, expressing at least one polypeptide from the fragment, and assessing at least one physical property of said at least one polypeptide to determine the coding capacity of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence.
  • the invention includes method for analyzing fragments that contain a differences with respect to the reference sequence that include of single nucleotide polymorphisms, single nucleotide substitutions, single nucleotide deletions, single nucleotide insertions, multiple nucleotide substitutions, multiple nucleotide deletions, multiple nucleotide insertions, DNA duplications, DNA inversions, DNA translocations, and DNA deletion/substitutions.
  • the invention includes methods for analyzing nucleic acid fragment representing exons or cDNAs , for examining polypeptides that carry epitope tags, for examining polypeptides expressed in living cells or in cell free systems such E.
  • the invention further includes embodiments wherein the peptides are purified by a variety of methods including gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography (HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S-transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaf f inity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes,
  • LC liquid chromatography
  • HPLC high performance liquid chromatography
  • the method further includes embodiments wherein the physical property that is determined is mass, and wherein mass is determined by a variety of methods including mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) ) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography
  • mass spectrometry MALDI-TOF mass spectrometry
  • ESI electrospray ionization mass spectrometry
  • MS/MS tandem mass spectrometry
  • Q-TOF quadripole time of flight spectrometry
  • FTICR Fourier transform ion cyclotron resonance
  • the method further includes embodiments wherein the physical property that is assessed is partial or complete amino acid composition or sequence.
  • the invention includes methods for assessing a disease, condition, genotype, or phenotype comprising providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from said fragment, and assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence, and correlating said determined sequence with said disease, condition, genotype or phenotype.
  • the biological sample may be obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant.
  • kits for treating diseases, conditions, genotypes, or phenotypes comprising providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from the fragment, and assessing at least one physical property of one or more of the polypeptides to determine the sequence of the fragment by comparing the property or properties to the predicted properties of polypeptides encoded in a known reference sequence.
  • the sample may be obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant.
  • the test may detect heterozygote status, and it may indicate responses to drug or therapeutic treatments.
  • the test may be for a genetic disease such as
  • Alzheimer's disease Ataxia talangietasia (ATM), Familial adematous polyposis (APC) , Hereditary breast/ovarian cancer
  • BRCA1, BRCA2 Hereditary melanoma (CDK2, CDKN2), Hereditary non-polypsosis colon cancer (hMSH2 , hMLHl , hPMSl, hPMS2) , Hereditary retinoblastoma (RBI) , Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53), Multiple endocrine neoplasia (MEN1, MEN2) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen receptor deficiency, Tetrahydrobiopterin deficiency, X-Linked aga maglobulinemia, Cystic Fibrosis (CFTR) , Diabetes, Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency, Glucose-6-Phosp
  • Further embodiments include methods for assessing a disease, condition, genotype, or phenotype providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from the fragment, assessing at least one physical property of one or more of the polypeptides to determine the coding capacity of the nucleic acid fragment by comparing said at least one property of the polypeptide (s) to the predicted properties of polypeptides encoded in a known reference sequence, and correlating said determined sequence with said disease, condition, genotype or phenotype.
  • the biological sample may obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant.
  • the particular original source may be blood, sweat, tears, urine, semen, saliva, sweat, feces, skin or hair, or it may come from the environment that the living inhabits or has inhabited, such as air, soil or water.
  • Further embodiments include diagnostic or prognostic tests for a disease, condition, genotype, or phenotype selecting a nucleic acid fragment taken from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant, expressing at least one polypeptide from the fragment, assessing at least one physical property of the polypeptide (s) to determine the coding capacity of the fragment by comparing the property or properties to the predicted properties of polypeptides encoded in a known reference sequence.
  • the particular original source of the nucleic acid may be blood, sweat, tears, urine, semen, saliva, sweat, feces, skin or hair, or it may come from the environment that the living inhabits or has inhabited, such as air, soil or water.
  • the test may detect heterozygote status or indicate or response to a therapeutic drug or treatment.
  • ATM Ataxia talangietasia
  • ATM Familial adematous polyposis
  • APC Familial adematous polyposis
  • BRCA1, BRCA2 Hereditary breast/ovarian cancer
  • BRCA1, BRCA2 Hereditary melanoma
  • CDK2, CDKN2 Hereditary non-polypsosis colon cancer
  • RKI Hereditary retinoblastoma
  • WT1 Hereditary Wilm' s Tumor
  • WT1 Li-Fraumeni syndrome
  • MEN1, MEN2 Multiple endocrine neoplasia
  • VHL Von Hippel-Lindau syndrome
  • VHL Congenital adrenal hyperplasia
  • Androgen receptor deficiency Tetrahydrobiopterin deficiency
  • X-Linked agammaglobulinemia Cystic Fibrosis (CFTR)
  • Diabetes
  • the invention further includes various polypeptides that are created in the embodiments described above .
  • Additional embodiments include computer data structures, comprising: data storage media; and data sets in computer readable form on the data storage media representing a plurality of polypeptide fragments of polypeptides encoded by a reference polynucleotide sequence; and second data sets in computer readable form on the data storage media representing physical properties of each of the polypeptide fragments; and means for correlating empirically derived physical properties of test polypeptides with second data sets to determine the identity of the test polypeptides.
  • the data structures may further comprising third data sets in computer readable form on said data storage media representing polynucleotide fragments encoding the polypeptide fragments; and means for correlating the identity of the test polypeptides with polynucleotide fragments represented in the third data sets.
  • the physical properties may include mass or partial or complete amino acid composition or sequence.
  • the invention includes data structures in which reference polynucleotides have a reading frame, and wherein one data set represents polypeptide fragments encoded in frame and polypeptide fragments encoded out of frame with respect to said reference polynucleotide.
  • Further embodiments include computer implemented methods for ascertaining the identity of nucleic acid fragments encoding polypeptides, wherein the nucleic acid fragments are fragments of known reference sequences, comprising the steps of measuring a physical property of a polypeptide comparing, in a computer, the measured physical property with a data set representing the predicted corresponding physical properties of possible polypeptides that are encoded by fragments of the reference sequence within a predetermined size range; and identifying a match between the measured physical property and a predicted physical property in the data set; and displaying or recording the results of the identifying step.
  • the data set may includes physical properties of polypeptides encoded by in-frame and any of six out-of-frame fragments of said reference polynucleotide.
  • Additional embodiments of the invention include relational data sets useful for detecting and analyzing DNA mutations and polymorphisms comprising a plurality of DNA sequence fragments contained within a reference DNA sequence, the sequences of the polypeptides encoded in said DNA sequence fragments, and the predicted sequences of a plurality of polypeptides encoded in a set of transformed DNA sequence fragments, each member of said set comprised of a DNA sequence related to said DNA sequence fragment by a specific change selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution. Further embodiments include computer programs that search of these data sets .
  • the computer-implemented methods of the present invention can be carried out on a general purpose computer, such as, for example, a PC running the Windows, NT, Unix, or Linux operating systems, or a Macintosh personal computer.
  • a general purpose computer such as, for example, a PC running the Windows, NT, Unix, or Linux operating systems, or a Macintosh personal computer.
  • a more powerful computer mainframe would be desirable.
  • Suitable computers typically have a central processor, computer memory (such as RAM) , and a storage medium, such as a floppy disk, a fixed disk or hard drive, a tape drive, an optical storage medium such as a CD, DVD, or WORM drive, a removable disk, or the like, which can store data in computer-readable form.
  • Such computers typically have a means, such as a monitor, for displaying data or information, and are capable of storing program-generated data in RAM or in the storage medium.
  • Such computers can also advantageously be connected to a printer, for providing a fixed record of information generated by the program.
  • a general purpose computer utilized in the present invention could be programmed with a specific program of the type described herein.
  • this program would generate data sets of all possible nucleotide fragments, in all possible frames and in both orientations. It would predict and store data sets reflecting the translation products of those fragments. It would also store, in a correlatable manner, a data set reflecting a physical property (such as molecular weight) of each of those fragments.
  • One program that could be used in the present invention would compare an empirically determined physical property of a polypeptide translated from a polynucleotide fragment from a biological sample with the data set to determine, for example, which possible polypeptide fragment or which possible polynucleotide fragment corresponds to the sample. In this manner, the identity of DNA in the sample can be determined.
  • information directly or indirectly related to the identity of the polynucleotide fragment from the sample can be displayed, printed, and/or stored. This can include the exact identity or sequence of the polynucleotide, or a tag, label, or name associated therewith. It could also be a diagnosis of a disease, condition, genotype, or phenotype associated with that particular polynucleotide.
  • the invention specified here provides a novel method for analyzing cloned DNA segments and for identifying and/or assaying known or new polymorphisms or mutations in those DNA segments.
  • the ' method has unique and highly useful advantages over all other methods the prior art .
  • multiple promoters and translation start sites can be placed in the known sequence, on one or both sides thereof, so that the unknown sequence is translated in up to six different reading frames.
  • the unknown sequence can be a PCR amplicon that is cloned into a vector in both orientations, thereby yielding a mixture of clones, some translated from one strand and some from the other.
  • promoters and translation start signals can be incorporated near one or both ends of a transposable element, such as Tn3 , Tn5 , Tn7 , TnlO, Ty, P-element, and Mariner; of a virus such as herpes virus, adenovirus, adeno-associated virus; or of a retrovirus .
  • Fusion protein expression need not take place in bacteria, as in the examples given here, but may take place in eucaryotic cells such as yeast or mammalian cells, and cell free expression need not take place in a rabbit reticulocyte lysate, as in the example, but in other cell free systems.
  • peptide capture can be used, such as incorporating biotinylated lysine in the peptides and capturing with avidin or streptavidin.
  • protease recognition sites may be incorporated into the known sequence to aid in fragment preparation, such as placing an enterokinase cleavage site and a poly-histidine sequence upstream of the junction to the unknown sequence so that a peptide for analysis can be released by enterokinase treatment of an affinity captured polypeptide.
  • DNA polymorphisms that are identified and/or detected need not be limited to single nucleotide polymorphisms, as in the examples, but could be of many other kinds such as microsattelite repeats of different lengths or specific single nucleotide deletions, single nucleotide insertions, multiple nucleotide substitutions, multiple nucleotide deletions, multiple nucleotide insertions, DNA duplications, DNA inversions, DNA translocations, DNA deletion/substitutions or other chromosomal rearrangements .

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Biotechnology (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Biophysics (AREA)
  • Analytical Chemistry (AREA)
  • Evolutionary Biology (AREA)
  • Theoretical Computer Science (AREA)
  • Immunology (AREA)
  • Microbiology (AREA)
  • Molecular Biology (AREA)
  • Medical Informatics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Bioinformatics & Computational Biology (AREA)
  • Biochemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Genetics & Genomics (AREA)
  • Peptides Or Proteins (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)

Abstract

A nucleic acid fragment of interest is incorporated into a hybrid artificial gene and expressed in one or more reading frames to produce one or more hybrid polypeptides. The polypeptides are examined with respect to one or more physical parameters, such as mass or amino acid composition. The observed parameter values are used to search a data set of predicted parameter values generated by hypothetical translation of a larger reference nucleic acid sequence so as to determine whether or not the fragment is contained within the reference sequence, and, if it is contained therein, to determine its sequence and/or coding capacity.

Description

METHODS AND PRODUCTS FOR PEPTIDE-BASED DNA SEQUENCE CHARACTERIZATION AND ANALYSIS
FIELD OF INVENTION
This invention relates to the fields of Molecular Biology and Genetics, with particular reference to the identification and analysis of DNA molecules. BACKGROUND
In biology and medicine, there is frequently a need to determine the sequence of a DNA fragment . The fragment may be derived from genomic DNA of viral, procaryotic or eucaryotic origin, or it may be a derived from cDNA. In many cases, the fragment derives from a larger DNA molecule, or set of molecules, whose sequence
(here defined as the reference sequence) is already known. Such cases are not rare and will become increasingly common as more and more natural DNA and cDNA sequences are deposited in available databases.
A number of methods presently exist for determining the nucleotide sequence of a DNA fragment. The most commonly applied method involves cloning the fragment in a plasmid vector of known sequence, purifying the plasmid DNA, annealing a primer complimentary to a portion of the known sequence to one strand of the molecule, extending the primer with DNA polymerase, terminating the polymerization with dideoxy nucleotides, and comparing the lengths of the various terminated molecules to reveal the nucleotide sequence 3' to the primer. Other DNA sequencing methods exist, such as selective cleavage or sequencing by hybridization to biochips . All of these methods are based solely on in vitro DNA chemistry and biochemistry. Other well developed methods, such as SSCP (single strand conformational polymorphism analysis) , heteroduplex sensitivity to nuclease analysis (EMD) , and allele-specific oligonucleotide hybridization, (ASO) exist for detecting mutations or sequence polymorphisms in DNA fragments. These methods, too, are based solely on in vitro DNA chemistry and biochemistry. Rather than examining a DNA molecule by analyzing the DNA itself, in the invention described here the DNA is incorporated into a hybrid artificial gene that is transcribed and translated to produce a hybrid peptide. Physical analysis of the peptide, in conjunction with informatic analysis of the reference sequence, allows one to identify the sequence of the DNA molecule.
The analysis of peptide size as a means to infer information about a gene goes back to at least 1965, when it was reported that phage T4 amber mutants made truncated proteins and that the size of the peptide made in an amber mutant was approximately proportional to the distance of the mutation from the 3' end of the gene. In recent years, this phenomenon has provided the basis for the protein truncation assay for identifying nonsense and frameshift mutations in mammalian genes. In the protein truncation assay, an exon is assayed for chain termination mutations by PCR-amplifying the exon, expressing it in a cell free transcription/translation system, and examining the expressed polypeptide by SDS polyacrylamide gel electrophoresis to determine if it is smaller than a non-mutant control polypeptide. While the protein truncation assay can reveal the presence of a nonsense or frameshift mutation, it is important to note that the assay does not reveal the molecular nature or exact location of the mutation - one does not know if it is a TAG, TGA, TAA or frameshift mutation, and one only knows the approximate location of the mutation within the exon.
There presently exists well developed art by which "unknown" proteins are identified by means of coupled physical and informatic analysis. In these cases, one begins with a naturally occurring protein (or sometimes a fusion protein containing a natural amino sequences) and uses the coupled analysis to determine the protein's identity - for example, by mass spectrometric analysis of tryptic fragment masses followed by search of a database of in silico-generated tryptic fragments, in which the sequences that are the sources of the tryptic fragment data may be taken from existing protein sequence databases or may be created by in silico translation of existing nucleic acid databases. In other cases, mass analysis of peptides derived from known proteins has been used to identify sequence deviations from previously determined .protein sequences .
Whereas the database search activities in the prior art (examples of which are referred to above) are aimed at protein identification and/or analysis, in the instant invention the search activity is aimed at DNA identification or analysis. Thus the two are distinctly different in concept and practice. The artificial hybrid peptides that are analyzed in the instant invention are not naturally occurring, nor are they necessarily biologically active. And yet they have distinct utility as reporters that carry information about the nucleic acids that encode them.
The analysis of peptide reporters provides a number of clear advantages over analysis of the DNA sequences that encode them. One advantage derives from the fact that a peptide is considerably smaller than the DNA that encodes it (individual amino acids averages about 110 Da each whereas the trinucleotides (triplets) that encode them average over N Daltons each) . Another advantage derives from the fact that peptides are much more diverse in composition than nucleic acids, as they are composed of combinations of 20 different amino acids instead of combinations of 4 different nucleotides. Thus, by way of illustration, two random DNA fragments of identical composition (e.g., with 10 adenines, 10 thymines, 15 guanines, and 15 cytosines) are extremely unlikely to encode peptides of identical composition, and so, whereas the two nucleic acids have identical masses and cannot be distinguished on the basis of mass, the peptides that they encode will, except in statistically very rare cases, have different masses and can be readily distinguished on the basis of mass.
SUMMARY OF THE INVENTION
In the invention described here the DNA to be analyzed is incorporated into a hybrid artificial gene that is then transcribed and translated to produce a hybrid peptide. Analysis of the peptide, rather than analysis of the DNA, is used to gain sequence data about the DNA.
Specifically, the mass and/or composition and/or partial or complete amino acid sequence of the hybrid peptide is determined, and the data are used to search for matches in data sets produced by in silico transcription and translation of hybrid artificial genes created in silico using the reference sequence, or using transformations of the reference sequence such as single nucleotide deletions or substitutions thereof. This peptide-based approach to DNA sequence-determination is fundamentally different from all other methods in the art, none of which employs transcription, translation and peptide analysis, as does the instant invention.
It is important to emphasize that the peptides that are produced and analyzed in the course of practicing the invention are not derived from naturally occurring proteins, nor did they exist anywhere prior to their production from the hybrid artificial genes. Likewise the hybrid artificial genes of the invention never existed in nature prior to their production in the course of practicing the invention.
Expected properties of peptides translated from unknown nucleotide sequences
The invention depends on means to translate a portion of the unknown sequence as part of a fusion peptide whose synthesis originates in the known sequence and extends into the unknown sequence that is being characterized. The unknown sequence need not comprise actual protein-coding sequence in the cell from which it originates, although it may in some cases, and so the invention is of general applicability and not confined to coding sequences. The invention also depends on means to accurately measure the mass and/or composition and/or partial or complete amino acid sequence of the fusion peptide. Many methods for making such measurements are known in the art, and a number of them will be discussed later in this specification. But first, let us consider the issue of the expected sizes, masses, and amino acid sequences of the peptides that can be translated from an unknown sequence. For the purpose of this analysis, we will make the simplifying assumption that the unknown sequence is statistically random. Later in this specification, specific examples using natural DNA sequences will be provided. Of the 64 codons, 3 (UAA, UAG, UGA) are nonsense codons that terminate translation. Thus, in any reading frame of a random nucleotide sequence, approximately 1 of 21 codons (-3/64) will be nonsense and approximately 20 of 21 (-61/64) will be sense codons. We now ask the question: if translation begins at an arbitrary nucleotide in a random DNA sequence, how large will the resulting peptide be? The answer can be given in the form of a distribution that can be calculated as follows. The likelihood that the first codon in the sequence is a nonsense codon (and that the peptide will thus be zero amino acids in length) is 1/21, or -4.7%. The likelihood that the first codon is not a nonsense codon and the second codon is a nonsense codon (and that the peptide will thus be one amino acid in length) is 20/21 x 1/21, or -4.5%. The likelihood that the first and second codons are not nonsense codons and the third codon is a nonsense codon
(and that the peptide will thus be two amino acids in length) is 20/21 x 20/21 x 1/21, or -4.3%, and so on. Thus the likelihood that a peptide will have exactly length N is given by the expression (20/21) N x 1/21. Also, since the chance that a peptide will reach at least length N is (20/21) N, we can readily calculate the likelihood of a peptide having a given length or less from the expression
1- (20/2DN.
The table below shows the calculated probabilities, for the first 24 codons of a random DNA sequence, that a given peptide will be of a given length or less. The table indicates that, for example, 0.705
(approximately 70%) of all peptides will be 24 or fewer amino acids in length, and that 0.216 (approximately 20%) of all peptides will be 4 or fewer amino acids in length. In other words, about half of all peptides will be between
5 and 24 amino acids in length.
Per cent of length N Peptide length (N) or less (1- (20/2DN)
0 4.7 1 1 9.3
2 13.6
3 17.7
4 21.6
5 25.4 6 6 28.9
7 32.3
8 35.5
9 38.6
10 41.5 1 111 44.3
12 47.0
13 49.5
14 51.9
15 54.2
1166 56.4
17 58.4
18 60.0
19 62.3
20 64.1
2211 65.8
22 67.4
23 69.0
24 70.5
These expectations were tested by taking the 10,942 base pair sequence that includes the entire human nucleolin gene (Genbank accession number gb J05584) and translating it in silico beginning at number of arbitrarily chosen positions. In particular, translation was begun at every 50th nucleotide beginning at position 2001 and ending at position 4001. The lengths of the encoded peptides, translated from the indicated position to the first in- frame nonsense codon encountered, are listed below. Those between 5 and 24 amino acids are marked with an asterisk. Seventeen out of the 40 peptides are between 4 and 24 amino acids in length, very close to the 20 out of 40 predicted on theoretical grounds, as described above.
Start Peptide length (amino acids)
2001 24* 2051 2 2101 21* 2151 20* 2201 45 2251 2 2301 20* 2351 37 2401 16* 2451 21* 2501 25 2551 30 2601 0 2651 20* 2701 13* 2751 11* 2801 0 2851 4* 2901 21* 2951 16* 3001 14* 3051 0 3101 69 3151 1 3201 26 3251 19* 3301 211 3351 107 3401 86 3451 161 3501 79 3551 36 3601 111 3651 7* 3701 42 3751 61 3801 0 3851 38 3901 11* 3951 40 4001 18*
If the nucleotide sequence is random, the probability that a sequence of a given length translated from it will have a particular amino acid sequence can be calculated simply by multiplying together the frequencies in the genetic code of the codons encoding each amino acid amino acid in the sequence. Since some amino acids have as many as six codons and others as few as one, the predicted frequency will vary depending on the amino acid sequence itself. Thus the sequence LRRLLR, made up entirely of six-codon amino acids, will appear at a frequency of 1 in (6/61)6, or approximately once in one million codons, and the sequence MWWMMW, made up entirely of one-codon amino acids, will appear at a frequency of 1 in (1/61)6, or approximately once in fifty billion codons. The frequencies of other sequences will fall between these two extremes. The important point for us is that even a relatively short sequence will appear very rarely, and so if we can determine the amino acid sequence of a peptide translated from unknown sequence, we can match it to a portion of the reference sequence with high specificity.
Let us now address the issue of the degree of specificity that can be obtained in a search of the reference sequence if we know only the mass, but not the amino acid sequence or composition, of a peptide that is translated from an unknown portion of it? For the sake of this discussion, we will assume that the mass of the peptide is determined with such accuracy as to distinguish each amino acid combination from all others. The number of distinct amino acid combinations and their frequencies is represented by the polynomial expansion (a+b+c+d+ +q+r+s)N, where the letters "a" through "s" (19 letters) represent the frequencies in the genetic code of each amino acid (there are 19 instead of 20 letters because two amino acids, leucine and isoleucine, have the same mass and must be treated as a group) and N represents the length of the peptide. The number of terms in the expansion represents the number of composition classes, and the value of each term divided by the sum of the values of all of the terms gives the frequency of any given class. It should be clear to the reader that for all but very small values of N, the frequency of any given class will be very low.
Depending on the size and sequence of the reference sequence, there may be just one peptide encoded in it of a given mass, or there may be more than one. Generation of fusion peptides
The operation of the invention depends upon the presence of a specially engineered DNA sequence adjacent to the unknown DNA. The engineered sequence contains at minimum the following elements: (1) a promoter sequence oriented to promote transcription into the unknown sequence, and (2) a translation initiation sequence, and
(3) a coding sequence comprises at minimum a start codon. Transcription from the promoter, followed by translation of the transcript beginning at the start codon, yields a fusion peptide with an N-terminal portion of known amino acid composition followed by a portion of unknown sequence encoded by the unknown DNA. A second known sequence may, in some embodiments, be incorporated into the C-terminal portion of the fusion peptide. Analysis of fusion peptides
Once a fusion peptide has been produced as described above, it must be analyzed to determine its mass and/or its composition and/or its amino acid sequence. (Mass Spectrometry is one preferred analytical method because it is fast and highly accurate. A number of specific examples of the application of mass spectrometric analysis to fusion peptides are given later in this specification. The data are compared with the data set generated in silico that contains all possible fusion peptides generated by fusing the known sequence to the reference sequence at all possible positions in the reference sequence and calculating the masses and/or compositions and/or amino acid sequences of the resulting peptides. Absence of a match, which will occur in the great majority of the positions, allows one to exclude that portion of the reference sequence from consideration, whereas a match indicates that it may indeed be the actual sequence coding for the unknown portion of the fusion peptide. If there is only one such match, and if the entire reference sequence has been scanned, then the unknown sequence has been identified. If there are multiple matches, additional data are needed to narrow the conclusion to a single site. Such data can come in a number of forms, including the generation and analysis of more than one fusion peptide from the same region the reference sequence, or the generation and analysis of peptides translated from different reading frames of the same nucleic acid sequence. Specific examples of multiple peptide analysis from nearby, adjacent or overlapping nucleotides are given below and in the claims. But it is important to state that the invention has utility even if it narrows down, but does not absolutely define, the identity of the unknown sequence. Purification of fusion proteins prior to analysis In some cases it may be desirable to purify the fusion peptide prior to analysis. One well established means for doing this is to include a predetermined amino acid sequence (epitope tag) in the known portion of the fusion peptide that binds to a known molecule (e.g., an antibody) or other reagent (immobilized nickel, for example) . The antibody or other reagent is then used to capture and purify the peptide by immunoaffinity chromatography or immobilized metal affinity chromatography
(IMAC) prior to analysis. Or a larger known sequence suitable for affinity purification such as glutathione-S-transferase (GST) , thioredoxin, or maltose binding protein (MBP) , may be incorporated at the N or C- terminus of the peptide. Many means for separating and/or purifying peptides or proteins are also well known and may be applied in certain embodiments of the invention. These include gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography (HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S-transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal -chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaf f inity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation .
Detection and characterization of mutations and DNA polymorphisms
Certain embodiments of the invention can be used to detect and characterize naturally occurring mutations and DNA polymorphisms, including single nucleotide polymorphisms (SNPs) . This is done by comparing the coding capacity of subsets of the reference sequence with the coding capacity of equivalent subsets of the sequence derived from it by specific nucleotide changes, as follows. (By coding capacity is meant the set of the amino acids encoded in at least one reading frame of a sequence; a change in the coding capacity would be due, at minimum, to a change in amino acid composition of at least one encoded peptide.) For every peptide generated in silico by translation of a sequence containing a portion of the reference sequence as described previously in this specification, an additional related set of peptides is generated by generating, also in silico, a set of transformed DNA sequences derived from the same portion of the reference DNA sequence, each member of the set containing a different sequence alteration. Each member of the transformed set is then translated in silico to give a transformed set of peptide sequences. In the case of single nucleotide substitutions, for example, since there are exactly three nucleotide changes that can be made at each position in the relevant portion of the reference DNA sequence, the expanded set of peptides will contain 3N members, where N is the length of the relevant portion of the reference nucleotide sequence. (In most cases, some of the members of the new set will be identical due to the degeneracy of the genetic code.) When the transformed data set is searched with the experimentally determined peptide data, as described previously in this specification, single nucleotide departures from the reference sequence are revealed as matches to members of the transformed data set. In another embodiment of the invention, mutations or DNA polymorphisms are detected and quantified, by first producing a PCR amplicon representing a distinct portion of the reference sequence, such as a single exon in a gene of interest. The amplicon is expressed as part of a fusion peptide as described previously. In one embodiment, the exon is expressed in frame with respect to the translation initiation codon in the vector, with the result that the peptide comprises the entire amino acid sequence encoded in the exon. If the PCR template contains a point mutation that alters the amino acid sequence, this will be observed as, for example, a distinct change in the mass of the peptide relative to the mass of the peptide from the non-mutant exon. A large number of diseases are known to be caused by mutations in known genes, and the mutations in these genes that are responsible for dominant or recessive genetic disease may be examined using the instant invention. These include: Ataxia talangietasia (ATM),
Familian adematous polypsosis (APC) , Hereditary breast/ovarian cancer (BRCA1, BRCA2) , Hereditary melanoma (CDK2, CDKN2) , Hereditary non-polypsosis colon cancer
(hMSH2, hMLHl, hPMSl, hPMS2), Hereditary retinoblastoma
(RBI), Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53) , Multiple endocrine neoplasia (MEN1, MEN2) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen Receptor Mutation, Te t r ahydr ob i op t e r in deficiency, X-Linked agammaglobulinemia, Cystic Fibrosis (CFTR) , Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency, Glucose- 6 -Phosphate deficiency, Pompe Disease, Hemophilia A, Hexosaminidase A deficiency, Human Type I and Type III Collagen deficiency X-linked SCID, Retinitis pigmentosa (RP) LIACAM deficiency, MCAD deficiency, LDL Receptor deficiency, Ornithine Transcarbamylase deficiency, PAX6 Mutation, Phenylketonuria, Tuberous Sclerosis, von Willebrand Factor Disease, Werner Syndrome. DESCRIPTION OF PREFERRED EMBODIMENTS Specific Examples
In examples 1-6 to follow, the masses of the peptides encoded in the various nucleotide sequences were calculated using the table of mass values shown below Peptide masses calculated using these values were rounded off to the nearest Dalton.
Amino Acid Mass
Alanine 71.0 Da
Arginine 156.1 Asparagine 114.0
Aspartic acid 115.0
Cysteine 103.0
Glutamic acid 129.0
Glutamine 128.1 Glycine 57.0
Histidine 137.1
Isoleucine 113.1
Leucine 113.1
Lysine 128.1 Methionine 131.0
Phenylalanine 147.1
Proline 97.1
Serine 87.0
Threonine 101.0 Tryptophan 186.1
Tyrosine 163.1
Valine 99.1 Example 1. Identification of a subcloned EcoRI fragment of a cloned human gene.
The EMBL3 clone HG3 contains a 10942 base pair insert containing the human nucleolin gene as well as surrounding intergenic sequences (Srivistava, Genbank accession number gb J05584) . Purified HG3 DNA is digested to completion with the restriction endonuclease EcoRI and a plasmid mini-library is constructed by cloning the fragments into the EcoRI site of the vector pUC19 using standard methods. The library is transformed into competent E. coli BLR cells. Ampicillin resistant colonies are selected on LB ampicillin plates, and a single colony is picked and used to prepare a plasmid miniprep . A 250 ml liquid culture of cells from this colony is grown in LB-ampicillin medium at 25 degrees to a density of 2 x 108 cells per ml, induced with 1 mM IPTG for 2 hours, concentrated to a volume of 10 ml by centrifugation, and lysed by sonication in the presence of the protease inhibitors AEBSF, bestatin, E-64 and pepstatin A. A second 250 ml control culture with nonrecombinant pUC19 vector is prepared in parallel. All of the above steps follow standard methods well known in the art.
A 10 ul aliquot of each cell lysate is subjected to capillary liquid chromatography (LC) followed by electrospray ionization mass spectrometry (ESI/MS) using methods and procedures well known in the art . The spectrum of the lysate from the induced cells is observed to contain a distinct peak, at a position corresponding to a mass of 5253_ 2_Daltons that is not observed in the control cell lysate.
To identify the nucleotide sequence responsible for the 5253 peak, the J05584 sequence is scanned to identify each EcoRI site. Five such sites are identified. Each EcoRI fragment is ligated, in silico, to the EcoRI site in the pUC19 vector, producing 10 possible recombinant plasmids, one for each of the two possible orientations of each insert in the vector. The predicted amino acid sequence and molecular mass of each IPTG- inducible hybrid translat ion product ( translated from the mRNA transcribed from the lac promoter in the vector) is calculated , and the masses of the ten possible polypept ides are tabulated , as shown in the table below . Position of EcoRI site Orientation in pUC19 Predicted Peptide Mass
3190 forward 7070 Daltons
3190 reverse 5253
4028 forward 3998
4028 reverse 5268
6066 forward 4969
6066 reverse 2726
9241 forward 8485
9241 reverse 3109
9543 forward 2840
9543 reverse 3878
The mass values above were computed by translating each hypothetical fusion polypeptide and removing the N-terminal methionine.
Comparison of the experimental results with the values in the table indicates reveals a match to the predicted mass value for one of the ten candidates specifically the sequence that begins at position 3190 of the reference sequence and proceeds from right to left. Retrieval of the reference sequence beginning at position 3190 indicates that the cloned sequence begins with "GAATTCTTACACCTCATACTTTCCCAAGCCCCAACTTTCTCATCTGAAAATGGTAA TAGTATCATCCTTACATGTTTAAGGTCATGAATTGCTATGTGTA..." (first 100 nucleotides shown) . The identification is confirmed by dideoxy sequencing from a primer 150 nucleotides upstream of the junction between the pUC19 sequence and the EcoRI fragment .
In this example the starting material was a cloned gene. If one begins instead with a cloned a cDNA library and uses identical procedures in an iterative manner, the identity of multiple members of the library are ascertained.
Example 2. Identification of a subcloned EcoRI fragment of a cloned human gene using peptide affinity capture. The peptide TMITPSLHACRSTLED, representing the N-terminal 16 amino acids of the alpha-complementing factor of beta-galactosidase encoded in pUC19 (and also representing the 16 constant N-terminal amino acids in all of the peptides described in Example 1 above) is used to raise a polyclonal rabbit antibody using standard procedures .
A single ampicillin resistant E. coli colony derived from the mini -library transformation described in Example 1 is picked and induced lysates are prepared as described in Example 1. A control lysate from cells with nonrecombinant vector is prepared in parallel . Immunoreactive proteins are precipitated from the lysates by incubation of 1 ml aliquots with a 1:100 dilution of antiserum followed by precipitation with Protein-A using standard methods. The immunoprecipitate is suspended in 50 ul H20, and a 10 ul aliquot is suspended in 40 ul of MALDI-matrix (_-cyano-4-hydroxycinnamic acid dissolved in 1:2 acetonitrile : 1.5% trifluoroacetic acid (ACCA) , and 100 nL applied to the MS probe, air dried, and subjected to matrix assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry using methods and procedures well known in the art.
The mass spectrum of the immunoprecipitate from the induced cell lysate of the clone under examination is observed to contain a distinct peak, at a position corresponding to a mass of 8485_3 Daltons, that is not observed in the control . Comparison of the experimental results with the values in the table in example 1 above indicates that the insert begins at position 9241 of the reference sequence and proceeds from left to right in the Genbank sequence . Retrieval of the reference sequence beginning at position 9241 indicates that the cloned sequence begins with "GAATTCACATAAATCGCAAATTTTTTTTTCCTTCCC AGAGCCATCCAAAACTCTGTTTGTCAAAGGCCTGTCTGAGGATACCACTGAAGAGAC ATTAAAG..." (first 100 nucleotides shown). The identification is confirmed by dideoxy sequencing as described in Example 1.
Example 3. Identification of a subcloned EcoRI fragment of a cloned human gene: analysis of peptides from multiple reading frames .
The vector pTriplEx is digested with the restriction endonuclease Bglll and the ends of the linearized plasmid are backfilled using Klenow fragment of E. coli DNA polymerase I. The plasmid is treated with the restriction endonuclease Smal , blunt end ligated with DNA ligase and transformed into competent E. coli BLR cells. Ampicillin resistant colonies are selected on LB ampicillin plates, and a single colony is picked and used to prepare a plasmid miniprep. The plasmid, here named pTriplEx' , is linearized with EcoRI and a mini library is prepared using as inserts the set of fragments produced by complete digestion of the insert in EMBL3 human nucleolin clone described in example 1. Competent E coli TOPP-1 cells are transformed with the mini library and a single ampicillin resistant colony is isolated. A 250 ml liquid culture of cells from this colony is grown in LB-ampicillin medium at 25 degrees to a density of 2 x 108 cells per ml, induced with 1 mM IPTG for 2 hours, concentrated to a volume of 10 ml by centrifugation, and lysed by sonication on ice with six intermittent 30 second sonication pulses. Control_cells with nonrecombinant plasmid are prepared in parallel . Immunoprecipitates of both lysates are prepared as in Example 2.
An 10 ul aliquot of each immunoprecipitate is suspended in 40 ul of MALDI-matrix and subjected to MALDI-TOF mass spectrometry. The spectrum of the lysate from the plasmid-containing cells is observed to contain two distinct peaks not present in the control lysate, one at a mass of 4254_2 Daltons and the other at a mass of 2635_2 Daltons.
To identify the nucleotide sequence adjacent to the pTriplEx' vector, each EcoRI site in the J05584 sequence is identified and ligated, in silico, to the EcoRI site in the pTriplEx' vector. For each such in silico construct, the amino acid sequences of the two expected hybrid translation products (from each of the start codons in the vector to the first in frame stop codons encountered in the insert) are calculated. The mass of each peptide is calculated and all 10 peptide pairs are tabulated, as shown in the table below. Comparison of the experimental results (i.e., peptides of 4255 and 2635 Da.) with the values predicted in the table indicates that the insert begins at position 4028 of the reference sequence and proceeds in the forward direction. It is concluded that the 5' end of the sequence joined to the vector is "GAATTCTCTTGGGTT GTTGTGGTGTGCTAGACTTAATTACCCATGAATGATTTTGTCCTCTTGAGAAAATTT CAATAGCACATCTATTAGTGTTTTTTAT ... " (first 100 nucleotides shown) . The identification is confirmed by dideoxy sequencing from the plasmid using a primer 150 nucleotides 3' to the pTriplEx' EcoRI site.
Position of Orientation
EcoRI site in pTriplEx' Start Codon Predicted Peptide Mass
3190 forward 1st 6137
3190 forward 2nd 5707
3190 reverse 1st 6278
3190 reverse 2nd 3891
4208 forward 1st 4255
4208 forward 2nd 2635
4208 reverse 1st 19748
4208 reverse 2nd 3905
6066 forward 1st 3595
6066 forward 2nd 3606
6066 reverse 1st 6401
6066 reverse 2nd 1363
9241 forward 1st 3583
9241 forward 2nd 7122
9241 reverse 1st 4582
9241 reverse 2nd 1746
9543 forward 1st 5306
9543 forward 2nd 1477
9543 reverse 1st 9906
9543 reverse 2nd 2516 The mass values above are computed by translating each hypothetical fusion polypeptide without the N-terminal methionine that is removed in vivo in E. coli.
Example 4. Identification of a specific mutation in a human gene .
Blood is drawn from a man and wife and from their three children, and DNA is prepared from blood leukocytes of each using standard methods. Two 20 -nucleotide PCR primers - one representing nucleotides 3190-3210 of the nucleolin sequence described previously (the forward primer) and the other representing the reverse complement of nucleotides 4008-4028 (the reverse primer) - are used to generate an 838 nucleotide PCR amplicon using high fidelity thermostabile proofreading DNA polymerase. The amplicon is cloned into the pTriplEx' vector described previously, and 1000 transformant colonies from each amplification are pooled to create five bacterial cultures, two derived from the parents and three derived from their offspring. Each bacterial culture is treated as described in the previous example to produce five lysates and five MALDI-TOF mass spectra. The spectrum from the father shows two prominent peaks at positions corresponding to 6137 and 5707 Daltons. The same peaks are observed for the peptides derived from two of the offspring. The mother and the third child show not two peaks but three, two at 6137 and 5707 Da and a new one at 6169 Da. The new peak is 32 Da bigger than the 6137 peak, consistent with a change from valine to methionine with respect to the reference sequence. The fact that there is no new peak derived from the 5707 Da peak indicates that the base change (s) responsible for the valine-to-methionine substitution in the larger peptide is silent with respect to the reading frame encoding the 5707 Da. peptide. Of the six valine codons in the 6137 Da. peptide, only one, the GTG codon at position 3223, can be changed to give this result, the change being a G to A transition (to ATG) at position 3223. It is concluded that the mother and third child are heterozygous carriers for a single nucleotide polymorphism, a G to A transition, at position 3223. Dideoxy sequencing across the relevant region confirms this conclusion.
Example 5. Identification of a specific mutations in a human gene; analysis of pooled samples.
In this example known portions of the reference sequence are used to design PCR primers, which are then used to generate PCR products that are cloned, expressed in fusion peptides, and analyzed in a parallel fashion. The reference sequence predicts a peptide of a particular mass and composition; deviations from the prediction indicate differences in sequence from the reference sequence, in this example single nucleotide polymorphisms.
Two oligonucleotide primers are synthesized using standard methods. In one, CCCGAATTCAGCAGGTAAAAATCAAGG, the first ten nucleotides contain an EcoRI site (underlined) and last seventeen nucleotides correspond to the first seventeen nucleotides of exon 2 of the human nucleolin gene. The other, GGGGAATTCTTACTCTTCTCCACTGCTAT, the last seventeen nucleotides correspond to the reverse complement of the last seventeen nucleotides of exon 2, followed immediately (in the sense orientation of the oligonucleotide) by the stop codon TAA and a sequence that includes an EcoRI site (underlined) . Blood is drawn from twenty individuals and PCR amplicons are produced as described in the previous example, using the two primers just described. The amplicons are pooled and cloned into the EcoRI site of pUC19 as described in Example 2 above, and the bacterial cultures are treated as described in Example 2 above to produce a single MALDI-TOF mass spectrum derived from all twenty pooled samples. The spectrum shows a major peak at 6873_3 Da. , corresponding the predicted mass of the fusion peptide encoded by the exon 2 reference sequence fused to the vector peptide sequence, and two smaller peaks at 6862_3 Da. and 6915_3 Da. The amplitude of the 6862 peak is approximately 1/20 of the 6872 peak, and the amplitude of the 6916 peak is approximately 1/40 that of the 6872 peak. The -10 Da. shift in the 6862 peak relative to the 6872 peak is that predicted for a single nucleotide polymorphism (SNP) that produces a proline to serine substitution in exon 2 that is already known to exist in the human population at a frequency of approximately 5%, and so it is concluded that in the forty haploid genomes present in the twenty individuals, two copies of this polymorphism are very likely present. The +44 Da shift in the 6916 peak indicates an alanine to aspartic acid substitution in exon 2 that was not previously known, and that is present in one copy in the sample of forty haploid genomes .
In this example the sample was heterogeneous because amplicons from a number of individual individuals were pooled prior to analysis. But the heterogeneity could, in other cases, be intrinsic to a single sample. For example, the sample could be a tumor biopsy containing, for example, a mixture of cells that are heterogeneous with respect to mutations in oncogenes or tumor suppressor genes, and so PCR amplification of the oncogene or tumor suppressor gene would yield a heterogeneous amplicon.
Example 7. Application of a computer program to generate a data set of mass shifts for all possible single nucleotide substitutions in a nucleotide sequence.
A computer program was written to compute the mass shifts for all single nucleotide substitutions in a nucleotide sequence. The program uses the amino acid mass values given in the table below. The input to the program is (1) a nucleotide sequence, and (2) a choice by the user of which of the six possible reading frames (3 forward and 3 reverse) to be considered. The program translates the input sequence and computes the masses of the encoded peptides. It then generates all possible single nucleotide substitutions of the sequence, computes a new set of peptides, compares them to the original peptide(s), and lists all of the mass differences between the mutant and non-mutant peptides. The program output is a listing of the peptide mass changes for all possible single nucleotide substitutions in the input sequence. The program then accepts input representing the mass-shift threshold for detection, i.e., the mass shift below which the shift is treated as not detectable. Output is a listing of all mutations in the sequence that are not detectable at the set threshold.
Amino Acid Symbol Mass
Alanine A 71. .08 Da
Arginine R 156. .19
Asparagine N 114. .10
Aspartic acid D 115. .09
Cysteine C 103. .14
Glutamic acid E 129. .12
Glutamine Q 128. .13
Glycine G 57. .05
Histidine H 137, .14
Isoleucine I 113. .16
Leucine L 113 , .16
Lysine K 128, .17
Methionine M 131, .19
Phenylalanine F 147 .18
Proline P 97 .12
Serine S 87 .08
Threonine T 101 .10
Tryptophan W 186 .21
Tyrosine Y 163 .18
Valine V 99 .13
Nonsense z
The program was run with the 24 nucleotide input sequence CAACTAGAAGAGGTAAGAAACTAT . Two reading frames were selected; the forward reading frame beginning with the first nucleotide (FI) and the reverse (antisense) reading frame beginning with the second antisense nucleotide (R2) .
The results are shown below.
[begin] Enter Sequence :
[input] CAACTAGAAGAGGTAAGAAACTAT [output] Protein: QLEEVRNY
Which reading frames would you like to examine?
1: Forward (FI)
2 : Forward ; f irst base removed (F2 ) 3: Forward; second base removed (F2) 4: Reverse (Rl)
5: Reverse first base removed (R2) 6: Reverse second removed (R3)
[input] 1,5
[output ] MASS DIFFERENCES Location Mutation Frame FI Frame : R2
None 1032. 13 722. 89
/A(K) 0. 04 0. 00
1 cH G(E) 0. 99 0. 00 \T(Z) -1032. 13 0. 00 /G(R) 28. 06 0. 00
2 (Q) AH T(L) -14. 97 0. 00 \C(P) -31. 01 0. 00 /G(Q) 0. 00 0. 00
3 A-< T(H) 9. 01 0. 00 \C(H) 9. 01 0. 00
/A(I) 0 00 276 34
4 c-{ G(V) -14 03 276 34 \T(L) 0 00 0 00 /C(P) -16 04 299 37
5 (L) T-< A(Q) 14 97 226 32 \G(R) 43 03 200 24 /G(L) 0 00 241 29
6 A- [ T(L) 0 00 241 33 \C(L) 0 00 242 28
/T(Z) -790 84 -34 02
7 G- [ C(Q) -0 99 -34 02 \A(K) -0 95 0 00 /G(G) -72 07 -60 10
8 (E) A- T(V) -29 99 16 .00 \C(A) -58 04 -44 .04 /G(E) 0 .00 -34 .02
9 A- T(D) -14 .03 -34 .02 \C(D) -14 .03 -48 .05
/T(Z) -661 .72 0 .00
10 G- ( C(Q) -0 .99 0 .00 \A(K) -0 .95 0 .00 /G(G) -72 .07 -16 .04
11 (E) A- { T(V) -29 .99 23 .98 \C(A) -58 .04 43 .03 /T(D) -14 .03 0 .00
12 G- [ C(D) -14 .03 -14 .03 \A(E) 0 .00 34 .02
/T(L) 14 .03 -423 .52
13 G- { C(L) 14 .03 -423 .52 \A(I) 14 .03 0 .00 /C(A) -28.05 -60.04
14 (V) T-< A(E) 29.99 -16.00 \G(G) -42.08 -76.10 /G(V) 0.00 -26.04
15 A-< T(V) 0.00 -49.08 \C(V) 0.00 -48.09
Figure imgf000026_0001
/G(D) 0.99 0.00
19 A- [ T(Y) 49.08 0.00 \C(H) 23.04 0.00 /G(S) -27.02 -28.05
20 (N) A- ( T(I) -0.94 15.96 \C(T) -13.00 -42.08 /A(K) 14.07 48.05
21 C- G(K) 14.07 14.03 \T(N) 0.00 14.03
/C(H) -26.04 18.03
\G(D) -49.08 0.00
22 T- { A(N) -48.09 0.00 /G(C) -60.04 -12.06
23 (Y) A- { T(F) -16.00 15.01 \C(S) -76.10 43.03 /C(Y) 0.00 -14.03
24 T- { A(Z) 163.18 0.00 \G(Z) 163.18 0.00
Enter the detection threshold: [input] 0.8 Dalton. [output] Undetectable amino acid substitutions: 1. (Q)C-A(K)
The numbers in the first column denote each nucleotide in the sequence. Note that for each nucleotide in the input sequence there are three possible substitutions, so that the number of lines in the output data set is 72 (3 x 24) . The amino acids encoded in each FI codon are shown in the second column, followed by all possible single nucleotide substitutions at each position in the fourth column. The fifth column shows the amino acids encoded by the new codons, and the sixth column shows the mass change (if any) due to the amino acid substitution (if any) or translation termination (if any) due to the nucleotide substitution. The last column shows the mass changes due to the same substitutions when translation is in the R2 reading frame. The detection threshold value of 0.8 Daltons was entered; the program output indicated that only one substitution, at position 1 in the encoded peptide, would go undetected at this threshold value.
Note also that the expression of polypeptides from two reading frames makes the analysis significantly more robust than if just one reading frame is used. For example, if just reading frame 1 is used, a shift of -14.03 Daltons could be due to an E-to-D substitution at amino acid 3, or to an E-to-D substitution at amino acid 4, or to an L-to-V substitution at amino acid 2. When the additional reading frame data are considered, however, each of these possibilities is distinguished from the others and the ambiguity is thereby eliminated. Indeed, when up to six reading frames are considered, there is little or no ambiguity for the great majority of substitutions, even for sequences as long as several hundred nucleotides.
A data set/database such as that generated above can have great utility in the practice of the instant invention when searched by a computer program that searches the database using experimentally determined peptide mass data. Many such programs can be generated. One example is given below. Enter reference sequence
Compute reverse complement of reference sequence Translate beginning at each nucleotide
Translate beginning at each nucleotide
Create relational database of peptides and nucleotide positions
Compute predicted masses of peptides; create relational database of peptides, masses, and nucleotide positions Enter experimentally determined mass data for peptide (s) derived from unknown sequence
Search database for correspondence between entered mass data and predicted mass values in database
Output location of unknown sequence
Example 8. Analysis of exon 2 of the human rds/peripherin gene.
The sequence of exon 2 of the human rds/peripherin gene (Genbank accession M73531) is shown below. Intron sequence is shown in lower case; exon sequence in upper case . gggaagcccatctccagctgtctgtttccctttaagTCGAATCAAGAGCAACGTGGA TGGGCGGTACCTGGTGGACGGCGTCCCTTTCAGCTGCTGCAATCCTAGCTCGCCACG GCCCTGCATCCAGTATCAGATCACCAACAACTCAGCACACTACAGTTACGACCACCA GACGGAGGAGCTCAACCTGTGGGTGCGTGGCTGCAGGGCTGCCCTGCTGAGCTACTA CAGCAGCCTCATGAACTCCATGGGTGTCGTCACGCTCCTCATTTGGCTCTTCGAGgt aggccctgggcagctgggggtagagggtaaggagagcctcc
Two primers , of sequences GGCCCGGAATTCTCCAGCTGTCTGTTTCCCTTTAAG and AATTTACTCGAGCTACCCCCAGCTGCCCAGGGCCTAC were synthesized and used to PCR amplify rds/peripherin exon 2 from an individual known to carry a wild type allele of rds/peripherin. The amplicon was cut with EcoRI and Xhol and cloned into the EcoRI/XhoI sites of the pGEX derivative described in Nelson et al . The resulting plasmid was cut with Xho 1, treated with Klenow fragment of DNA polymerase, and self-ligated to produce a construct expected to produce a fusion protein with the sequence shown below. MSPI GYWKIKGLVQPTRLLLEYLEEKYEEHLYERDEGDKWRNKKFELGLEFPNLPY YIDGDVKLTQSMAIIRYIADKHNMLGGCPKERAEISMLEGAVLDIRYGVSRIAYSKD FETLKVDFLSKLPEMLKMFEDRLCHKTYLNGDHVTHPDFMLYDALDWLYMDPMCLD AFPKLVCFKKRIEAIPQIDKYLKSSKYIAWPLQGWQATFGGGDHPPKSDLIEGRGIQ DLVPHTTPHHTTPHHTTPHHTTPQDLNSPAVCFPLSRIKSNVDGRYLVDGVPFSCCN PSSPRPCIQYQITNNSAHYSYDHQTEELNLWVRGCRAALLSYYSSLMNSMGWTLLI WLFEVGPGQLGVARSSGRIVTD The same primers were used to amplify rds/peripherin exon 2 from an individual known to carry a mutation in the exon that removes a Finl restriction site. An amplicon containing the mutation was cloned and expressed as described above for the non-mutant sequence. Cells containing both constructs were grown to mid log phase in LB medium, induced with ImM IPTG, and incubated for 2 hours at 25_. Cells were collected by centrifugation and extracted with B-per according to the suppliers instructions. GST fusion proteins were purified by standard methods for analysis by MALDI-TOF mass spectrometry, which is performed as described previously.
The measured masses of the two fusion proteins are 35571 Da and 35630. Da. The difference between the two is 59 Da, indicative of a substitution of arginine for proline in the peptide. Examination of the exon 2 sequence reveals a Fin I site (GTCCC) whose last two nucleotides are part of the first proline codon (CCT) in the sequence. It is concluded that a proline-to-arginine substitution is present at this proline. It is further concluded that the codon very likely suffered a transversion at the second position to create the arginine codon CGG. Dideoxy sequencing across the exon 2 sequence in both constructs confirms these conclusions. Example 9. In vitro analysis of exon 2 of human rds/peripherin .
The amplicons described in the previous example are reamplified using the upstream primer 5 ' GGATCCTAATACGACTCACTATAGGGAGACCACCATGCATCACCATCATCACCAT CACCACTCTCCAGCTGTCTGTTTCCCTTTAAG and the downstream primer 5' CTTAGTCATTATACCCCCAGCTGCCCAGGGCCTAC. The upstream primer contains a T7 promoter followed by a translation initiation sequence (start codon underlined) followed by a sequence encoding eight histidines followed by sequence identical to the red/peripherin sequence immediately 5' to rds/peripherin exon 2. The downstream primer contains two stop codons (in antisense orientation) preceding the sequence complimentary to the sequence just 3' to red/peripherin exon 2.
The reamplification products are transcribed and translated in a coupled cell free system (transcription by T7 polymerase; translation by rabbit reticulocyte lysate) using established methods and procedures. Immobilized metal affinity chromatography is used to purify the translation products, and the translation products are analyzed by MALDI-TOF mass spectroscopy as in the previous example. The two major translation products are observed to differ by 59.1 Da, indicative of a substitution of arginine for proline in the polypeptide. By logic identical to that presented in the previous example, it is concluded that that the polypeptides differ by a proline-to-arginine substitution at the position of the first proline of the exon-encoded sequence.
In the examples given above, the only physical parameter whose value was measured was polypeptide mass. It should be clear to the reader, however, that assessing certain other polypeptide properties, such as amino acid composition or amino acid sequence, may also serve to locate an unknown sequence with respect to the reference sequence. Such data might be obtained, for example, by partial or complete digestion of the peptide, prior to spectrometry, with endopeptidases such as trypsin, chymotrypsin, or pepsin, or with aminopeptidases or carboxypeptidases . Analysis can be performed with a variety of spectrometric methods besides MALDI-TOF and ESI, such as tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , or Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. Other analytical methods well known in the art can also be used to analyze the fusion peptides, such as gel or capillary electrophoresis or high performance liquid chromatography (HPLC) . It should also be clear that the instant invention has utility even if it does not unambiguously assign an unknown sequence to just one place in the reference sequence. For example, a search might eliminate all but four positions in the reference sequence, each on a different chromosome; if the chromosomal location of the unknown sequence were known from some independent determination, such as fluorescence in situ hybridization (FISH), then the assignment could be made unambiguous. Likewise, there may be circumstances where the reference sequence is complex, representing, for example, an annotated combination of sequences derived from more than one individual, strain or species, which could be viral, procaryotic or eucaryotic. In such circumstances, the instant invention could be used, in medical, forensic or population biology contexts for example, to determine the individual, strain, or species from which the unknown DNA originated, or, conversely, it could be used to rule out an individual, strain or species as the source of origin of the unknown DNA.
Some embodiments of the invention include multiplex or pooled-sample analysis wherein peptides encoded in more than one DNA fragment are co-analyzed. For example, peptides encoded in more than one exon of a gene may be combined and analyzed in concert, or samples from multiple individuals may be pooled and analyzed together. Some embodiments of the invention include methods for determining the sequence of a polynucleotide, comprising providing a nucleic acid fragment having homology to a known reference sequence; expressing at least one polypeptide from said fragment; and assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in said known reference sequence. The method also includes wherein said nucleic acid fragment contains a difference with respect to the reference sequence wherein said difference is selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution. The method further includes embodiments wherein said nucleic acid fragment comprises an exon or a cDNA. The method further includes embodiments wherein the polypeptide (s) contain heterologous epitope tags and expressed in living cells or expressed in a cell free systems such as an E. coli extract, rabbit reticulocyte extract, or wheat germ extract. The invention further includes embodiments wherein the peptides are purified by a variety of methods including gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography
(HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S-transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaffinity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation. The method further includes embodiments wherein the physical property that is determined is mass, and wherein mass is determined by a variety of methods including mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) ) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography (HPLC) . The method further includes embodiments wherein the physical property that is assessed is partial or complete amino acid composition or sequence. In another embodiment the present invention includes a method for genetic analysis comprising providing a nucleic acid fragment, expressing at least one polypeptide from the fragment, and assessing at least one physical property of said at least one polypeptide to determine the coding capacity of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence. In a further embodiment the invention includes method for analyzing fragments that contain a differences with respect to the reference sequence that include of single nucleotide polymorphisms, single nucleotide substitutions, single nucleotide deletions, single nucleotide insertions, multiple nucleotide substitutions, multiple nucleotide deletions, multiple nucleotide insertions, DNA duplications, DNA inversions, DNA translocations, and DNA deletion/substitutions. In further embodiments the invention includes methods for analyzing nucleic acid fragment representing exons or cDNAs , for examining polypeptides that carry epitope tags, for examining polypeptides expressed in living cells or in cell free systems such E. coli extracts, rabbit reticulocyte extracts, and wheat germ extracts. The invention further includes embodiments wherein the peptides are purified by a variety of methods including gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography (HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S-transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaf f inity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation. The method further includes embodiments wherein the physical property that is determined is mass, and wherein mass is determined by a variety of methods including mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) ) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography
(HPLC) . The method further includes embodiments wherein the physical property that is assessed is partial or complete amino acid composition or sequence.
In additional embodiments, the invention includes methods for assessing a disease, condition, genotype, or phenotype comprising providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from said fragment, and assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence, and correlating said determined sequence with said disease, condition, genotype or phenotype. The biological sample may be obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant. Other embodiments include diagnostic or prognostic tests for diseases, conditions, genotypes, or phenotypes comprising providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from the fragment, and assessing at least one physical property of one or more of the polypeptides to determine the sequence of the fragment by comparing the property or properties to the predicted properties of polypeptides encoded in a known reference sequence. The sample may be obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant. In further embodiments, the test may detect heterozygote status, and it may indicate responses to drug or therapeutic treatments. The test may be for a genetic disease such as
Alzheimer's disease, Ataxia talangietasia (ATM), Familial adematous polyposis (APC) , Hereditary breast/ovarian cancer
(BRCA1, BRCA2) , Hereditary melanoma (CDK2, CDKN2), Hereditary non-polypsosis colon cancer (hMSH2 , hMLHl , hPMSl, hPMS2) , Hereditary retinoblastoma (RBI) , Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53), Multiple endocrine neoplasia (MEN1, MEN2) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen receptor deficiency, Tetrahydrobiopterin deficiency, X-Linked aga maglobulinemia, Cystic Fibrosis (CFTR) , Diabetes, Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency, Glucose-6-Phosphate deficiency, Pompe Disease, Hemophilia A, Hexosaminidase A deficiency, Human Type I and Type III Collagen deficiency X-linked SCID, Retinitis pigmentosa (RP) LIACAM deficiency, MCAD deficiency, LDL Receptor deficiency, Ornithine Transcarbamylase deficiency, PAX6 Mutation Phenylketonuria, RBI Gene Mutation, Tuberous Sclerosis, von Willebrand Factor Disease, Werner syndrome, cancer, or an infectious disease. Further embodiments include methods for assessing a disease, condition, genotype, or phenotype providing a nucleic acid fragment from a biological sample, and expressing at least one polypeptide from the fragment, assessing at least one physical property of one or more of the polypeptides to determine the coding capacity of the nucleic acid fragment by comparing said at least one property of the polypeptide (s) to the predicted properties of polypeptides encoded in a known reference sequence, and correlating said determined sequence with said disease, condition, genotype or phenotype. The biological sample may obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant. The particular original source may be blood, sweat, tears, urine, semen, saliva, sweat, feces, skin or hair, or it may come from the environment that the living inhabits or has inhabited, such as air, soil or water. Further embodiments include diagnostic or prognostic tests for a disease, condition, genotype, or phenotype selecting a nucleic acid fragment taken from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, or secretion of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant, expressing at least one polypeptide from the fragment, assessing at least one physical property of the polypeptide (s) to determine the coding capacity of the fragment by comparing the property or properties to the predicted properties of polypeptides encoded in a known reference sequence. The particular original source of the nucleic acid may be blood, sweat, tears, urine, semen, saliva, sweat, feces, skin or hair, or it may come from the environment that the living inhabits or has inhabited, such as air, soil or water. The test may detect heterozygote status or indicate or response to a therapeutic drug or treatment. It may detect genetic disease, such Alzheimer's disease, Ataxia talangietasia (ATM) , Familial adematous polyposis (APC), Hereditary breast/ovarian cancer (BRCA1, BRCA2) , Hereditary melanoma (CDK2, CDKN2), Hereditary non-polypsosis colon cancer (hMSH2, hMLHl, hPMSl, hPMS2), Hereditary retinoblastoma (RBI), Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53), Multiple endocrine neoplasia (MEN1, MEN2) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen receptor deficiency, Tetrahydrobiopterin deficiency, X-Linked agammaglobulinemia, Cystic Fibrosis (CFTR) , Diabetes, Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency, Glucose- 6 -Phosphate deficiency, Pompe Disease, Hemophilia A, Hexosaminidase A deficiency, Human Type I and Type III Collagen deficiency X-linked SCID, Retinitis pigmentosa (RP) LIACAM deficiency, MCAD deficiency, LDL Receptor deficiency, Ornithine Transcarbamylase deficiency, PAX6 Mutation Phenylketonuria, RBI Gene Mutation, Tuberous Sclerosis, von Willebrand Factor Disease, and Werner Syndrome, cancer, or infectious disease.
The invention further includes various polypeptides that are created in the embodiments described above .
Further embodiments of the invention take the form of data e useful for detecting and analyzing DNA mutations and polymorphisms stored in a physical medium in computer readable form a plurality of DNA sequence fragments contained within a reference DNA sequence, and the sequences of the polypeptides encoded in said DNA sequence fragments, the predicted sequences of a plurality of polypeptides encoded in a set of transformed DNA sequence fragments, each member of said set comprised of a DNA sequence related to said DNA sequence fragment by a specific change selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution; b. means for comparing the predicted sequences of said plurality of polypeptides with a test sequence to determine identity of the test sequence with a predicted sequence.
Additional embodiments include computer data structures, comprising: data storage media; and data sets in computer readable form on the data storage media representing a plurality of polypeptide fragments of polypeptides encoded by a reference polynucleotide sequence; and second data sets in computer readable form on the data storage media representing physical properties of each of the polypeptide fragments; and means for correlating empirically derived physical properties of test polypeptides with second data sets to determine the identity of the test polypeptides. The data structures may further comprising third data sets in computer readable form on said data storage media representing polynucleotide fragments encoding the polypeptide fragments; and means for correlating the identity of the test polypeptides with polynucleotide fragments represented in the third data sets. In these data the physical properties may include mass or partial or complete amino acid composition or sequence.
In yet additional embodiments, the invention includes data structures in which reference polynucleotides have a reading frame, and wherein one data set represents polypeptide fragments encoded in frame and polypeptide fragments encoded out of frame with respect to said reference polynucleotide.
Further embodiments include computer implemented methods for ascertaining the identity of nucleic acid fragments encoding polypeptides, wherein the nucleic acid fragments are fragments of known reference sequences, comprising the steps of measuring a physical property of a polypeptide comparing, in a computer, the measured physical property with a data set representing the predicted corresponding physical properties of possible polypeptides that are encoded by fragments of the reference sequence within a predetermined size range; and identifying a match between the measured physical property and a predicted physical property in the data set; and displaying or recording the results of the identifying step. The data set may includes physical properties of polypeptides encoded by in-frame and any of six out-of-frame fragments of said reference polynucleotide.
Additional embodiments of the invention include relational data sets useful for detecting and analyzing DNA mutations and polymorphisms comprising a plurality of DNA sequence fragments contained within a reference DNA sequence, the sequences of the polypeptides encoded in said DNA sequence fragments, and the predicted sequences of a plurality of polypeptides encoded in a set of transformed DNA sequence fragments, each member of said set comprised of a DNA sequence related to said DNA sequence fragment by a specific change selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution. Further embodiments include computer programs that search of these data sets .
The computer-implemented methods of the present invention can be carried out on a general purpose computer, such as, for example, a PC running the Windows, NT, Unix, or Linux operating systems, or a Macintosh personal computer. For some embodiments of the invention, a more powerful computer mainframe would be desirable. Suitable computers typically have a central processor, computer memory (such as RAM) , and a storage medium, such as a floppy disk, a fixed disk or hard drive, a tape drive, an optical storage medium such as a CD, DVD, or WORM drive, a removable disk, or the like, which can store data in computer-readable form. Such computers typically have a means, such as a monitor, for displaying data or information, and are capable of storing program-generated data in RAM or in the storage medium. Such computers can also advantageously be connected to a printer, for providing a fixed record of information generated by the program.
A general purpose computer utilized in the present invention could be programmed with a specific program of the type described herein. In particular, this program would generate data sets of all possible nucleotide fragments, in all possible frames and in both orientations. It would predict and store data sets reflecting the translation products of those fragments. It would also store, in a correlatable manner, a data set reflecting a physical property (such as molecular weight) of each of those fragments. One program that could be used in the present invention would compare an empirically determined physical property of a polypeptide translated from a polynucleotide fragment from a biological sample with the data set to determine, for example, which possible polypeptide fragment or which possible polynucleotide fragment corresponds to the sample. In this manner, the identity of DNA in the sample can be determined.
In one embodiment, information directly or indirectly related to the identity of the polynucleotide fragment from the sample can be displayed, printed, and/or stored. This can include the exact identity or sequence of the polynucleotide, or a tag, label, or name associated therewith. It could also be a diagnosis of a disease, condition, genotype, or phenotype associated with that particular polynucleotide.
CONCLUSION, RAMIFICATIONS AND SCOPE OF INVENTION In conclusion, the invention specified here provides a novel method for analyzing cloned DNA segments and for identifying and/or assaying known or new polymorphisms or mutations in those DNA segments. The ' method has unique and highly useful advantages over all other methods the prior art .
The specific description of my invention presented above should not be construed as limiting its scope but rather as exemplification of certain embodiments thereof. Many other variations and applications are possible and can be practiced by one skilled in the art. For the purpose of expression, multiple promoters and translation start sites can be placed in the known sequence, on one or both sides thereof, so that the unknown sequence is translated in up to six different reading frames. Or the unknown sequence can be a PCR amplicon that is cloned into a vector in both orientations, thereby yielding a mixture of clones, some translated from one strand and some from the other. Or promoters and translation start signals can be incorporated near one or both ends of a transposable element, such as Tn3 , Tn5 , Tn7 , TnlO, Ty, P-element, and Mariner; of a virus such as herpes virus, adenovirus, adeno-associated virus; or of a retrovirus . Fusion protein expression need not take place in bacteria, as in the examples given here, but may take place in eucaryotic cells such as yeast or mammalian cells, and cell free expression need not take place in a rabbit reticulocyte lysate, as in the example, but in other cell free systems. Other modalities for peptide capture can be used, such as incorporating biotinylated lysine in the peptides and capturing with avidin or streptavidin. Additionally, protease recognition sites may be incorporated into the known sequence to aid in fragment preparation, such as placing an enterokinase cleavage site and a poly-histidine sequence upstream of the junction to the unknown sequence so that a peptide for analysis can be released by enterokinase treatment of an affinity captured polypeptide. Further, the DNA polymorphisms that are identified and/or detected need not be limited to single nucleotide polymorphisms, as in the examples, but could be of many other kinds such as microsattelite repeats of different lengths or specific single nucleotide deletions, single nucleotide insertions, multiple nucleotide substitutions, multiple nucleotide deletions, multiple nucleotide insertions, DNA duplications, DNA inversions, DNA translocations, DNA deletion/substitutions or other chromosomal rearrangements .

Claims

I Claim :
1. A method for determining the sequence of a polynucleotide, comprising a. providing a nucleic acid fragment having homology to a known reference sequence, and b. expressing at least one polypeptide from said fragment, and c. assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in said known reference sequence.
2. The method of claim 1 wherein said nucleic acid fragment contains a difference with respect to the reference sequence wherein said difference is selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution.
3. The method of claim 1 wherein said nucleic acid fragment comprises an exon.
4. The method of claim 1 wherein said nucleic acid fragment comprises a cDNA.
5. The method of claim 1 wherein said at least one polypeptide comprises a fragment homologous to said reference sequence and at least one predetermined heterologous epitope tag.
6. The method of claim 1 wherein said at least one polypeptide is expressed in a living cell .
7. The method of claim 1 wherein said at least one polypeptide is expressed in a cell free system.
8. The method of claim 7 wherein said cell free system is selected from the group consisting of E. coli extract, rabbit reticulocyte extract, and wheat germ extract .
9. The method of claim 1 further comprising purifying said peptide in conjunction with assessing the physical property.
10. The method of claim 9 wherein said purification comprises a method selected from the group consisting of gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography (HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S- transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaffinity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation.
11. The method of claim 1 wherein the physical property that is determined is mass .
12. The method of claim 11 wherein said mass is determined by a method selected from the group consisting of mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) ) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography (HPLC) .
13. The method of claim 1 wherein the physical property that is assessed is partial or complete amino acid composition.
14. The method of claim 1 wherein the physical property that is assessed is partial or complete amino acid sequence .
15. A method for genetic analysis, comprising a. providing a nucleic acid fragment having homology to a known reference sequence, and b. expressing at least one polypeptide from said fragment, and c. assessing at least one physical property of said at least one polypeptide to determine the coding capacity of said fragment by comparing said at least one physical property to the predicted properties of polypeptides encoded in a known reference sequence.
16. The method of claim 15 wherein said nucleic acid fragment contains a difference with respect to the reference sequence selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution.
17. The method of claim 15 wherein said nucleic acid fragment comprises an exon.
18. The method of claim 15 wherein said nucleic acid fragment comprises a cDNA.
19. The method of claim 15 wherein said at least one polypeptide contains at least one epitope tag.
20. The method of claim 15 wherein said at least one polypeptide is expressed in a living cell.
21. The method of claim 15 wherein said at least one polypeptide is expressed in a cell free system.
22. The method of claim 21 wherein said cell free system is selected from the group consisting of E. coli extract, rabbit reticulocyte extract, and wheat germ extract .
23. The method of claim 15 further comprising purification of said peptide in conjunction with assessing the physical property.
24. The method of claim 23 wherein said purification comprises a method selected from the group consisting of gel electrophoresis, capillary electrophoresis, liquid chromatography (LC) , capillary liquid chromatography, high performance liquid chromatography (HPLC) , differential centrifugation, filtration, gel filtration, membrane chromatography, affinity purification, biomolecular interaction analysis (BIA) , ligand affinity purification, glutathione-S- transferase affinity chromatography, cellulose binding protein affinity chromatography, maltose binding protein affinity chromatography, avidin/streptavidin affinity chromatography, S-tag affinity chromatography, thioredoxin affinity chromatography, metal-chelate affinity chromatography, immobilized metal affinity chromatography, epitope-tag affinity chromatography, immunoaffinity chromatography, immunoaffinity capture, capture using bioreactive mass spectrometer probes, mass spectrometric immunoassay, and immunoprecipitation.
25. The method of claim 15 wherein the physical property that is determined is mass.
26. The method of claim 25 wherein said mass is determined by a method selected from the group consisting of mass spectrometry, MALDI-TOF mass spectrometry, electrospray ionization mass spectrometry (ESI) tandem mass spectrometry (MS/MS) , quadripole time of flight spectrometry (Q-TOF) , Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, gel electrophoresis, capillary electrophoresis, and high performance liquid chromatography (HPLC) .
27. The method of claim 15 wherein the physical property that is assessed is partial or complete amino acid composition.
28. The method of claim 15 wherein the physical property that is assessed is partial or complete amino acid sequence .
29. A method for assessing a disease, condition, genotype, or phenotype, comprising a. providing a nucleic acid fragment from a biological sample, and b. expressing at least one polypeptide from said fragment , and c. assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence, and d. correlating said determined sequence with said disease, condition, genotype or phenotype.
30. The method of claim 29 wherein the original source of said biological sample is obtained from a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, secretion, blood, sweat, urine, tears, semen, saliva, feces, skin, hair or milk of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant .
31. A diagnostic or prognostic test for a disease, condition, genotype, or phenotype, comprising a. providing a nucleic acid fragment from a biological sample, b. expressing at least one polypeptide from said fragment , and c. assessing at least one physical property of said at least one polypeptide to determine the sequence of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in said known reference sequence.
32. The method of claim 31 wherein the original source of said biological sample is a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, secretion, blood, sweat, urine, tears, semen, saliva, feces, skin, hair or milk of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant .
33. The diagnostic or prognostic test of claim 31 wherein said test detects heterozygote status.
34. The diagnostic or prognostic test of claim 31 wherein said phenotype is response to a drug or therapeutic treatment.
35. The diagnostic or prognostic test of claim 31 wherein said disease is a genetic disease.
36. The diagnostic or prognostic test of claim 31 wherein the genetic disease is selected from the group consisting of Alzheimer's disease, Ataxia talangietasia
(ATM) , Familial adematous polyposis (APC) , Hereditary breast/ovarian cancer (BRCAl, BRCA2), Hereditary melanoma (CDK2, CDKN2) , Hereditary non-polypsosis colon cancer (hMSH2, hMLHl, hPMSl, hPMS2), Hereditary retinoblastoma (RBI), Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53) , Multiple endocrine neoplasia (MEN1, MEN2) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen receptor deficiency, Tetrahydrobiopterin deficiency, X-Linked agammaglobulinemia, Cystic Fibrosis (CFTR) , Diabetes, Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency,
Glucose-6-Phosphate deficiency, Pompe Disease, Hemophilia
A, Hexosaminidase A deficiency, Human Type I and Type III
Collagen deficiency X-linked SCID, Retinitis pigmentosa
(RP) LIACAM deficiency, MCAD deficiency, LDL Receptor deficiency, Ornithine Transcarbamylase deficiency, PAX6 Mutation Phenylketonuria, RBI Gene Mutation, Tuberous Sclerosis, von Willebrand Factor Disease, and Werner Syndrome .
37. The diagnostic or prognostic test of claim 31 wherein said disease is cancer.
38. The diagnostic or prognostic test of claim 31 wherein said disease is an infectious disease.
39. A method for assessing a disease, condition, genotype, or phenotype, comprising a. providing a nucleic acid fragment from a biological sample, b. expressing at least one polypeptide from said fragment, and c. assessing at least one physical property of said at least one polypeptide to determine the coding capacity of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence. d. correlating said determined sequence with said disease, condition, genotype or phenotype.
40. The method of claim 39 wherein the original source of said biological sample is a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, secretion, blood, sweat, urine, tears, semen, saliva, feces, skin, hair or milk of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant .
41. A diagnostic or prognostic test for a disease, condition, genotype, or phenotype, comprising a. providing a nucleic acid fragment from a biological sample, b. expressing at least one polypeptide from said fragment , and c. assessing at least one physical property of said at least one polypeptide to determine the coding capacity of said fragment by comparing said at least one property to the predicted properties of polypeptides encoded in a known reference sequence.
42. The test of claim 41 wherein the original source of said biological sample is a virus, organelle, cell, tissue, body part, exudate, excretion, elimination, secretion, blood, sweat, urine, tears, semen, saliva, feces, skin, hair or milk of a healthy, diseased or deceased microorganism, protist, alga, fungus, animal or plant .
43. The diagnostic or prognostic test of claim 41 wherein said test detects heterozygote status.
44. The diagnostic or prognostic test of claim 41 wherein said phenotype is response to a therapeutic drug or treatment.
45. The diagnostic or prognostic test of claim 41 wherein said disease is a genetic disease.
46. The diagnostic or prognostic test of claim 41 wherein the genetic disease is selected from the group consisting of Alzheimer's disease, Ataxia talangietasia
(ATM) , Familial adematous polyposis (APC) , Hereditary breast/ovarian cancer (BRCAl, BRCA2), Hereditary melanoma (CDK2, CDKN2) , Hereditary non-polypsosis colon cancer (hMSH2, hMLHl, hPMSl, hPMS2), Hereditary retinoblastoma (RBI), Hereditary Wilm' s Tumor (WT1) , Li-Fraumeni syndrome (p53) , Multiple endocrine neoplasia (MEN1, MEN2 ) , Von Hippel-Lindau syndrome (VHL) , Congenital adrenal hyperplasia, Androgen receptor deficiency, Tetrahydrobiopterin deficiency, X-Linked agammaglobulinemia, Cystic Fibrosis (CFTR) , Diabetes, Muscular Dystrophy (DMD, BMD) , Factor X deficiency, Mitochondrial gene deficiency, Factor VII deficiency,
Glucose- 6 -Phosphate deficiency, Pompe Disease, Hemophilia
A, Hexosaminidase A deficiency, Human Type I and Type III
Collagen deficiency X-linked SCID, Retinitis pigmentosa
(RP) LIACAM deficiency, MCAD deficiency, LDL Receptor deficiency, Ornithine Transcarbamylase deficiency, PAX6 Mutation Phenylketonuria, RBI Gene Mutation, Tuberous Sclerosis, von Willebrand Factor Disease, and Werner Syndrome .
47. The diagnostic or prognostic test of claim 41 wherein said disease is cancer.
48. The diagnostic or prognostic test of claim 41 wherein said disease is an infectious disease.
49. Said at least one polypeptide of claim 1.
50. Said at least one polypeptide of claim 15.
51. Said at least one polypeptide of claim 29.
52. Said at least one polypeptide of claim 31.
53. Said at least one polypeptide of claim 39.
54. Said at least one polypeptide of claim 41.
55. A data structure useful for detecting and analyzing DNA mutations and polymorphisms, comprising: a. data representing the following stored in a physical medium in computer readable form: i. a plurality of DNA sequence fragments contained within a reference DNA sequence, and ii . the sequences of the polypeptides encoded in said DNA sequence fragments, and iii. the predicted sequences of a plurality of polypeptides encoded in a set of transformed DNA sequence fragments, each member of said set comprised of a DNA sequence related to said DNA sequence fragment by a specific change selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution; b. means for comparing the predicted sequences of said plurality of polypeptides with a test sequence to determine identity of the test sequence with a predicted sequence .
56. A computer data structure, comprising: a data storage medium; a first data set in computer readable form on said data storage medium representing a plurality of polypeptide fragments of a polypeptide encoded by a reference polynucleotide sequence; a second data set in computer readable form on said data storage medium representing a physical property of each of said polypeptide fragments; and means for correlating an empirically derived physical property of a test polypeptide with the second data set to determine the identity of the test polypeptide.
57. The data structure of claim 56 further comprising a third data set in computer readable form on said data storage medium representing polynucleotide fragments encoding said polypeptide fragments; and means for correlating the identity of the test polypeptide with a polynucleotide fragment represented in said third data set .
58. The data structure of claim 56 wherein said physical property is mass.
59. The data structure of claim 56 wherein said reference polynucleotide has a reading frame, and wherein said first data set represents polypeptide fragments encoded in frame and polypeptide fragments encoded out of frame with respect to said reference polynucleotide.
60. A computer implemented method for ascertaining the identity of a nucleic acid fragment encoding a polypeptide, wherein the nucleic acid fragment is a fragment of a known reference sequence, comprising the steps of : measuring a physical property of said polypeptide; comparing, in a computer, the measured physical property with a data set representing the predicted corresponding physical properties of possible polypeptides that are encoded by fragments of said reference sequence within a predetermined size range; identifying a match between said measured physical property and a predicted physical property in the data set; and displaying or recording the results of the identifying step.
61. The method of claim 60 wherein said reference polynucleotide has a frame, and said data set includes physical properties of polypeptides encoded by out-of-frame fragments of said reference polynucleotide.
62. The method of claim 60 wherein said reference polynucleotide has six possible frames, and said data set includes physical properties of polypeptides encoded by fragments having at least one of said possible frames .
63. A relational data set useful for detecting and analyzing DNA mutations and polymorphisms comprising, a. a plurality of DNA sequence fragments contained within a reference DNA sequence, b. the sequences of the polypeptides encoded in said DNA sequence fragments, and c. the predicted sequences of a plurality of polypeptides encoded in a set of transformed DNA sequence fragments, each member of said set comprised of a DNA sequence related to said DNA sequence fragment by a specific change selected from the group consisting of single nucleotide polymorphism, single nucleotide substitution, single nucleotide deletion, single nucleotide insertion, multiple nucleotide substitution, multiple nucleotide deletion, multiple nucleotide insertion, DNA duplication, DNA inversion, DNA translocation, and DNA deletion/substitution.
64. A computer program comprising a search of the data set of claim 63.
PCT/US1999/030104 1998-12-16 1999-12-16 Methods and products for peptide-based dna sequence characterization and analysis WO2000036414A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP99968909A EP1151296A4 (en) 1998-12-16 1999-12-16 Methods and products for peptide-based dna sequence characterization and analysis
AU27107/00A AU2710700A (en) 1998-12-16 1999-12-16 Methods and products for peptide-based dna sequence characterization and analysis
CA002355134A CA2355134A1 (en) 1998-12-16 1999-12-16 Methods and products for peptide-based dna sequence characterization and analysis
US09/788,268 US20020155445A1 (en) 1999-12-16 2001-02-16 Methods and products for peptide based DNA sequence identification and analysis

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US11235198P 1998-12-16 1998-12-16
US60/112,351 1998-12-16

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US09/788,268 Continuation-In-Part US20020155445A1 (en) 1999-12-16 2001-02-16 Methods and products for peptide based DNA sequence identification and analysis

Publications (1)

Publication Number Publication Date
WO2000036414A1 true WO2000036414A1 (en) 2000-06-22

Family

ID=22343436

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1999/030104 WO2000036414A1 (en) 1998-12-16 1999-12-16 Methods and products for peptide-based dna sequence characterization and analysis

Country Status (4)

Country Link
EP (1) EP1151296A4 (en)
AU (1) AU2710700A (en)
CA (1) CA2355134A1 (en)
WO (1) WO2000036414A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105588909A (en) * 2015-12-15 2016-05-18 中国肉类食品综合研究中心 Method for determining multiple kinds of animal origin meat based on liquid chromatographic-tandem mass spectrometric technology
CN113945649A (en) * 2021-08-18 2022-01-18 中国农业科学院农业质量标准与检测技术研究所 Proteome biomarker of milk with different processing technologies and screening method and application thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5620848A (en) * 1990-06-27 1997-04-15 Trustees Of Princeton University Methods for detecting mutant p53
US5702890A (en) * 1993-07-26 1997-12-30 K.O. Technology, Inc. Inhibitors of alternative alleles of genes as a basis for cancer therapeutic agents
US5876940A (en) * 1994-11-30 1999-03-02 University Of Utah Research Foundation Alleles

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6017693A (en) * 1994-03-14 2000-01-25 University Of Washington Identification of nucleotides, amino acids, or carbohydrates by mass spectrometry
US6207370B1 (en) * 1997-09-02 2001-03-27 Sequenom, Inc. Diagnostics based on mass spectrometric detection of translated target polypeptides

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5620848A (en) * 1990-06-27 1997-04-15 Trustees Of Princeton University Methods for detecting mutant p53
US5702890A (en) * 1993-07-26 1997-12-30 K.O. Technology, Inc. Inhibitors of alternative alleles of genes as a basis for cancer therapeutic agents
US5876940A (en) * 1994-11-30 1999-03-02 University Of Utah Research Foundation Alleles

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
LODISH H, DARNELL J, BALTIMORE D: "MOLECULAR CELL BIOLOGY", MOLECULAR CELL BIOLOGY, XX, XX, 1 January 1986 (1986-01-01), XX, pages 107 - 110, XP002926856 *
See also references of EP1151296A4 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105588909A (en) * 2015-12-15 2016-05-18 中国肉类食品综合研究中心 Method for determining multiple kinds of animal origin meat based on liquid chromatographic-tandem mass spectrometric technology
CN105588909B (en) * 2015-12-15 2020-08-25 中国肉类食品综合研究中心 Method for determining various animal-derived meats based on liquid chromatography tandem mass spectrometry technology
CN113945649A (en) * 2021-08-18 2022-01-18 中国农业科学院农业质量标准与检测技术研究所 Proteome biomarker of milk with different processing technologies and screening method and application thereof
CN113945649B (en) * 2021-08-18 2023-08-18 中国农业科学院农业质量标准与检测技术研究所 Proteome biomarker of milk with different processing technologies, screening method and application thereof

Also Published As

Publication number Publication date
EP1151296A4 (en) 2005-01-26
CA2355134A1 (en) 2000-06-22
EP1151296A1 (en) 2001-11-07
AU2710700A (en) 2000-07-03

Similar Documents

Publication Publication Date Title
Morrissy et al. Spatial heterogeneity in medulloblastoma
JP6386494B2 (en) Fetal genome analysis of maternal biological samples
Cortés-Ciriano et al. Computational analysis of cancer genome sequencing data
Frenkel-Morgenstern et al. Chimeras taking shape: potential functions of proteins encoded by chimeric RNA transcripts
CN112397144B (en) Method and device for detecting gene mutation and expression quantity
EP2080812A1 (en) Compositions and methods of detecting post-stop peptides
Dolled-Filhart et al. Computational and bioinformatics frameworks for next-generation whole exome and genome sequencing
US20020155445A1 (en) Methods and products for peptide based DNA sequence identification and analysis
JP2023504529A (en) Systems and methods for automating RNA expression calls in cancer prediction pipelines
Patel et al. MinION rapid sequencing: Review of potential applications in neurosurgery
US8530638B2 (en) Space efficient polymer sets
CN105886605B (en) The amplimer and detection method of PKD2 detection in Gene Mutation
Kelly et al. A multi-omic dissection of super-enhancer driven oncogenic gene expression programs in ovarian cancer
EP3432176A1 (en) Scansoft: a method for the detection of genomic deletions and duplications in massive parallel sequencing data
Sezerman et al. Bioinformatics workflows for genomic variant discovery, interpretation and prioritization
Batavia et al. Biallelic ELOC-inactivated renal cell carcinoma: molecular features supporting classification as a distinct entity
EP1151296A1 (en) Methods and products for peptide-based dna sequence characterization and analysis
Aly et al. From fuzziness to precision medicine: on the rapidly evolving proteomics with implications in mitochondrial connectivity to rare human disease
US20050233319A1 (en) Methods and products for peptide-based cDNA characterization and analysis
WO2001061028A2 (en) Methods and products for peptide based dna sequence identification and analysis
KR102452413B1 (en) Method for detecting chromosomal abnormality using distance information between nucleic acid fragments
KR101977976B1 (en) Method for increasing read data analysis accuracy in amplicon based NGS by using primer remover
AU5437001A (en) Methods and products for peptide-based DNA sequence characterization and analysis
JP2022544626A (en) Chromosomal aberration detection method using distance information between nucleic acid fragments
US20230332205A1 (en) Linked dual barcode insertion constructs

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 09788268

Country of ref document: US

ENP Entry into the national phase

Ref document number: 2355134

Country of ref document: CA

Ref country code: CA

Ref document number: 2355134

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 1999968909

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWP Wipo information: published in national office

Ref document number: 1999968909

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1999968909

Country of ref document: EP