阅读说明：本技术 一种hla-b位点等位基因分型试剂盒及其检测方法 (HLA-B locus allele typing kit and detection method thereof ) 是由 何军 邱桥成 于 2020-07-31 设计创作，主要内容包括：本发明公开了一种HLA-B位点等位基因分型试剂盒及其检测方法,该试剂盒包括用于扩增覆盖HLA-B位点第2,3,4外显子区域的扩增引物,以及分别针对第2,3,4外显子区域的特异性测序引物。该检测方法通过扩增引物对DNA样本进行扩增,然后分别使用针对HLA-B位点第2,3,4外显子区域的测序引物对扩增产物中的第2,3,4外显子进行测序,将得到的测序结果与数据库比对得到HLA-B位点等位基因型。该方法可以使用扩增引物直接针对HLA-B位点进行扩增及使用测序引物第2,3,4外显子区域进行测序,获得B位点上各种等位基因型,避免了与其同源性极高的HLA-A,C位点基因序列的干扰,提高了分型结果的准确性。(The invention discloses an HLA-B locus allele typing kit and a detection method thereof, wherein the kit comprises an amplification primer for amplifying the 2 nd, 3 rd and 4 th exon regions covering the HLA-B locus and specific sequencing primers aiming at the 2 nd, 3 th and 4 th exon regions respectively. According to the detection method, an amplification primer is used for amplifying a DNA sample, sequencing primers aiming at exon regions 2,3 and 4 of an HLA-B locus are used for sequencing exons 2,3 and 4 in an amplification product respectively, and the obtained sequencing result is compared with a database to obtain the allele type of the HLA-B locus. According to the method, the amplification primers can be used for directly amplifying the HLA-B locus and sequencing the exon regions 2,3 and 4 of the sequencing primers to obtain various allelic genotypes on the B locus, so that the interference of the HLA-A and C locus gene sequences with extremely high homology with the B locus is avoided, and the accuracy of the typing result is improved.)

1. An HLA-B locus allele typing kit characterized by: comprises amplification primers for amplifying the 2 nd, 3 rd and 4 th exon regions covering the HLA-B locus and specific sequencing primers aiming at the 2 nd, 3 th and 4 th exon regions respectively;

the nucleotide sequence of the amplification primer is as follows:

an upstream primer BF: TCTCAGGGTCTCAGGGTCCG, as shown in SEQ ID NO. 1;

a downstream primer BR: CAGCCAGGCCAGCAACAATG, as shown in SEQ ID NO. 2;

sequencing primers for exon 2 were as follows:

upstream primer B2F: CCCAGGCTCCCACTCCAT, as shown in SEQ ID NO. 3;

the downstream primer B2R: GGGGAGTCGTGACCTGC, as shown in SEQ ID NO. 4;

sequencing primers for exon 3 were as follows:

upstream primer B3F: GGCCAGGGTCTCACA, as shown in SEQ ID NO. 5;

the downstream primer B3R: GGCGACATTCTAGCGC, as shown in SEQ ID NO. 6;

sequencing primers for exon 4 were as follows:

upstream primer B4F: AGATGCAAAGCGCCTGAA, as shown in SEQ ID NO. 7;

the downstream primer B4R: GGCTCCTGCTTTCCCTGA, as shown in SEQ ID NO. 8.

2. The HLA-B locus allele-typing kit according to claim 1, wherein: the amplification system covering the 2 nd, 3 rd and 4 th exon regions of the HLA-B site comprises: upstream primer BF, downstream primer BR, 10 XBuffer, dNTP, Taq enzyme and DNA sample.

3. The HLA-B locus allele-typing kit according to claim 1, wherein: the sequencing system for the 2 nd, 3 th and 4 th exon regions comprises: PCR amplification products, B2F/B2R, B3F/B3R, B4F/B4R sequencing primers and Bigdye.

4. A method for detecting an allelic type of HLA-B locus using the kit according to any one of claims 1 to 3, wherein: the method comprises the following steps:

(1) extracting DNA;

(2) amplifying the DNA sample extracted in the step (1) by using amplification sequences shown in SEQ ID NO. 1 and SEQ ID NO. 2 to obtain a DNA sequence covering HLA-B sites and containing exon regions 2,3 and 4;

(3) carrying out electrophoresis on the PCR product amplified in the step (2) by using agarose gel, separating a target band according to the size and the position of the target band, adding shrimp alkaline enzyme into the target band for digestion, and then respectively carrying out sequencing reaction;

(4) sequencing the digested PCR product in the step (3) by utilizing sequencing primers shown in SEQ ID NO. 3-8 to sequence exons 2,3 and 4 respectively to obtain a sequencing product;

(5) purifying and denaturing the sequencing product obtained in the step (4), and then sequencing by using a sequencer; and comparing the sequence obtained by sequencing with an HLA-IMGT database and analyzing to obtain the HLA-B locus allele type.

5. The detection method according to claim 4, wherein the amplification conditions of step (2): 5min at 95 ℃; 30s at 95 ℃, 25 s at 63 ℃ and 2min at 72 ℃ for 30s, and the total number of cycles is 40; 5min at 72 ℃; and finishing at 10 ℃.

6. The detection method according to claim 4, wherein the sequencing conditions of step (4): 20min at 96 ℃, 30s at 50 ℃ and 1min at 60 ℃ for 45s for 25 cycles.

Technical Field

The invention belongs to the technical field of gene detection, and particularly relates to an HLA-B locus allele typing kit and a detection method thereof.

Background

Human Leukocyte Antigens (HLA) are encoded by genes located on the short arm of human chromosome 6, classical HLA-I molecules include A, B and C sites, HLA-II molecules include DR, DQ and DP sites, and genes at each HLA site are linked and inherited in a haploid form, wherein the HLA-B site is the most complex site of allelic polymorphism found so far. The HLA-B locus allelic factor reported by WHO is 7255, the B locus allelic factor of Chinese population is 485, and the common allelic factor is 54.

The HLA-B locus plays an important role in allogeneic hematopoietic stem cell transplantation and organ transplantation, and is closely related to heredity, pathogenesis, disease progression, drug toxicity or adverse reaction, reproductive health, infertility and the like. Especially, compared with the traditional serotype, the HLA-B locus allelic gene typing has more accurate diagnosis and prognosis judgment of diseases. The clinical application field is as follows: the clinical value of HLA-B27 allelic typing in the prediction and diagnosis of ankylosing spondylitis; clinical value in predicting adverse drug reactions in patients, such as antiepileptic drug detection of gene B15: 02, antiviral drug Abacawei detection of gene B57: 01, anti-gout drug uric acid reduction of allopurinol detection of gene B58: 01, etc.; and HLA has relevance to immune infertility and habitual abortion. Therefore, the kit for accurately carrying out HLA-B locus allele typing prepared by the gene sequencing method has very important clinical application prospect and diagnosis and treatment values on diseases.

The gene Sequencing (SBT) technology is a gold standard of HLA genotyping, and the method for carrying out HLA-B locus allele genotyping by adopting the SBT technology is a method for carrying out full-length sequencing on 2 nd, 3 rd and 4 th exons with T cell important antigen presentation function on a B locus, so that not only can 2 alleles on the HLA-B locus of a patient be accurately sequenced, but also serotype, allele homozygote or heterozygote expression can be determined, and the HLA haplotype of a pathogenic gene can be further analyzed. The kit has the advantages of high accuracy, high specificity, high precision, small sample size, capability of realizing large-scale detection, short report time and the like.

Disclosure of Invention

The invention aims to provide an HLA-B locus allele typing kit and a detection method for carrying out HLA-B locus allele typing by using the kit, wherein a primer sequence for the sequencing reaction of 2 nd, 3 rd and 4 th exons of an HLA-B locus is further designed by designing a primer sequence covering the characteristics of various alleles of the HLA-B locus, and an experiment reaction system and conditions are simultaneously established and optimized for carrying out the detection of the HLA-B locus allele typing.

In order to achieve the purpose, the invention provides the following technical scheme:

an HLA-B locus allele typing kit comprises amplification primers for amplifying 2 nd, 3 rd and 4 th exon regions covering HLA-B loci and specific sequencing primers aiming at the 2 nd, 3 th and 4 th exon regions respectively;

the nucleotide sequence of the amplification primer is as follows:

an upstream primer BF: TCTCAGGGTCTCAGGGTCCG, as shown in SEQ ID NO. 1;

a downstream primer BR: CAGCCAGGCCAGCAACAATG, as shown in SEQ ID NO. 2;

sequencing primers for exon 2 were as follows:

upstream primer B2F: CCCAGGCTCCCACTCCAT, as shown in SEQ ID NO. 3;

the downstream primer B2R: GGGGAGTCGTGACCTGC, as shown in SEQ ID NO. 4;

sequencing primers for exon 3 were as follows:

upstream primer B3F: GGCCAGGGTCTCACA, as shown in SEQ ID NO. 5;

the downstream primer B3R: GGCGACATTCTAGCGC, as shown in SEQ ID NO. 6;

sequencing primers for exon 4 were as follows:

upstream primer B4F: AGATGCAAAGCGCCTGAA, as shown in SEQ ID NO. 7;

the downstream primer B4R: GGCTCCTGCTTTCCCTGA, as shown in SEQ ID NO. 8.

Further, the amplification system covering the 2 nd, 3 rd and 4 th exon regions of the HLA-B site comprises: upstream primer BF, downstream primer BR, 10 XBuffer, dNTP, Taq enzyme and DNA sample.

Further, the sequencing system for the 2 nd, 3 rd and 4 th exon regions comprises: PCR amplification products, B2F/B2R, B3F/B3R, B4F/B4R sequencing primers and Bigdye.

The detection method for HLA-B locus allelic gene typing by using the kit comprises the following steps:

(1) extracting DNA;

(2) amplifying the DNA sample extracted in the step (1) by using amplification sequences shown in SEQ ID NO. 1 and SEQ ID NO. 2 to obtain a DNA sequence covering HLA-B sites and containing exon regions 2,3 and 4;

(3) carrying out electrophoresis on the PCR product amplified in the step (2) by using agarose gel, separating a target band according to the size and the position of the target band, adding shrimp alkaline enzyme into the target band for digestion, and then respectively carrying out sequencing reaction;

(4) sequencing the digested PCR product in the step (3) by utilizing sequencing primers shown in SEQ ID NO. 3-8 to sequence exons 2,3 and 4 respectively to obtain a sequencing product;

(5) purifying and denaturing the sequencing product obtained in the step (4), and then sequencing by using a sequencer; and comparing the sequence obtained by sequencing with an HLA-IMGT database and analyzing to obtain the HLA-B locus allele type.

Further, the amplification conditions of step (2): 5min at 95 ℃; 30s at 95 ℃, 25 s at 63 ℃ and 2min at 72 ℃ for 30s, and the total number of cycles is 40; 5min at 72 ℃; and finishing at 10 ℃.

Further, the sequencing conditions of step (4): 20min at 96 ℃, 30s at 50 ℃ and 1min at 60 ℃ for 45s for 25 cycles.

Has the advantages that: the kit is a HLA-B locus allele typing kit prepared for the first time based on a gene sequencing method, and comprises an amplification primer covering an HLA-B locus and sequencing primers aiming at exons 2,3 and 4, so that various allele types of the HLA-B locus can be directly analyzed, the interference of gene sequences of HLA-A and C loci with extremely high homology with the allele types is avoided, and the accuracy of a typing result is improved. Drawings

FIG. 1 is an electrophoresis diagram of the product of DNA amplification reaction of HLA-B site.

FIG. 2 is a graph of the sequencing of exon 2 of HLA-B locus showing the results of B locus allelic typing: HLA-B15: 01, B51: 01, arrows indicate exon 2 regions within the black bar.

FIG. 3 is a graph of the sequencing of exon 3 of HLA-B locus showing the results of B locus allelic typing: HLA-B46: 01, arrows indicate the 3 rd exon region within the black bar.

FIG. 4 is a graph of the sequencing of exon 4 of HLA-B locus showing the results of B locus allelic typing: HLA-B46: 01, B51: 01, arrows indicate the 4 th exon region within the black bar.

Figure 5 is a schematic representation of the HLA naming convention of the WHO.

Detailed Description

The present invention is further described below with reference to specific examples, which are only exemplary and do not limit the scope of the present invention in any way. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention, and that such changes and modifications may be made without departing from the spirit and scope of the invention.