EP1463841A2 - Procede de detection de modeles de methylation de la cytosine par ligation exponentielle d'oligonucleotides sondes hybrides (mla) - Google Patents

Procede de detection de modeles de methylation de la cytosine par ligation exponentielle d'oligonucleotides sondes hybrides (mla)

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Publication number
EP1463841A2
EP1463841A2 EP03704206A EP03704206A EP1463841A2 EP 1463841 A2 EP1463841 A2 EP 1463841A2 EP 03704206 A EP03704206 A EP 03704206A EP 03704206 A EP03704206 A EP 03704206A EP 1463841 A2 EP1463841 A2 EP 1463841A2
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Prior art keywords
dna
probe oligonucleotides
probe
examined
linked
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German (de)
English (en)
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Kurt Berlin
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Epigenomics AG
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Epigenomics AG
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    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12Q—MEASURING 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
    • C12Q1/00—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/68—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
    • C12Q1/6844—Nucleic acid amplification reactions
    • C12Q1/6858—Allele-specific amplification

Definitions

  • the present invention relates to a method for the detection of cytosine methylation in DNA samples.
  • 5-Methylcytosine is the most common covalently modified base in the DNA of eukaryotic cells. For example, it plays a role in the regulation of transcription, in genetic imprinting and in tumorigenesis. The identification of 5-methylcytosine as a component of genetic information is therefore of considerable interest. However, 5-methylcytosine positions cannot be identified by sequencing, since 5-methylcytosine has the same base pairing behavior as cytosine. In addition, in the case of PCR amplification, the epigenetic information which the 5-methylcytosins carry is completely lost.
  • a relatively new and the most frequently used method for the examination of DNA for 5-methyl-cytosine is based on the specific reaction of bisulfite with cytosine, which is subsequently se is converted into uracil, which corresponds to the thymidine in its base pairing behavior.
  • 5-methylcyto-sin is not modified under these conditions. This transforms the original DNA into methylcytosine, which is originally due to be
  • Hybridization behavior from cytosine can not be distinguished, now by "normal" molecular biological techniques as the only remaining cytosine can be detected, for example by amplification and hybridization or sequencing. All of these techniques are based on base pairing, which is now being fully exploited
  • Sensitivity is defined by a process that includes the DNA to be examined in an agarose matrix, thereby preventing the diffusion and renaturation of the DNA (bisulfite only reacts on single-stranded DNA) and replacing all precipitation and purification steps with rapid dialysis (Olek A , Oswald J, Walter J. A modified and proven method for bisulphate based cytosine methylation analysis. Nucleic Acids Res. 1996 DEC 15; 24 (2): 5064-6).
  • Urea improves the efficiency of bisulfite treatment before sequencing 5-methylcytosine in genomic DNA (Paulin R, Grigg GW, Davey MW, Piper AA. Urea improves efficiency of bisulphate-mediated sequencing of 5'-methylcytosine in genomic DNA. Nucleic Acids Res. 1998 Nov. 1; 26 (21): 5009-10).
  • Genomic sequencing indicates a correlation between DNA hypomethylation in the 5 'region of the pS2 gene andin its expression in human breast cancer cell lines. Genes. 1995 May 19; 157 (1-2): 261-4; WO 97 46705, WO 95 15373 and WO 45560.
  • methylation-sensitive PCR (Herman JG, Graff JR, Myohanen S, Nelkin BD, Baylin SB. (1996), Methylation-specific PCR: a novel PCR assay for methylation Status of CpG islands. Proc Natl Acad Sei US A. Sep 3; 93 (18): 9821-6).
  • primers are used which either hybridize only to a sequence which results from the bisulfite treatment of a DNA which is unmethylated at the position in question, or conversely primers which only bind to a nucleic acid which is caused by the bisulfite -Treatment of a DNA unmethylated at the position in question arises. With these primers, amplicons can accordingly be generated, the detection of which in turn provides evidence of the presence of a methylated or unmethylated position in the sample to which the primers bind.
  • a newer method is also the detection of cytosine methylation by means of a Taqman PCR, which has become known as MethylLight (WO00 / 70090). With this method it is possible to check the methylation status of individual or fewer positions directly in the course of the PCR. assign, so that a subsequent analysis of the products is unnecessary.
  • Matrix-assisted laser desorption / ionization mass spectrometry is a very powerful development for the analysis of biomolecules (Karas M, Hillenkamp F. Laser desorption ionization of proteins with molecular masses exceeding 10,000 daltons. Anal Chem. 1988 Oct. 15; 60 (20): 2299-301).
  • An analyte is embedded in a light-absorbing matrix. The matrix is evaporated by a short laser pulse and the analyte molecule is thus transported unfragmented into the gas phase. The ionization of the analyte is achieved by collisions with matrix molecules.
  • An applied voltage accelerates the ions into a field-free flight tube. Due to their different masses, ions are accelerated to different extents. Smaller ions reach the detector earlier than larger ones.
  • MALDI-TOF spectroscopy is excellently suited for the analysis of peptides and proteins.
  • the analysis of nucleic acids is somewhat more difficult (Gut, IG and Beck, S. (1995), DNA and Matrix Assisted Laser Desorption Ionization Mass Spectrometry. Molecular Biology: Current Innovations and Future Trends 1: 147-157.)
  • the sensitivity is about 100 times worse than for peptides and decreases disproportionately with increasing fragment size.
  • nucleic acids that have a backbone that is often negatively charged the ionization process through the matrix is much more inefficient.
  • Genomic DNA is obtained by standard methods from DNA from cell, tissue or other test samples. This standard methodology can be found in references such as Fritsch and Maniatis, Molecular Cloning: A Laboratory Manual, 1989. Methods for amplifying DNA fragments are state of the art. The most frequently used method, the polymerase chain reaction (PCR), is mainly used to amplify discrete fragments of genomic DNA using two primers. The above-mentioned method for methylation detection, MSP, also uses this method. Other methods for the detection of methylation, which are based on bisulfite-treated DNA, also use PCR as an amplification method in order to overcome sensitivity problems.
  • PCR polymerase chain reaction
  • LCR ligase chain reaction
  • EP0320308 and EP0439182. The latter describes a combination of the LCR with a polymerase reaction.
  • both primers are selected so that they usually cover several methylable positions to be examined for their methylation status. Only when these mostly 3 or more positions have essentially the same methylation status (eg all methylated), does the primer hybridize to the position in question in the template and an amplification by means of PCR can take place. If both primers are selected in this way, it is possible to achieve very high sensitivity of the method. For example, 1 continuous methylated template can be detected in a background of 10,000 unmethylated templates, since the unmethylated templates are not amplified when appropriately specific primers are used.
  • a disadvantage of the method is its sequence dependency. It is necessary to find precisely those positions that are co-methylated in order to achieve the corresponding sensitivities. If the CpG positions are too far apart, very long primers are required, which in turn can be disadvantageous for the PCR itself and can also be disadvantageous for the sensitivity. The annealing temperature of such primers is then very high. It is also required to generate a methylation sensitive
  • MLA methylation-sensitive ligation and amplification
  • the present invention is therefore a method which overcomes disadvantages of the prior art in the area of methylation detection. It can be used for amplification and indirect detection of the methylation status of a group of CpG positions.
  • this can also be used for the selective amplification of a DNA to be examined with a certain methylation status in the presence of sequence-homologous background DNA with a different methylation status.
  • DNA to be examined and background DNA in the sense of this invention are to be explained using the example of the prior art (MSP).
  • the DNA to be examined as well as the nucleic acids otherwise present, hereinafter referred to as background DNA, are otherwise amplified equally, since the primers used are also not able to distinguish between DNA to be examined and background DNA.
  • One possibility to differentiate these DNAs arises from the different methylation pattern.
  • a common procedure is the methylation sitive PCR, short MSP (Herman JG, Graff JR, Myohanen S, Nelkin BD, Baylin SB. (1996), Methylation-specific PCR: a novel PCR assay for methylation Status of CpG islands. Proc Natl Acad Sei US A.
  • the object is achieved by a method for the detection of cytosine methylation in DNA samples, the following steps being carried out: a) a genomic DNA sample is treated in such a way that the unmethylated cytosine bases are converted into uracil while the 5- Methylcytosine bases remain unchanged; b) the chemically treated DNA sample is amplified using at least 2 pairs of essentially complementary probe oligonucleotides and a ligase and c) the amplificates are analyzed and the presence of an amplificate indicates the methylation status in the DNA to be examined.
  • the DNA to be examined is preferred as the template to the sequence-homologous background DNA.
  • the analysis of further positions in the amplificate indicates the methylation status in the DNA to be examined.
  • step b) the probe oligonucleotides hybridize to a template when those covered by them
  • CpG positions in the genomic DNA sample (or the DNA to be investigated) were methylated and the same probe oligonucleotides hybridize to templates that were completely or partially unmethylated at these positions to a much lesser extent.
  • step b) the probe oligonucleotides hybridize to a template if the CpG positions covered by them in the genomic DNA sample (or the DNA to be examined) were unmethylated and the same probe oligonucleotides were present Hybridize templates that were fully or partially methylated at these positions to a much lesser extent.
  • step b) is carried out in detail as follows: a) the probe oligonucleotides which hybridized at adjacent positions on the template are linked to one another by ligation, b) the linked probe oligonucleotides are dehybridized, c) the probe oligonucleotides complementary to the linked probe oligonucleotides hybridize to the already linked probe oligonucleotides and are in turn linked by ligation, and d) the linked probe oligonucleotides serve as templates for further ligation steps, so that a further proliferation of the linked oligonucleotides he follows.
  • At least one of the probe oligonucleotides carries a phosphate group at the 5 'end.
  • At least one of the probe oligonucleotides is provided with a detectable label, in particular is provided with a label which can be detected by fluorescence. It is particularly preferred that at least two probe oligonucleotides are provided with labels, these changing their properties depending on their distance from one another. It is particularly preferred that the probe oligonucleotides carry at least one fluorescent label. It is further preferred that the probe molecules indicate the amplification either by an increase or a decrease in the fluorescence. In particular, it is preferred according to the invention that the increase or decrease in the fluorescence is also used directly for the analysis and a conclusion is drawn from the changed fluorescence signal that the DNA to be examined is methylated.
  • the background DNA prefferably present in a 100-fold concentration in comparison to the DNA to be examined. It is also preferred that the rear basic DNA is present in 1000-fold concentration compared to the DNA to be examined.
  • the DNA samples are obtained from serum or other body fluids of an individual. It is also preferred according to the invention that the DNA samples from cell lines, blood, sputum, stool, urine, serum, brain-spinal cord fluid, tissue embedded in paraffin, for example tissue from the eyes, intestine, kidney, brain, heart, prostate, lung , Breast or liver, histological slides and all possible combinations thereof.
  • the chemical treatment is carried out after embedding the DNA in agarose.
  • a reagent denaturing the DNA duplex and / or a radical scavenger is present during the chemical treatment.
  • the analysis step c) is carried out by means of hybridization on oligomer arrays, where 0-ligomeric nucleic acids or their hybridization properties can be molecules similar to PNAs.
  • the analysis in step c) is carried out by measuring the length of the amplified DNA to be examined, methods for measuring the length comprising gel electrophoresis, capillary gel electrophoresis, chromatography (e.g. HPLC), mass spectrometry and other suitable methods.
  • methods for measuring the length comprising gel electrophoresis, capillary gel electrophoresis, chromatography (e.g. HPLC), mass spectrometry and other suitable methods.
  • step c) is carried out by sequencing, with measurement Methods for sequencing include the Sanger method, Maxam-Gilbert method and other methods such as Sequencing by Hybridization (SBH).
  • the methylation status at the various CpG positions examined indicates the presence of a disease or another medical condition of the patient.
  • the amplified products are provided with a detectable label even for the detection. It is particularly preferred that the markings are fluorescent markings. It is also preferred that the markings are radionuclides. It is particularly preferred according to the invention that the markings are removable mass markings which are detected in a mass spectrometer. However, it is also particularly preferred that the amplified products as a whole are detected in the mass spectrometer and are therefore clearly characterized by their mass.
  • a blocker oligonucleotide in addition to the probe oligonucleotides, a blocker oligonucleotide is used, which preferably binds to the background DNA and hinders the hybridization of the probe oligonucleotides to the background DNA. It is particularly preferred that two complementary blocker oligonucleotides (or blocker PNAs, generally blocker molecules) are used. Furthermore, it is particularly preferred that the blocker molecules bind preferentially to template strands whose sequence corresponds to a methylated DNA after treatment according to step a). It is also preferred that the blocker molecules bind preferentially to template strands which in their sequence correspond to unmethylated DNA after treatment according to step a).
  • the blocker molecules preferably that the blocker molecules bind to several CpG positions in the template DNA or that the blocker molecules bind to several TpG or CpA positions in the template DNA. It is further preferred according to the invention that the blocker oligonucleotides are modified at their 3 'end and cannot be significantly degraded by a polymerase with nuclease activity.
  • a method is preferred, step b) being carried out in detail as follows: a) the probe oligonucleotides (probe) hybridize at positions on the template strand such that between the 3 'end of the first probe and the 5' end of the a gap of at least one base remains in the second probe, b) the 3 'end of the first probe is extended by a polymer reaction, in each case complementary nucleotides being incorporated into the template strand, c) the extended first probe is extended with the one second probe linked by ligation, d) the linked probe oligonucleotides are dehybridized, e) the probe oligonucleotides complementary to the linked probe oligonucleotides hybridize to the already linked probe oligonucleotides and are in turn linked by ligation and f) the linked probe oligonucleotides serve as templates for further ligation steps, so that another increase in the linked probe oligonucleotides.
  • a heat-stable ligase is used.
  • several sets of oligonucleotide probes are used for several groups of methylation positions and thus multiplexing the assay is achieved.
  • the present invention also relates to the use of a method according to the invention for diagnosing and / or predicting adverse events for patients or individuals, these adverse events belonging to at least one of the following categories: undesirable drug effects; Cancers; CNS malfunction, damage or illness; Symptoms of aggression or behavioral disorders; clinical, psychological and social consequences of brain damage; psychotic disorders and personality disorders; Dementia and / or associated syndromes; cardiovascular disease, malfunction and damage; Malfunction, damage or disease of the gastrointestinal tract; Malfunction, damage or disease of the respiratory system; Injury, inflammation, infection, immunity and / or convalescence; Malfunction, damage or illness of the body as a deviation in the development process; Malfunction, damage or disease of the skin, muscles, connective tissue or bones; endocrine and metabolic dysfunction, injury or illness; Headache or sexual malfunction. It is preferred to use a method according to the invention for differentiating cell types or tissues or for examining cell differentiation.
  • the present invention also relates to a kit consisting of a reagent containing bisulfite, labeled oligonucleotide probes, a preferably thermostable ligase and buffers and optionally instructions for carrying out an assay according to the invention.
  • the object of the invention to provide a sensitive method for methylation analysis which overcomes disadvantages of the prior art is achieved by creating a method for the detection of cytosine methylation in DNA samples by performing the following steps:
  • a genomic DNA sample is treated in such a way that the unmethylated cytosine bases are converted into uracil while the 5-methylcytosine bases remain unchanged,
  • the chemically treated DNA sample is amplified using at least 2 pairs of essentially complementary probe oligonucleotides and a ligase, and
  • Step the DNA to be examined is preferred over the background DNA as a template.
  • the analysis of further positions in the amplificate indicates the methylation status in the DNA to be examined.
  • the second step of the method is particularly preferably carried out as follows:
  • the probe oligonucleotides hybridize to the template if the CpG positions covered by them in the genomic DNA sample (or the DNA to be examined) were methylated and to templates which were completely or partially unmethylated at these positions, if the hybridization of the probe oligonucleotides takes place to a substantially lesser extent, b) the probe oligonucleotides which hybridized at adjacent positions on the template are linked to one another by ligation, c) the linked probe oligonucleotides are dehybridized, d) the probe oligonucleotides complementary to the linked probe oligonucleotides hybridize to the already linked probe oligonucleotides and are in turn linked by ligation and e) the linked probe oligonucleotides serve as a template for further ligation steps, so that the linked probe oligonucleotides are expanded exponentially.
  • the probe oligonucleotides hybridize to the template when the CpG positions covered by them in the genomic DNA sample (or the DNA to be investigated) were unmethylated and the templates were present in those positions which were wholly or partly methylated, the hybridization takes place the probe oligonucleotides take place to a much lesser extent, b) the probe oligonucleotides which hybridized at adjacent positions on the template are linked to one another by ligation, c) the linked probe oligonucleotides are dehybridized, d) the probe oligonucleotides complementary to the linked probe oligonucleotides hybridize to those already linked Probe oligonucleotides and are in turn linked by ligation and e) the linked probe oligonucleotides serve as a template for further ligation steps, so that the linked probe oligonucleotides are expanded exponentially.
  • the methylation-sensitive step is the neighboring methylation-sensitive (on the corresponding bisulfite-treated DNA) hybridization of two probe oligonucleotides in step a). Once ligation has taken place, these linked oligonucleotides are amplified exponentially.
  • one of the probe oligonucleotides should have a terminal phosphate group. Otherwise, this must be inserted in a separate phosphorylation step.
  • the DNA samples are obtained from serum or other body fluids of an individual.
  • DNA samples from cell lines, blood, sputum, stool, urine, serum, brain-spinal fluid, paraffin-embedded tissue for example tissue from the eyes, intestine, kidney, brain, Heart, prostate, lungs, chest or liver, histological slides and all possible combinations of these wins.
  • the degree of methylation at the various CpG positions examined indicates the presence of a disease or another medical condition of the patient.
  • reporter molecules indicate the amplification either by an increase or a decrease in the fluorescence. It is particularly advantageous that the increase or decrease in fluorescence is also used directly for the analysis and a conclusion is drawn from the fluorescence signal that the DNA to be analyzed is in a methylated state.
  • Fluorescence energy transfer can either stimulate one dye, provided it is in spatial proximity to the other and the other is excited, to fluoresce. On the other hand, it is also possible for one dye to suppress the fluorescence of the other if it is spatially adjacent to it (quenching). Both methods can be used to visualize the progress of the MLA. Analogously, the methods are used in PCR as Taqman or Lightcycler assays.
  • the background DNA is present in a 100-fold concentration in comparison to the DNA to be examined. It is further preferred that the background DNA is in 1000 times the concentration compared to the DNA to be examined.
  • oligomers can be nucleic acids or their hybridization properties can be molecules similar to PNAs (peptide nucleic acids).
  • the analysis or, if appropriate, the further analysis is carried out by measuring the length of the amplified linked probe oligonucleotides, methods for measuring the length comprising gel electrophoresis, capillary gel electrophoresis, chromatography (e.g. HPLC), mass spectrometry and other suitable methods.
  • methods for measuring the length comprising gel electrophoresis, capillary gel electrophoresis, chromatography (e.g. HPLC), mass spectrometry and other suitable methods.
  • the amplified products are provided with a detectable label even for the detection. It is also advantageous that the markings are fluorescent markings, and / or that the markings are radionuclides or / and that the markings are detachable mass markings that are detected in a mass spectrometer.
  • the amplificates carry markings such as biotin, for example, so that they can be selectively bound to solid phases.
  • an oligonucleotide probe labeled with biotin and a fluorescence-labeled oligonucleotide probe are linked to one another and the products are then bound to, for example, streptavidin.
  • a fluorescence signal of the bound species can therefore only be measured if a linkage has taken place. The fluorescence signal is in through the method given limits proportional to the number of ligations that took place.
  • the amplificates are detected overall in the mass spectrometer and are therefore clearly characterized by their mass.
  • Another object of the present invention is the use of a method according to the invention for the diagnosis and / or prognosis of adverse events for patients or individuals, these adverse events belonging to at least one of the following categories: undesirable drug effects; Cancers; CNS malfunction, damage or illness; Symptoms of aggression or behavioral disorders; clinical, psychological and social consequences of brain damage; psychotic disorders and personality disorders; Dementia and / or associated syndromes; cardiovascular disease, malfunction and damage; Malfunction, damage or disease of the gastrointestinal tract; Malfunction, damage or disease of the respiratory system; Injury, inflammation, infection, immunity and / or convalescence; Malfunction, damage or illness of the body as a deviation in the development process; Malfunction, damage or disease of the skin, muscles, connective tissue or bones; endocrine and metabolic dysfunction, injury or illness; Headache or sexual malfunction.
  • the present invention also relates to a kit consisting of a reagent containing bisulfite, labeled oligonucleotide probes, a preferably thermostatic bile ligase and buffers and optionally instructions for performing an assay according to the invention
  • the preferred method consists of several steps, which can be summarized as follows:
  • a DNA serum and / or other body fluids are removed from the patient and the DNA contained therein is isolated if necessary.
  • an amplifying ligation is now carried out, in which the DNA to be examined is preferably amplified, but not or only to a lesser extent the background DNA. In any case, the amplification takes place depending on whether a certain methylation status on at least one DNA fragment in the
  • Sample is present, such as, for example, preferably all methylp CpG positions in the positions bind to the probe oligonucleotides.
  • the amplified fragments are now identified and the methylation status in the genomic DNA sample is inferred. From this, it is preferably concluded that there is a disease or another medical condition of the patient.
  • the genomic DNA used in the method is preferably obtained from a DNA sample, sources of DNA e.g. B. cell lines, blood, sputum, stool, urine, serum, brain spinal fluid, paraffin-embedded tissue, for example tissue from the eyes, intestine, kidney, brain, heart, prostate, lungs, breast or liver, histological slides and all possible combinations here of include. Isolation of DNA from body fluids of an individual, such as sputum, serum, plasma, whole blood, urine or ejaculate, is particularly preferred.
  • sources of DNA e.g. B. cell lines, blood, sputum, stool, urine, serum, brain spinal fluid, paraffin-embedded tissue, for example tissue from the eyes, intestine, kidney, brain, heart, prostate, lungs, breast or liver, histological slides and all possible combinations here of include.
  • Isolation of DNA from body fluids of an individual such as sputum, serum, plasma, whole blood, urine or ejaculate, is particularly preferred.
  • the DNA is purified or concentrated prior to the bisulfite treatment in order to avoid disrupting the bisulfite reaction and / or the subsequent PCR due to an excessive level of impurities.
  • a PCR can be carried out from tissue after treatment, for example with Proteinase K, without further purification, and this also applies mutatis mutandis to the bisulfite treatment and subsequent PCR.
  • a bisulfite hydrogen sulfite, disulfite
  • sodium bisulfite ammonium bisulfite is less suitable.
  • the reaction is carried out according to a published variant, the embedding of the DNA in agarose is preferred in order to keep the DNA in a single-stranded state during the treatment, or else according to a new variant by treatment in the presence of a radical scavenger and a denaturing reagent, preferably one Oligeothylene glycol dialkyl ether or, for example, dioxane.
  • the reagents are either removed by washing in the case of the agarose method or a DNA purification method (prior art, precipitation or binding to a solid phase, membrane) or simply brought into a concentration range by dilution which PCR no longer significantly affected.
  • the methylation positions to be investigated are selected and suitable probe oligonucleotides are selected which selectively amplify the assays to be investigated. allow appropriate DNA.
  • the positions are selected either on the premise that they should differ as much as possible between the background DNA and the DNA to be investigated with regard to their methylation, or the presence of such methylation in a large part of the DNA samples already for a disease or suggests a certain other medical condition of an individual.
  • the methylation profiles of the sections of a gene in question are first determined both for the DNA to be examined from diseased individuals and for the background DNA from healthy individuals.
  • positions which have the greatest differences between the DNA to be examined and background DNA are selected as the positions to be examined.
  • Such positions are already known for a large number of genes, for example for GSTpi, for HIC-1 and MGMT (from Wronski MA, Harris LC, Tano K, Mitra S, Bigner DD, Brent TP. (1992) Cytosine methylation and suppression of 06 -methylguanine-DNA methyltransferase expression in human rhabdomyosarcoma cell lines and xenografts.
  • DNA (which then only occurs in diseased individuals) is present in ethyl form. If probe oligonucleotides are used in the MLA which preferentially bind to the sequence which is formed in the bisulfite treatment from unmethylated background DNA, a ligation product is only produced if at least a small amount of DNA to be examined is present at all ,
  • Detection techniques that are also suitable for the detection of the amplified products are hybridization on oligomer arrays and, for example, primer extension (mini-sequencing) reactions.
  • the hybridization to oligomer arrays can be used without further modification of protocols compared to the closest prior art (Olek A, Olek S, Walter J; WO 99/28498 AI).
  • the amplificate or the amplificates is particularly preferably fluorescent or radioactive or labeled with detachable mass tags, so that after the hybridization, the fragments bound to the two oligonucleotides of a pair can be detected and quantified using this label.
  • oligomers which do not bind at CpG positions to control the experiment. These bind to ligation products of non-methylation-sensitive probe oligonucleotides, which are used for quality control and / or quantification of the sample DNA.
  • a particularly preferred variant of the method is the use of Taqman or Lightcycler technology variants for real-time detection of the amplification.
  • This change in fluorescence during amplification which is dependent on the methylation status, can be achieved by numerous methods.
  • probe oligonucleotides can be used which specifically bind either to a sequence which has been produced by chemical treatment from a DNA unmethylated at the corresponding position, or correspondingly to a sequence which has been produced by chemical treatment from a DNA methylated at the corresponding position is.
  • these probes must hybridize adjacent to one another.
  • These probes are particularly preferably provided with two different fluorescent dyes, a quencher dye and a fluorescent dye serving as a marker.
  • the quencher dye and the fluorescent dye serving as a marker are brought into contact by ligation of the two probes. As a result, a decrease in the fluorescence of the marker dye is immediately visible.
  • Different fluorescent dyes with different emission wavelengths are preferred on several special which are used together with various quenching probes in order to differentiate between the probes and thus multiplexing.
  • two competing probe pairs with different dyes can preferably also be used, one again in the case of an unmethylated position in the DNA to be examined, the other vice versa
  • hybridization is preferred.
  • the ratio of the increase in fluorescence for the two dyes can then be used to infer the degree of methylation of the examined position.
  • FRET fluorescence resonance energy transfer
  • This method can also be used analogously for the MLA, except that in this case the two probes are linked after the ligation and no longer separate in the subsequent denaturation step.
  • a fluorescence-labeled probe is hybridized to the chemically treated DNA in question at a CpG position, and the binding of this probe in turn depends on whether the DNA to be examined was methylated or unmethylated at this position.
  • Immediately adjacent beard to this probe binds another probe with a different fluorescent dye. This binding is preferably in turn dependent on methylation if there is a further methylatable position in the relevant sequence section.
  • the DNA is now amplified during the amplification, which is why more and more fluorescence-labeled probes hybridize adjacent to the position in question and are linked to one another, provided that this has the required methylation state, and therefore an increasing FRET is measured.
  • each of the 0-ligonucleotide probes used hybridizes to a sequence which contained at least two CpG dinucleotides before the treatment according to step 1 of the method according to the invention. It is again particularly preferred to design the probes such that as many CG positions as possible are located in the sequence section to which the two oligonucleotide probes hybridize.
  • multiplexing is preferably carried out with a plurality of differently fluorescence-labeled probes.
  • one of the neighboring hybridizing probes each contains a specific label, such as a quencher dye, and the other, depending on the sequence, a different label specific to the respective sequence, such as a fluorescent dye.
  • a specific label such as a quencher dye
  • a different label specific to the respective sequence such as a fluorescent dye.
  • the main difference between the two methods is that a decrease in fluorescence is measured in one case and an increase in fluorescence in the other case during amplification.
  • At least one oligonucleotide probe is extended in addition to the ligation step, which further increases the specificity of the amplification method.
  • the oligonucleotide probes do not hybridize directly adjacent to one another, but at a short distance from one another, particularly preferably 1-10 bases.
  • This gap is filled by a polymerase reaction with nucleotides.
  • This extension by means of an additionally used polymerase can either be methylation-specific if there is a CpG dinucleotide at the position in question in the untreated DNA, or it can only increase the sequence specificity.
  • the extension is preferably carried out over either only one or a relatively small number of bases, particularly preferably between 1 and 10 bases.
  • the oligonucleotide probes directly adjoin the CG position to be examined.
  • One of the oligonucleotide probes particularly preferably overlaps with a base of the CG dinucleotide. It is again particularly preferred that there is only one methylatable position in the section between the oligonucleotide probes which is filled in by the primer extension.
  • An oligonucleotide probe with a known sequence of n nucleotides is therefore extended with a heat-resistant polymerase by at most the number of nucleotides that lie between the 3 'end of the first oligonucleotide probe and the 5' end of the second hybridized oligonucleotide probe.
  • At least one nucleotide preferably carries a detectable label. This detectable label can in turn particularly preferably interact with a further label which is bound to one of the oligonucleotide probes, so that the extent to which the labeled nukeotide is incorporated can be measured. This interaction is particularly preferred fluorescence resonance energy transfer (FRET).
  • FRET fluorescence resonance energy transfer
  • either the first oligonucleotide probe and / or the second oligonucleotide probe bears a detectable label.
  • the type of extension preferably depends on the methylation status of at least one cytosine in the genomic DNA sample, or on any SNPs, point mutations or deletions, insertions and inversions that are present.
  • the nucleotides used are terminating and / or chain-extending nucleotides.
  • the terminating nucleotide is preferably a 2 ', 3' dideoxynucleotide and the chain-extending nucleotide is a 2 'deoxynucleotide. It is particularly preferred to incorporate a terminating nucleotide which also does not permit subsequent ligation if the methylation status typical of the background DNA was present in the respective template strand before the treatment in accordance with step 1 of the method.
  • a chain-extending nucleotide is incorporated if the methylation status typical of the DNA to be examined was present in the respective template strand before the treatment in accordance with step 1 of the method.
  • Nucleotides used but only a maximum of three nucleotides de, particularly preferably either the nucleotides dATP, dCTP and dTTP or the nucleotides dATP, dGTP and dTTP.
  • dUTP can be used instead of dTTP.
  • FIG. 3 A sequence example for the use of only three nucleotides is shown in FIG. 3.
  • At least one of the oligonucleotides is particularly preferably modified such that it cannot be extended by the polymerase at the 3 'end.
  • the 3 'end is particularly preferably functionalized with a phosphate group or 2' -3 'dideoxy modified.
  • the polymerase used has no or only a very low 5'-exonuclease activity.
  • the Stoffel fragment of Taq polymerase is therefore particularly preferably used.
  • At least one blocker oligonucleotide is used in addition to the oligonucleotide probes.
  • This blocker oligonucleotide preferably binds to the background DNA and hinders the ligase reaction and / or primer extension in the case of an additional polymerase step.
  • a blocker oligonucleotide binds to positions which are also covered by one of the oligonucleotide probes.
  • a blocker oligonucleotide binds to positions which are partially covered by the first oligonucleotide probe and partially by the second oligonucleotide probe.
  • a blocker oligonucleotide binds among other things at the position at which a ligation of the hybridized probe oligonucleotides could otherwise take place.
  • blocker oligonucleotides bind to the positions between the two hybridized oligonucleotide probes, which could otherwise be filled in by extending the first probe by means of a polymerase reaction.
  • blocker oligonucleotides When using blocker oligonucleotides, it is particularly preferred that they are present in such a modified manner that they cannot be extended by the polymerase at the 3 'end.
  • the 3 'end is particularly preferably functionalized with a phosphate group or 2' -3'-dideoxy-modified.
  • PNA peptide nucleic acids
  • other nucleic acid analogs as blocker molecules is also particularly preferred.
  • the blockers cannot be substantially degraded by the 5 'exonuclease activity of a polymerase that may be used.
  • the 5 'ends of the blockers can be modified or, particularly preferably, one or more phosphorothioate bridges can be present towards the 5' ends of the block oligonucleotide.
  • the probe oligonucleotides are particularly preferably phosphorylated prior to their use in the MLA or are phosphorylated directly by conventional oligonucleotide synthesis at the 5 'end. Phosphorylation of the probes is particularly preferably carried out using polynucleotide kinase and ATP. Phosphorylation is only required for the second oligonucleotide probe.
  • a method for the detection of cytosine methylation in DNA samples is particularly preferred, in which the following steps are carried out: 1. A genomic DNA sample is treated in such a way that the unmethylated cytosine bases are converted into uracil while the 5- Methylcytosine bases remain unchanged,
  • the chemically treated DNA sample is amplified using at least 2 pairs of essentially complementary probe oligonucleotides and a ligase, and
  • the sample DNA is obtained from serum or other body fluids of an individual. It is also preferred that the sample DNA from cell lines, blood, sputum, stool, urine, serum, brain spinal cord fluid, tissue embedded in paraffin, for example tissue from the eyes, intestine, kidney, brain, heart, prostate, lung , Breast or liver, histological slides and all possible combinations thereof.
  • a Taqman assay is particularly preferably carried out for the analysis. It is also preferred to perform a LightCycler assay (as described above).
  • the oligonucleotides used in addition to the primers particularly preferably do not have a 3 ′ OH function.
  • the reporter oligonucleotides particularly preferably carry at least one fluorescent label.
  • the reporter molecules indicate the amplification either by an increase or a decrease in the fluorescence and that the increase or decrease in the fluorescence is also used directly for analysis and a methylation state of the DNA to be analyzed is inferred from the fluorescence signal.
  • a method in which the further analysis is carried out by measuring the length of the amplified DNA to be examined is also particularly preferred, methods for measuring the length comprising gel electrophoresis, capillary gel electrophoresis, chromatography (e.g. HPLC), mass spectrometry and other suitable methods.
  • a method in which the further analysis is carried out by sequencing is also particularly preferred, methods for sequencing comprising the Sanger method, Maxam-Gilbert method and other methods such as Sequencing by Hybridization (SBH).
  • SBH Sequencing by Hybridization
  • a method is preferred in which the sequencing (according to Sanger) is carried out for each or a small group of CpG positions, each with a separate primer oligonucleotide and the extension of the primers is only one or a few bases, and from the type of primer extension to the Methylation congestion of the relevant positions in the DNA to be examined is closed.
  • the degree of methylation at the various examined CpG positions is used to infer the presence of a disease or another medical condition of the patient.
  • the amplificates themselves are also particularly preferably provided with a detectable label for the detection.
  • These labels are preferably fluorescent labels, radionuclides or removable mass labels, which are detected in a mass spectrometer.
  • a method variant is also preferred, the amplificates being detected overall in the mass spectrometer and thus being uniquely characterized by their mass.
  • Another object of the present invention is the use of one of the methods described for the diagnosis and / or prognosis of adverse events for patients or individuals, these adverse events belonging to at least one of the following categories: adverse drug effects; Cancers; CNS malfunction, damage or illness; Symptoms of aggression or behavioral disorders; clinical, psychological and social consequences of brain damage; psychotic disorders and personality disorders; Dementia and / or associated syndromes; cardiovascular disease, malfunction and damage; Malfunction
  • Damage or disease of the gastrointestinal tract Malfunction, damage or disease of the respiratory system; Injury, inflammation, infection, immunity and / or convalescence; Malfunction, damage or illness of the body as a deviation in the development process; Skin malfunction, damage or disease, the muscles, connective tissue or bones; endocrine and metabolic dysfunction, injury or illness; Headache or sexual malfunction.
  • methylated DNA human genomic DNA was treated with S-adenosyl methion and the CpG methylase (Sssl, New England Biolabs) according to the manufacturer's instructions.
  • S-adenosyl methion and the CpG methylase (Sssl, New England Biolabs) according to the manufacturer's instructions.
  • the preparation of unmethylated DNA as a reference was not necessary for the following examples, since the positions in question are consistently unmethylated in commercially available human DNA (Promega).
  • the bisulfite treatment was carried out according to the published agarose method (Olek A, Oswald J, Walter J. A modified and improved method for bisulphate based cytosine methylation analysis. Nucleic Acids Res. 1996 DEC
  • Methylated and untreated DNA was used in equal amounts (approx. 700 ng) in two different bisulfite reactions, but carried out analogously.
  • the probe oligonucleotides GGCGTTTTTTTGCGG (SEQ-ID.2) and TCGACGTTCGGGGT (SEQ-ID: 3) as well as the complementary probe oligonucleotides CCGCAAAAAAACGCC (SEQ-ID: 4) and ACCCCGAACGTCGA (SEQ-ID.5) were used, whereby the 3 and SEQ-ID: 4 were previously phosphorylated at the 5 'end by means of polynucleotide kinase. Conditions as described in WO 94/08047 (40 cycles) were used for the ligation.
  • the ligation products were detected using polyacrylamide gel electrophoresis.
  • the MLA reaction is shown schematically in FIG. 1. After treatment with bisulfite, the DNA is single-stranded (1) and allows one of the appropriate ones
  • Hybridization conditions the hybridization of the probes when the CG positions were methylated before the bisulfite reaction (2).
  • the probe oligonucleotides are ligated (3).
  • the double strand formed is now denatured in the next step, so that the ligated probes can in turn also serve as a template (4).
  • the complementary probe oligonucleotides (5) hybridize to this and a new ligation takes place (6). After denaturing, the complementary single strand is again available as a template and steps (2) to (7) can be repeated several times until sufficient ligation product has been formed.
  • Example 3 Example 3:
  • a blocker for the background DNA as described above can also be used. If the experiment is carried out analogously to Example 2, TGTGGTTGATGTTTG (SEQ ID: 6) can be used as a blocker. This block preferably binds when the background DNA was completely unmethylated in this area. Under these conditions it is possible to detect methylated templates at a ratio of 1: 100 to 1: 1000 depending on the total DNA concentration, without risking false positive results for the completely unmethylated control DNA.
  • FIG. 1 The use of a blocker oligonucleotide is shown in FIG. The same binds to the template DNA (1) and prevents the hybridization of the oligonucleotide probes. This means that only the template strand is retained after dehybridization; ligation does not take place.
  • the blocker oligonucleotide cannot hybridize.
  • the hybridization of the probe oligonucleotides and their ligation are essentially unimpeded (2a).
  • a ligation product is formed (3a).
  • the sequence GGGCGTTTTTTTGCGGTCGACGTTCGGGGTGTA (SEQ ID: 1) (after bisulfite treatment) was examined. This se- The result is when the methylation positions in question were methylated in the DNA sample.
  • the Sssl and bisulfite treated DNA sample of Example 1 was used.
  • the ligation products were again detected by means of polyacrylamide gel electrophoresis.
  • dGTP dGTP
  • dCTP ddATP
  • ligation can no longer take place.
  • the ligase / polymerase reaction is shown schematically in FIG. 3.
  • the DNA is single-stranded (1) and allows the probes to hybridize under the appropriate hybridization conditions if the CG positions were methylated before the bisulfite reaction (2).
  • the gap between the probes is filled in a polymerase reaction and subsequently the probes are ligated (3).
  • the double strand formed is now denatured in the next step, so that the ligated probes can in turn also serve as a template (4).
  • the complementary probe oligonucleotides (5) hybridize to this and a new ligation takes place (6).
  • the complementary single strand is again available as a template and steps (2) to (7) can be repeated several times until sufficient ligation product has been formed.

Abstract

Procédé de détection de la méthylation de la cytosine dans des échantillons d'ADN, qui consiste d'abord à traiter chimiquement un échantillon d'ADN génomique comportant de l'ADN à étudier et de l'ADN de fond de manière telle que toutes les bases cytosine non méthylées sont transformées en uracile, tandis que les bases 5-méthylcytosine restent inchangées. Ensuite, l'échantillon d'ADN traité chimiquement est amplifié à l'aide d'au moins deux amorces oligonucléotidiques et d'une polymérase. L'ADN à étudier est préféré en tant que matrice à l'ADN de fond. Dans l'étape finale, les produits d'amplification sont analysés et l'état de méthylation de l'ADN à étudier est déduit à partir de la présence d'un produit d'amplification et / ou à partir de l'analyse d'autres positions.
EP03704206A 2002-01-08 2003-01-08 Procede de detection de modeles de methylation de la cytosine par ligation exponentielle d'oligonucleotides sondes hybrides (mla) Ceased EP1463841A2 (fr)

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DE10201138A DE10201138B4 (de) 2002-01-08 2002-01-08 Verfahren zum Nachweis von Cytosin-Methylierungsmustern durch exponentielle Ligation hybridisierter Sondenoligonukleotide (MLA)
DE10201138 2002-01-08
PCT/DE2003/000073 WO2003057909A2 (fr) 2002-01-08 2003-01-08 Procede de detection de modeles de methylation de la cytosine par ligation exponentielle d'oligonucleotides sondes hybrides (mla)

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Families Citing this family (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19951189C2 (de) * 1999-10-15 2003-11-06 Epigenomics Ag Verfahren zur Unterscheidung von 5-Position-Methylierungsänderungen von Cytosin-Basen und Cytosin-zu-Thymin-Mutationen und zum Nachweis von single nucleotide polymorphisms (SNPs) oder Punktmutation in genomischer DNA
US20110151438A9 (en) 2001-11-19 2011-06-23 Affymetrix, Inc. Methods of Analysis of Methylation
DE10236406C1 (de) * 2002-08-02 2003-12-24 Epigenomics Ag Verfahren zur Amplifikation von Nukleinsäuren mit geringer Komplexität
WO2004050839A2 (fr) * 2002-11-27 2004-06-17 Sequenom, Inc. Procedes et systemes de detection et d'analyse de variations de sequences bases sur la fragmentation
US20050009053A1 (en) * 2003-04-25 2005-01-13 Sebastian Boecker Fragmentation-based methods and systems for de novo sequencing
US9394565B2 (en) 2003-09-05 2016-07-19 Agena Bioscience, Inc. Allele-specific sequence variation analysis
US7608394B2 (en) * 2004-03-26 2009-10-27 Sequenom, Inc. Methods and compositions for phenotype identification based on nucleic acid methylation
US9249456B2 (en) 2004-03-26 2016-02-02 Agena Bioscience, Inc. Base specific cleavage of methylation-specific amplification products in combination with mass analysis
US20080070240A2 (en) * 2004-04-08 2008-03-20 Toyo Boseki Kabushiki Kaisha Composition for deaminating dna and method of detecting methylated dna
US7364855B2 (en) 2004-04-30 2008-04-29 Applera Corporation Methods and kits for methylation detection
US20060073501A1 (en) * 2004-09-10 2006-04-06 Van Den Boom Dirk J Methods for long-range sequence analysis of nucleic acids
US20070087360A1 (en) * 2005-06-20 2007-04-19 Boyd Victoria L Methods and compositions for detecting nucleotides
US20060292585A1 (en) * 2005-06-24 2006-12-28 Affymetrix, Inc. Analysis of methylation using nucleic acid arrays
WO2007101075A2 (fr) * 2006-02-22 2007-09-07 Applera Corporation Procédé de double-ligature pour détecter le polymorphisme haplotype et grande échelle
US7820385B2 (en) * 2006-03-22 2010-10-26 The United States Of America As Represented By The Department Of Health And Human Services, Centers For Disease Control And Prevention Method for retaining methylation pattern in globally amplified DNA
US7901882B2 (en) * 2006-03-31 2011-03-08 Affymetrix, Inc. Analysis of methylation using nucleic acid arrays
US8206927B2 (en) 2007-01-23 2012-06-26 Sequenom, Inc. Method for accurate assessment of DNA quality after bisulfite treatment
US20080213870A1 (en) * 2007-03-01 2008-09-04 Sean Wuxiong Cao Methods for obtaining modified DNA from a biological specimen
WO2009114543A2 (fr) * 2008-03-11 2009-09-17 Sequenom, Inc. Tests adn pour déterminer le sexe d'un bébé avant sa naissance
US20110143959A1 (en) * 2008-08-13 2011-06-16 Rosetta Genomics Ltd. Compositions and methods for determining the prognosis of bladder urothelial cancer
US8476013B2 (en) * 2008-09-16 2013-07-02 Sequenom, Inc. Processes and compositions for methylation-based acid enrichment of fetal nucleic acid from a maternal sample useful for non-invasive prenatal diagnoses
US8962247B2 (en) 2008-09-16 2015-02-24 Sequenom, Inc. Processes and compositions for methylation-based enrichment of fetal nucleic acid from a maternal sample useful for non invasive prenatal diagnoses
US9624530B2 (en) 2009-08-03 2017-04-18 Epigenomics Ag Methods for preservation of genomic DNA sequence complexity
US20110104695A1 (en) 2009-11-05 2011-05-05 Epigenomics Ag Methods of predicting therapeutic efficacy of cancer therapy
DK2516680T3 (en) 2009-12-22 2016-05-02 Sequenom Inc Method and kits to identify aneuploidy
WO2012149339A2 (fr) 2011-04-29 2012-11-01 Sequenom, Inc. Quantification d'une minorité d'espèces d'acide nucléique
US9605313B2 (en) 2012-03-02 2017-03-28 Sequenom, Inc. Methods and processes for non-invasive assessment of genetic variations
US9920361B2 (en) 2012-05-21 2018-03-20 Sequenom, Inc. Methods and compositions for analyzing nucleic acid
WO2014011928A1 (fr) 2012-07-13 2014-01-16 Sequenom, Inc. Procédés et compositions pour l'enrichissement basé sur la méthylation d'un échantillon maternel en acide nucléique fœtal, utiles pour les diagnostics prénatals non invasifs
US10706957B2 (en) 2012-09-20 2020-07-07 The Chinese University Of Hong Kong Non-invasive determination of methylome of tumor from plasma
US9732390B2 (en) 2012-09-20 2017-08-15 The Chinese University Of Hong Kong Non-invasive determination of methylome of fetus or tumor from plasma
US10550426B2 (en) 2013-03-07 2020-02-04 Sekisui Medical Co., Ltd. Method for detecting methylated DNA
EP3597774A1 (fr) 2013-03-13 2020-01-22 Sequenom, Inc. Amorces pour analyse de la méthylation de l'adn
EP3117011B1 (fr) 2014-03-13 2020-05-06 Sequenom, Inc. Méthodes et procédés d'évaluation non invasive de variations génétiques
EP4130289A4 (fr) 2020-03-25 2023-09-13 FUJIFILM Corporation Procédé et programme pour calculer des niveaux de méthylation de base

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5494810A (en) * 1990-05-03 1996-02-27 Cornell Research Foundation, Inc. Thermostable ligase-mediated DNA amplifications system for the detection of genetic disease
US6017704A (en) * 1996-06-03 2000-01-25 The Johns Hopkins University School Of Medicine Method of detection of methylated nucleic acid using agents which modify unmethylated cytosine and distinguishing modified methylated and non-methylated nucleic acids
US5866336A (en) * 1996-07-16 1999-02-02 Oncor, Inc. Nucleic acid amplification oligonucleotides with molecular energy transfer labels and methods based thereon
DE19754482A1 (de) * 1997-11-27 1999-07-01 Epigenomics Gmbh Verfahren zur Herstellung komplexer DNA-Methylierungs-Fingerabdrücke
US6531302B1 (en) * 1999-04-12 2003-03-11 Nanogen/Becton Dickinson Partnership Anchored strand displacement amplification on an electronically addressable microchip
DE10010281B4 (de) * 2000-02-25 2005-03-10 Epigenomics Ag Ligase/Polymerase-Verfahren zur Detektion von Cytosin-Methylierung in DNA Proben
DE10029915B4 (de) * 2000-06-19 2005-06-16 Epigenomics Ag Verfahren zum Nachweis von Cytosin-Methylierungen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO03057909A2 *

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WO2003057909A3 (fr) 2003-10-16
JP2005514035A (ja) 2005-05-19
DE10201138A1 (de) 2003-07-17
DE10201138B4 (de) 2005-03-10

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