CN101255472B - Reagent case for detecting 946G >T mutation of large vestibular aqueduct related gene SLC26A4 - Google Patents

Abstract

The invention relates to a detection method, by which occurrence and type of vestibular aqueduct enlargement of individuals under test are diagnosed by detecting whether SLC26A4 genetic mutation exists in a specimen from individuals under test, wherein the SLC26A4 genetic mutation is a 946G>T heterozygous mutation located at SLC26A4 exon 8. The invention also relates to a detection kit for detecting whether SLC26A4 genetic mutation exists in a specimen from individuals under test, and the application of SLC26A4 genetic mutation to diagnosis and/or therapy of diseases related to vestibular aqueduct enlargement. The genetic mutation and detection method are helpful to clinical screen of SLC26A4 genetic mutation of deafness patients, and provide service for diagnosis and therapy of the deafness patients.

Description

Detect the test kit of 946G＞T sudden change of large vestibular aqueduct related gene SLC26A4

The application is dividing an application of Chinese patent application CN200510087749.5.

Technical field

The present invention relates to be used to detect the test kit of SLC26A4 mutator gene.

Background technology

The SLC26A4 gene is positioned at 7q31, it is by location such as Everett at first, and find that this transgenation can cause a kind of recessive hereditary disease: Pendred syndrome, clinical manifestation is a thyrocele, and merges the phonosensitive nerve deafness of aquaductus vestibuli expansion or Mondini deformity (aquaductus vestibuli enlarges merging cochlea underdevelopment).Afterwards, Usami etc. show the examination result that the simple aquaductus vestibuli of 6 examples enlarges the SLC26A4 gene of family, the sudden change of this gene can also cause simple aquaductus vestibuli to enlarge, its hereditary pattern also is a recessive inheritance. this shows that the SLC26A4 transgenation can cause aquaductus vestibuli to enlarge---and simple property aquaductus vestibuli enlarges or merges cochlea odd-shaped aquaductus vestibuli and enlarges.It is the modal deformity of inner ear that aquaductus vestibuli enlarges, and it accounts for 1～8% in hereditary hearing impairment.Mainly showing as high frequency hearing loss clinically is main phonosensitive nerve deafness, and the deafness multilist now is that severe or utmost point severe are deaf.Morbidity is many in the Childhood, and its premorbid often has flu, fever, wound etc. to make the inducement of intracranial hypertension.

Enlarge relevant SLC26A4 gene mRNA total length 4930bp with aquaductus vestibuli, contain 21 exons, open reading frame 2343bp runs through exon 2 and exon 21.The albumen of this genes encoding---Pendrin is that a molecular weight is 86kD, contains 780 amino acid whose transmembrane proteins, belongs to ion transport Zijia family.Scott and Bidart etc. discover, Pendrin mainly is expressed in the teleblem of thyroid follicular cells and the chief cell of ductus endolymphaticus and endolymphytic sac, the transhipment of mediation iodide ion and chlorion plays a role keeping on parathyroid tissue and the endolymphatic ionic equilibrium.At Tiroidina, when the Pendrin dysfunction, it can not in time be transported to the folliculus colloid to iodide ion, makes iodide ion in the follicular cells inner accumulated, thereby can not effectively organise and combine, thereby cause generation strumous in the Pendred syndrome with thyroglobulin.Qvortrup etc. think, the similar thyroid follicle of the endolymphytic sac of rat has balance gelatinoid filling blister cavities, and the function class of endolymphytic sac chief cell is similar to thyroid follicular cells, can synthesize, secretion, absorption, digesting protein.The chlorion transit barrier changes the composition of endolymph fluid, thereby the damage sensory epithelial cell causes phonosensitive nerve deafness.And because the toxic mechanism that osmotic pressure changes and composition changes causes the membranous labyrinth structural modification.Because just stasi when ductus endolymphaticus and endolymphytic sac to 4 year old, so their expansion can cause the change of surrounding bone structure, for example change of aquaductus vestibuli or cochlea structure.

Enlarge the examination of patient SLC26A4 transgenation for aquaductus vestibuli, abroad extensively carry out, the pathogenic mutation site of report surpasses 100, comprises missense mutation, the sudden change of frameing shift, nonsense mutation and splice site sudden change, is distributed in each exon.The SLC26A4 gene has tangible heterogeneity, and not agnate its mutant form is incomplete same.Its encoded protein can not accurately navigate on the cytolemma after this transgenation, but is present in endoplasmic reticulum or the golgi body, influences ion transport.

Aquaductus vestibuli enlarges the discovery of patient SLC26A4 transgenation, not only can promote the development of the fundamental researchs such as pathogeny that this is sick, also will promote the gene diagnosis of aquaductus vestibuli expansion and carrying out of treatment greatly.General examination by antenatal diagnosis examination and newborn infant SLC26A4 transgenation, can reduce the natality that aquaductus vestibuli enlarges infant, and realize diagnosing before the disease, thereby instruct the behavior of the infant that carries Disease-causing gene, prophylactic generation, the quantity that this will significantly reduce deafness patient alleviates social pressures.Following research will be devoted to the gene therapy aspect, can predict, and gene therapy brings qualitative leap will for the treatment that comprises deaf various heredopathias.

Summary of the invention

The object of the present invention is to provide and be used to detect the test kit that whether has the SLC26A4 transgenation from the sample of individuality to be measured.

According to an aspect of the present invention, the invention provides detection method a kind of and aquaductus vestibuli expansion disease related gene.This detection method is by detecting from whether there being the SLC26A4 transgenation in the sample of individuality to be measured, and diagnose aquaductus vestibuli in this individuality to be measured to enlarge the generation and the type of disease, wherein said SLC26A4 transgenation is the 349delC heterozygous mutant that is positioned at SLC26A4 gene extron 4, be positioned at the 916_917insG heterozygous mutant of SLC26A4 gene extron 7, be positioned at the 230A＞T heterozygous mutant of SLC26A4 gene extron 3, be positioned at the 1673A＞T heterozygous mutant of SLC26A4 gene extron 15, be positioned at the 1336C＞T heterozygous mutant of SLC26A4 gene extron 11, be positioned at the 1594A＞C heterozygous mutant of SLC26A4 gene extron 14, be positioned at the 1343C＞A heterozygous mutant of SLC26A4 gene extron 12, be positioned at the 1318A＞T heterozygous mutant of SLC26A4 gene extron 11, be positioned at the 946G＞T heterozygous mutant of SLC26A4 gene extron 8, be positioned at the 1975G＞C heterozygous mutant of SLC26A4 gene extron 17 or be positioned at the 626G of SLC26A4 gene extron 6＞A sudden change.

Described detection method can comprise the steps:

1) blood, body fluid or the tissue samples of collection individuality to be measured extract DNA;

2) be template with this DNA, carry out the PCR reaction, obtain the PCR reaction product with PCR primer at described each the mutational site design of SLC26A4 gene;

3) the PCR product that obtains is carried out direct sequencing analysis, the sequence of resulting sequence and SLC26A4 normal gene is compared, determine whether to exist the described mutational site of SLC26A4 gene;

4) judge that according to above result the aquaductus vestibuli whether individuality to be measured causes for the SLC26A4 transgenation enlarges.

Described detection method can further comprise the steps:

5) translate to determine whether to exist following amino acid mutation site by the normal reading frame: X125, X329, K77I, N558I, Q446X, S532R, S448X, K440X, G316X, V659L or G209E.

Below, specify detection method about SLC26A4 gene 946G＞T heterozygous mutant:

The SLC26A4 gene of control group member by family member that 70 routine aquaductus vestibulis are enlarged and 80 normal good hearings carries out examination, finds an aquaductus vestibuli expansion patient have the new mutational site of SLC26A4 gene (946G＞T, G316X).This sudden change causes the translation premature termination of Pendrin in the 316th amino acids, lacks 465 amino acid than normal aminoacid sequence.All do not find this sudden change in 80 normal controls, it is closely related to illustrate that this mutational site and aquaductus vestibuli enlarge.Fig. 1 provides the contrast figure of SLC26A4 coding region amino acid and nucleic acid base, and with red fluorescence the position, mutational site is shown, and ends at 316 from amino acid whose coding.

In a specific embodiment of the present invention, detect the method that whether has SLC26A4 gene 946G＞T heterozygous mutant in the sample of individuality to be measured, comprise the steps:

12.1) gather blood, body fluid or the tissue samples of individuality to be measured, extract DNA;

12.2) be template with this DNA, carry out the PCR reaction with following PCR primer, obtain the PCR reaction product;

PDS8-F：5’-AAGTTCAGCATTATTTGGTTGACA-3’

PDS8-R：5’-TGGTTGTTTCTTCCAGATCACA-3’

12.3) the PCR reaction product that obtains is directly checked order, and the sequence of sequencing result and SLC26A4 normal gene is compared, determine whether to exist the 946G＞T mutational site of SLC26A4 gene; Or

12.4) adopt Nde I restriction enzyme to carry out endonuclease reaction the PCR reaction product that obtains, agarose electrophoresis detects, and determines whether to have 946G＞T mutational site;

12.5) judge according to above result whether this individuality to be measured exists SLC26A4 gene 946G＞T sudden change.

In another embodiment of the invention, adopt the endonuclease reaction of Nde I restriction enzyme to detect mutator gene, after above-mentioned steps 12.2 resulting PCR reaction product are carried out endonuclease reaction with Nde I, agarose electrophoresis detects, normal gene can be cut by Nde I, and mutator gene can not be cut by Nde I enzyme, determines whether to exist the mutational site thus; Judge according to detected result whether individuality to be measured is that the aquaductus vestibuli that SLC26A4 gene 946G＞the T sudden change causes enlarges (Fig. 6).

In above-mentioned detection method at each mutational site of SLC26A4 gene, resulting PCR reaction product can also detect with hybridization probe, used hybridization probe can be and normal SLC26A4 nucleotide sequence hybridization, or with the nucleotide sequence hybridization of sudden change, or with their probe of complementary sequence hybridization.These probes can be used radio isotope, chromonic material or fluorescent substance mark, especially can utilize the allele specific probe, whether have the sudden change that has been determined with examination.

According to a further aspect in the invention, the invention provides and be used to detect the test kit that whether has the SLC26A4 transgenation from the sample of individuality to be measured, can comprise one or more combination of following several reagent in the test kit:

From testing sample, extract the reagent of DNA;

The PCR primer and the corresponding PCR reaction reagent that are used for the following mutational site of amplified sample DNA SLC26A4 gene:

Be positioned at the 349delC heterozygous mutant of SLC26A4 gene extron 4, be positioned at the 916_917insG heterozygous mutant of SLC26A4 gene extron 7, be positioned at the 230A＞T heterozygous mutant of SLC26A4 gene extron 3, be positioned at the 1673A＞T heterozygous mutant of SLC26A4 gene extron 15, be positioned at the 1336C＞T heterozygous mutant of SLC26A4 gene extron 11, be positioned at the 1594A＞C heterozygous mutant of SLC26A4 gene extron 14, be positioned at the 1343C＞A heterozygous mutant of SLC26A4 gene extron 12, be positioned at the 1318A＞T heterozygous mutant of SLC26A4 gene extron 11, be positioned at the 946G＞T heterozygous mutant of SLC26A4 gene extron 8, be positioned at the 1975G＞C heterozygous mutant of SLC26A4 gene extron 17 or be positioned at the 626G of SLC26A4 gene extron 6＞A sudden change;

Pcr amplification product is carried out the reagent of digestion with restriction enzyme reaction; And/or

The reagent that pcr amplification product is checked order.

For example, a test kit that detects the described sudden change of SLC26A4 gene is provided in one embodiment of the invention, be equipped with in the container in order to detect the composition of the described sudden change of SLC26A4 gene, what provide simultaneously with it can be through manufacturing, use and the marketing information of the audit of medication management mechanism of government, relevant medicine or biological products.For example, after adopting pcr amplification, the direct test kit in the described mutational site of SLC26A4 gene in the test sample can contain amplimer, dNTP, be used for one or more of the archaeal dna polymerase of PCR reaction and damping fluid, endonuclease reaction and/or the required reagent of sequencing reaction etc.It is known to those skilled in the art that above component only is that schematically for example, described primer can adopt above-mentioned a pair of PDS-F and PDS-R primer, the archaeal dna polymerase of the described PCR of being used for reaction is the enzyme that can be used in pcr amplification.

The using method of described test kit mainly comprises the steps:

(1) DNA of extraction blood sample to be measured utilizes above-mentioned a pair of PDS-F and PDS-R primer, carries out pcr amplification reaction;

(2) the endonuclease reaction detection that suddenlys change; And/or

(3) directly order-checking behind the PCR reaction product purifying is with the sequence of gained and the existence in the relatively more definite mutational site of the standard sequence among the Genbank;

(4) translate to determine whether to exist described amino acid mutation site by the normal reading frame.

This test kit can detect the described mutational site of SLC26A4 gene quickly and easily, thereby is applied to sudden change detection and diagnoses and treatment thereof that aquaductus vestibuli enlarges case.

In accordance with a further aspect of the present invention, the invention provides the application of SLC26A4 mutator gene in diagnosis and/or the expansion of treatment aquaductus vestibuli, by detecting deaf occurrence cause and the type of judging this patient from the described sudden change that whether has the SLC26A4 gene in patient's the sample to be tested, and then provide reference for clinical diagnosis and treatment; In addition; aspect further clinical treatment, detected result be the described sudden change of SLC26A4 gene has taken place after, normal gene can be imported the cell that carry mutator gene and express therein; it can be recombinated with the endogenous mutator gene, thereby can carry out gene therapy.

The present invention provides the described 11 kinds of sudden changes that have the SLC26A4 gene in Chinese population first, and illustrates that this mutator gene enlarges relevant with aquaductus vestibuli.Simultaneously, whether the present invention proposes by detecting exists the SLC26A4 transgenation to judge the deaf reason that takes place and the detection method of type among the patient, this will help carrying out clinically the SLC26A4 Mutation Screening work of deafness patient, for deafness patient provides diagnosis and treatment service.

Below in conjunction with accompanying drawing,, describe in detail but do not limit the present invention by explanation to better embodiment of the present invention.

Brief description of drawings

Fig. 1～6 are the accompanying drawing about SLC26A4 gene 946G＞T heterozygous mutant:

Fig. 1 is the contrast of SLC26A4 coding region amino acid and nucleic acid base: sudden change is positioned at the 946th base, corresponding to the 316th amino acid become the translation termination signal (the grey mark part be the sudden change base and amino acid), thereafter aminoacid sequence underscore mark, this section sequential amino acid deletion.

Fig. 2 is the structural representation of Pendrin, and asterisk illustrates the 316th amino acids position, the G316X sudden change takes place after, sequential amino acid deletion thereafter;

Fig. 3 shows temperature of reaction and time for PCR reaction process synoptic diagram in SLC26A4 gene 946G of the present invention＞T heterozygous mutant detection method;

Fig. 4 is in SLC26A4 gene 946G of the present invention＞T heterozygous mutant detection method, the PCR product carried out electrophoresis when quantitative, the synoptic diagram of the quantitative Marker in the agarose gel electrophoretogram;

Fig. 5 is the part sequencing result of the inventive method SLC26A4 gene extron 8, and the top is the normal control sequence, and the below is a mutant nucleotide sequence, the arrow indication be the mutational site (946G＞T, G316X);

Mutational site restriction enzyme digestion and electrophoresis figure in 946G in Fig. 6 the inventive method＞T heterozygous mutant detection method, among the figure from left to right: first swimming lane be molecular weight standard, second for the restriction enzyme mapping of normal gene, the 3rd swimming lane are the restriction enzyme mapping of heterozygous mutant gene,

Restriction enzyme Nde I can cut at 942 and 943 bit bases, and make normal people PCR product fragment be cut into 102bp and two fragments of 204bp by original 306bp, and this restriction enzyme site disappears after the sudden change, can not cut, because this organizes this example for heterozygous mutant, so be shown as 3 bands on the running gel figure;

The embodiment of invention

The used test materials of the present invention if no special instructions, is commercially available purchase product.

Research process of the present invention: collect aquaductus vestibuli by deaf sick outpatient service and enlarge the patient, under the voluntary prerequisite of patient and family members thereof, the 5-10ml blood sample left and taken in signature informed consent postscript, set up the patient medical history database, incidence and contact method in detail record conditions of patients, the family.Then, use phenol chloroform method for extracting extraction genomic dna, quantitatively put in storage the back ,-20 ℃ of preservations, and every part of DNA sample is all accurately corresponding to the patient clinical data of registering.Then, describe the design primer, comprise SLC26A4 gene coding region and flanking sequence thereof, carry out pcr amplification according to the document of Coyle etc.The PCR product is directly checked order: sequencing primer is identical with the pcr amplification primer, uses the ABI 3730DNA of company sequenator and carries out forward and reverse order-checking.The sequence and the standard sequence among the Genbank that obtain are compared, determine the SLC26A4 mutational site.At some mutational site of SLC26A4 gene, the PCR product is also optionally carried out endonuclease reaction: use specific restriction enzyme and normal people PCR product can be cut into two fragments, and after sudden change occurring, restriction enzyme site disappears, and can not cut.Translate to determine the mutational site of SLC26A4 gene by the normal reading frame.

The detection of SLC26A4 gene 349delC heterozygous mutant

The patient who enlarges with aquaductus vestibuli is as research object, by examination to each exon of coding region of the SLC26A4 gene of 70 example these patient and his family set members and 85 routine normal controls, find aquaductus vestibuli enlarge the patient on exon 4, have the new mutational site of SLC26A4 gene (349delC, X125).This patient is a compound heterozygote, meets the pattern of autosomal recessive inheritance, and there is another sudden change in the allelotrope of its SLC26A4.Mother of patient is the carrier of 349delC (X125) sudden change.This mutational site all is not found in 70 control groups, illustrate this mutational site and aquaductus vestibuli enlarge be divided into from.

The detection method of [embodiment 1] SLC26A4 gene 349delC heterozygous mutant

One, the preparation of object blood sample DNA to be measured

1, research object: patient's 70 examples that the aquaductus vestibuli that deaf sick outpatient service is collected enlarges, normal control 85 examples.To all its medical history of participator's probe and family history, and it is carried out a medical examination, the otology inspection comprises otoscopy, audiological evaluation.Everyone blood sample collection 5-10ml after the signature Informed Consent Form.

2, extracting genome DNA: adopt the phenol chloroform extraction method.

First day

1) anticoagulation is done 1 times of dilution with PBS.

2) the lymph parting liquid (18 ℃-28 ℃) of 2 times of volumes of adding in centrifuge tube is spread the blood that 1 times of volume of one deck has diluted, room temperature 1000 * g, centrifugal 20 minutes above.

3) supernatant is abandoned in suction, and karyocyte layer in the middle of the careful sucking-off changes in the 5mlEp pipe, and 5000 * g centrifugal 10 minutes, washes once with PBS then.5000 * g, centrifugal 10 minutes.

4) cell is suspended from the 2mlTE damping fluid, adds 10% SDS to final concentration 0.5% (100 μ l), protein kinase k 100-200 μ g/ml (10mg/ml), 50 ℃ water-bath 3-5 hour.

5) use the phenol chloroform extraction.With isopyknic saturated phenol, add mixing, 5000 * g, centrifugal 10 minutes.

6) suct clear liquid to new centrifuge tube, abandon lower sediment, add equal-volume phenol: chloroform mixture, mixing, 5000 * g, centrifugal 10 minutes.

7) suct clear liquid to new centrifuge tube, abandon lower sediment, add the equal-volume chloroform: iso pentane alcohol mixture, mixing, 5000 * g, centrifugal 10 minutes.

8) suct clear liquid to new centrifuge tube, abandon lower sediment, add the sodium acetate of 1/10 volume, mixing.

9) dehydrated alcohol of 2.5 times of volumes of adding.

10)-20 a ℃ deposit D NA spends the night.

Second day

11) high speed centrifugation, 10000 * g, 10 minutes, 4 ℃.

12) abandon supernatant, add 75% ethanol 2ml, high speed centrifugation 10000 * g, 5 minutes.

13) abandon supernatant, dry up.

14) with TE damping fluid dissolving (200 μ l TE/5ml whole bloods, 400 μ l TE/10ml whole bloods).

15) packing.1% agarose electrophoresis and spectrophotometer are quantitative.

Two, the pcr amplification of SLC26A4 gene extron 4

1, primer sequence

Upstream primer:

PDS4-F：5’-TAATCACTTTGCATGTGCTTT-3’(nt11480-nt11500)

Downstream primer:

PDS4-R：5’-GCCAAAACACTTTAAACATGA-3’(nt11648-11nt668)

Annotate: SLC26A4 gene order searching number: GeneID:5172

2, the foundation of PCR reaction system

The composition of the PCR reaction system of SLC26A4 gene sees Table 1.

The PCR reaction system of table 1 SLC26A4 gene

Title	Original liquid concentration	Application of sample amount (μ l)	The system final concentration
				Damping fluid	10×?	?2.5?	1×?
?dNTP?	2.5mM?	?2.0?	0.2mM?
				Primer	10μM?	?1?	0.4μM?
The Taq enzyme	5units/μl?	?0.5?	0.1units/μl?
				Template (DNA that extracts in the step 1)	100ng/μl?	?1?	4ng/μl?
The total reaction system	ddH 2O polishing to 25 μ l	?	?

Wherein damping fluid, dNTP, Taq enzyme are buied from precious biotech firm.Primer is given birth to worker company by Shanghai and is synthesized.Reaction conditions: PCR is reflected on ABI company 9700 thermal cyclers and carries out.

Three, the purifying of PCR product

1, in 96 orifice plates that the PCR product is housed, adds 50 μ l sterilized waters, mixing.

2, it is transferred in the Millipore purifying plate, be put on the vacuum pump suction filtration about 3 minutes, see in the purifying plate not having water to get final product.

3, the deionized water that adds 50 μ l in the purifying plate once more continues suction filtration, in the purifying plate, do not have water till.

4, the purifying plate is taken off from vacuum pump, in plate, add the deionized water of 20 μ l, static 15 minutes, shook again 15 minutes, be drawn onto then in new 96 orifice plates.

5, be kept in-20 ℃ of refrigerators.

Four, electrophoresis is quantitative

1, sample is prepared

PCR product (2 μ l)+sample-loading buffer (6 μ l) is totally 8 μ l * 96

Get one 96 hole point templates, every hole adds sample damping fluid 6 μ l earlier, and from the chamber plate that the PCR product is housed, PCR product (2 μ l) is shifted out with the volley of rifle fire in every hole, transfers on the point template, mixing, centrifugal (chamber plate hole number corresponding one by one with 96 hole point templates).

2, flow process

1) joins glue (1.0% agarose): take by weighing the 3.0g agarose, be suspended in (500ml Erlenmeyer flask) among 300ml 0.5 * TBE.

2) colloidal sol: high fire is heated to and boils in the microwave oven, and constantly boiling number minute is noted not boiling, and takes out mixing therebetween.

3) cool glue: treat that glue dissolves fully, from microwave oven, take out that cool to about 60 ℃, (about 10 μ l 10mg/ml), shake up to add 1 EB.

4) shop glue: obturage with adhesive plaster in dull and stereotyped two ends, the 250ml glue is all poured into flat board, inserts comb scale.

5) gluing: flat board is put in the electrophoresis chamber that fills electrophoresis liquid (0.5 * TBE, liquid level apart from glue face 1 to 2mm), pulled up comb scale.

6) application of sample:, add the DNA standard substance with single rifle at last with volley of rifle fire form application of sample in accordance with regulations.

7) walk glue: cover the electrophoresis chamber lid, check positive and negative level, open electrophoresis apparatus, regulate electrophoretic voltage.

8) quantitative: as to walk from well 1.5 to 2cm places when tetrabromophenol sulfonphthalein, close electrophoresis apparatus, carefully get glue, put into pickup camera and take a picture, carry out quantitatively.Quantitatively marker is DL 2000, through behind the electrophoresis, 6 bands is arranged as seen, and fragment length is respectively 2000bp, 1000bp, and 750bp, 500bp, 250bp, 100bp, the total concn of DL2000 is 300ng/5 μ l.Get 5ul DL2000 during electrophoresis, therefore the content of every band is 50ng.Get 3 μ l (PCR product)+5 μ l (sample-loading buffer) during PCR product electrophoresis and carry out electrophoresis.The content of relatively judging the PCR product according to the gray-scale value of gray-scale value behind the PCR product electrophoresis and DL2000.

Five, the direct order-checking of SLC26A4 gene PCR amplified production

1, the purity of PCR product D NA template and consumption requirement

DNA purity: OD260/OD280=1.6～2.0.

DNA concentration: PCR product 10ng/ μ L.

The DNA consumption:

The PCR product

100-200bp 1-3ng

200-500bp 3-10ng

500-1000bp 5-20ng

1000-2000bp 10-40ng

＞2000bp 40-100ng

2, sequencing reaction

(1) the required reagent of sequencing reaction should be fresh preparation, need can use after autoclaved reagent must be sterilized.The required equipment of sequencing reaction (first-class as 384 orifice plates, tip) should be cleaning sterile equally.

(2) in order to guarantee the fresh of sample and reaction reagent that check order, should be during application of sample in operation on ice.

(3) present reaction system is 5 μ l, and all ingredients add-on sees Table 2.

The sequencing reaction system of table 2 SLC26A4 gene PCR amplified production

Template	The PCR product of purifying (preparation among the embodiment 1)	200-500bp?	3-10ng?
				500-1000bp?	5-20ng?	?	?
1000-2000bp?	40-100ng?	?	?
				BigDye?v3.1 *	0.25μl?	?	?
5 * damping fluid (Tris-HCl pH9.0, MgCl 2)	0.875μl(Kit)?	?	?
				Primer	3.2pmol?	?	?
Mend to 5 μ l with sterilized water	?	?	?

^*A kind of fluorescence dye that is used for sequencing reaction that BigDye 3.1 produces for u.s.a. applied biosystem company (ABI).

(4) sample is put on the PCR instrument, and the process of the reaction of doing sees Table 3.

The sequencing reaction process of table 3 SLC26A4 gene PCR amplified production

Step	Effect
			1?	96℃，2min.?
2?	Repeat 30 circulations of following process: ● 96 ℃, 10sec; ● 50 ℃, 5sec; ● 60 ℃, 4min.
		3?	Remain on 4 ℃, up to purifying

(5) sample that has reacted will in time take off from the PCR instrument, and the sample that will carry out purifying in the short period of time is positioned in 4 ℃ of refrigerators, surpass more than one day could purifying sample to be positioned over-20 ℃ of refrigerators freezing.

3, the purifying of sequencing reaction thing and order-checking

(1) in every hole, adds 20 μ l, 80% ethanol, the centrifugal 30min of 4000rpm; Sample panel is placed on the paper handkerchief of rolling well, gets rid of in whizzer, speed can not surpass 1000rpm when getting rid of;

(2) in every hole, add 30 μ l, 70% ethanol, 4, the centrifugal 10min of 000rpm gets rid of;

(3) repeat the 2nd operation that goes on foot;

(4) repeat the 2nd operation that goes on foot;

(5) sample panel is put in the clean drawer the dry 30min of lucifuge;

(6) add 5 μ l methane amides, the envelope film is in the centrifugal being placed on-20 ℃ refrigerator;

(7) go up the preceding 95 ℃ of sex change of machine 5 minutes, placed 2 minutes on ice, sample is gone up in centrifugal back.

Six, the mutational site endonuclease reaction detects

The composition of endonuclease reaction system sees Table 4, and reaction conditions is 37 ℃ of water-baths 4 hours.Use 2% agarose gel electrophoresis and detect, method is quantitative referring to electrophoresis among the embodiment 1.

Restriction analysis is to have found a restriction enzyme Eco31I restriction enzyme site in this mutational site, when not undergoing mutation, restriction enzyme Eco31I can cut at 352 and 353 bit bases, and make PCR product fragment be cut into 72bp and two fragments of 117bp by original 189bp, and this restriction enzyme site disappears after the sudden change, can not cut.Because this patient is a heterozygous mutant, so be shown as 3 bands on the running gel figure.

Table 4 endonuclease reaction system

Reagent	Sample size
		Eco31I?	1μl?
10×L?Buffer?	2μl?
		The PCR product	6μl?
ddH 2O?	Up?to?20μl

Eco31I restriction enzyme and 10 * L Buffer purchase in precious biotech firm, and the PCR product is the pcr amplification product among the embodiment 1.

[embodiment 2] mutational site Study on Evolution

Mutation analysis: use the Seqman in DNAStar5.0 (Lasergene inc.) software package ^TMSoftware carries out the sequence comparative analysis.The standard sequence that sequence that order-checking is obtained and NCBI retrieve is compared, and finds out mutant nucleotide sequence, found the mutational site (349delC, X125).

Study on Evolution: 349delC sudden change is positioned at second of Pendrin and strides the film district, and it makes aminoacid sequence from 117 living frameing shift of starting, and back premature termination is in 125 amino acids.This sudden change must influence the 26S Proteasome Structure and Function of Pendrin.

The detection of SLC26A4 gene 946G＞T heterozygous mutant

The patient who enlarges with aquaductus vestibuli is as research object, by examination to each exon of coding region of the SLC26A4 gene of 70 example these patient and his family set members and 80 routine normal controls, find aquaductus vestibuli enlarge the patient on exon 8, have the new mutational site of SLC26A4 gene (946G＞T, G316X).This patient is a compound heterozygote, meets the pattern of autosomal recessive inheritance, and there is another sudden change in the allelotrope of its SLC26A4.This mutational site all is not found in 80 control groups, illustrate this mutational site and aquaductus vestibuli enlarge be divided into from.

The detection of [embodiment 3] SLC26A4 gene 946G＞T heterozygous mutant

Basic skills and step are referring to embodiment 1.Pcr amplification primer sequence at SLC26A4 gene extron 8:

Upstream primer:

PDS8-F：5’-AAGTTCAGCATTATTTGGTTGACA-3’(nt22743-nt22766)

Downstream primer:

PDS8-R：5’-TGGTTGTTTCTTCCAGATCACA-3’(nt23144-nt23167)

The PCR reaction process as shown in Figure 3; The PCR product is carried out the quantitative agarose gel electrophoretogram of electrophoresis see Fig. 4; Sequencer map is seen Fig. 5.

The mutational site endonuclease reaction detects

The composition of endonuclease reaction system sees Table 5, and reaction conditions is 37 ℃ of water-baths 2 hours.The application agarose electrophoresis detects, and method is quantitative referring to electrophoresis among the embodiment 1.The endonuclease reaction electrophorogram as shown in Figure 6.

Restriction analysis is to have found a restriction enzyme Nde I restriction enzyme site in this mutational site, when not undergoing mutation, restriction enzyme Nde I can be 942 and 943 incisions, PCR product fragment is cut into 102bp and two fragments of 204bp by original 306bp, and this restriction enzyme site disappears after the sudden change, can not cut.Because this example is a heterozygous mutant, so be shown as 3 bands on the running gel figure.

Table 5 endonuclease reaction system

Reagent	Sample size
		Nde?I?	1μl?
10×L?Buffer?	2μl?
		The PCR product	4μl?
ddH 2O?	Up?to?20μl

^*Nde I restriction enzyme and 10 * L Buffer purchase in precious biotinylated biomolecule Engineering Co., Ltd.

[embodiment 4] mutational site Study on Evolution

Mutation analysis: the SeqmanTM software of using in DNAStar5.0 (Lasergene inc.) software package carries out the sequence comparative analysis.The standard sequence that sequence that order-checking is obtained and NCBI retrieve is compared, and finds out mutant nucleotide sequence, found the mutational site (946G＞T, G316X).

Study on Evolution: 946G＞T sudden change causes that the aminoacid sequence premature termination that makes the SLC26A4 genes encoding in 316 amino acids, forms jejune Pendrin, and this change must cause that the 26S Proteasome Structure and Function of Pendrin is unusual.

Detect test kit and application thereof that aquaductus vestibuli enlarges relevant SLC26A4 transgenation

[embodiment 5]

The test kit that detects the SLC26A4 transgenation can be prepared into the independent test kit that detects each single mutational site as required, also can be prepared into the test kit that detects a plurality of or all SLC26A4 gene mutation sites, be that example describes with the test kit that detects mutational site of the present invention below:

1, test kit contains:

(1) amplification primers

1 pair of primer of aforementioned 946G＞T mutational site design, perhaps other spendable primers at this mutator gene design for detection SLC26A4 gene;

Annotate: SLC26A4 gene order searching number: GeneID:5172

Other reagent that is included in alternatively in the test kit comprises following reagent:

(2) pcr amplification Taq enzyme 5U/ μ l

(3) 10 * damping fluids (contain 15ml MgCl ₂)

(4)dNTP 2.5mM

(5) Eco31 I restriction enzyme; BseM I restriction enzyme; Hind III restriction enzyme; Nde I restriction enzyme; Or EcoR I restriction enzyme

(6)10×L?Buffer

(7)Big-Dye?mix

2, using method

Mainly comprise the steps:

1) pcr amplification

Gather the sample (blood, body fluid, tissue etc.) of individuality to be measured, extract DNA, carry out pcr amplification respectively with above-mentioned primer at each mutator gene;

2) PCR product purification

The MultiScreen-PCR plate that will contain the PCR product vacuumizes, and adds deionized water, leaves standstill, and the MultiScreen-PCR plate is placed on the mixing tank shake subsequently, is transferred in 96 orifice plates of another cleaning after the PCR product behind the purifying dissolves again;

3) endonuclease reaction

To carry out endonuclease reaction according to the endonuclease reaction system of embodiment 3 respectively at the amplified production in 946G＞T mutational site, judge whether to exist said mutation with reference to Fig. 6.

4) sequencing reaction and checking

The PCR product at each mutational site of above-mentioned amplification is carried out sequencing reaction with the PCR primer as sequencing primer, on the ABI9700 thermal cycler, carry out sequencing reaction.After reaction finished, extension products was splined on ABI PRISM 3730DNA sequenator.Resulting order-checking collection of illustrative plates is analyzed, relatively can be found the mutational site with the standard sequence among the Genbank;

5) translate to determine whether to exist corresponding amino acid mutation site by the normal reading frame.

Concrete grammar is referring to the detailed description among the embodiment of front.

Above detailed description of the present invention does not limit the present invention, and those skilled in the art can make various changes and distortion according to the present invention, only otherwise break away from spirit of the present invention, all should belong to the defined scope of claims of the present invention.

Claims (4)

1. detection and aquaductus vestibuli enlarge the test kit of the 946G that the is positioned at SLC26A4 gene extron 8＞T heterozygous mutant of disease-related, and described test kit comprises following reagent:

From testing sample, extract the reagent of DNA;

The PCR primer and the corresponding PCR reaction reagent that are used for the 946G＞T heterozygous mutant of amplified sample DNA SLC26A4 gene extron 8;

The reagent that pcr amplification product is checked order;

Wherein said PCR primer is:

PDS8-F：5’-AAGTTCAGCATTATTTGGTTGACA-3’

PDS8-R：5’-TGGTTGTTTCTTCCAGATCACA-3’。

2. test kit as claimed in claim 1, wherein said test kit further comprise the reagent that pcr amplification product is carried out the digestion with restriction enzyme reaction.

3. test kit according to claim 1, the step that described test kit is used to detect the 946G＞T heterozygous mutant that is positioned at SLC26A4 gene extron 8 comprises:

1) blood, body fluid or the tissue samples of collection individuality to be measured extract DNA;

2) be template with this DNA, carry out the PCR reaction, obtain the PCR reaction product with following PCR primer;

PDS8-F：5’-AAGTTCAGCATTATTTGGTTGACA-3’

PDS8-R：5’-TGGTTGTTTCTTCCAGATCACA-3’

3) the PCR reaction product that obtains is directly checked order, and the sequence of sequencing result and SLC26A4 normal gene is compared, determine the 946G＞T mutational site of SLC26A4 gene; Or

4) adopt Nde I restriction enzyme to carry out endonuclease reaction the PCR reaction product that obtains, agarose electrophoresis detects, and determines the 946G＞T mutational site of SLC26A4 gene.

4. as test kit as described in the claim 3, described step also further comprises:

5) translate to determine G316X amino acid mutation site according to the normal reading framework.

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