中国南北汉族人群HLA-A*02等位基因的分布差异

目的 研究中国南北汉族人群中HLA-A*02等位基因的分布并比较其差异性。方法 采用PCR-SBT方法,对随机抽取的经PCR-SSP方法确认为HLA-A*02阳性的208例南方和129例北方汉族骨髓志愿供者进行序列分型。结果 南、北汉族人两个群体中均检出具有不同基因频率的6种A*02等位基因(A*020101、A*0203、A*0205、A*0206、A*0207和A*0210)。南方汉族人中A*0207(37%)为优势等位基因,A*020101(31%)、A*0203(16%)和A*0206(14%)比较常见;而北方汉族人则以A*020101(48%)为优势等位基因,A*0206(21%)和A*0207(23%)比较常见。两个群体中的A*02等位基因总体分布以及A*020101、A*0203和A*0207的相对频率均存在显著性差异。在高、低分辨率两个水平上,南方和北方汉族A*02杂合度分别高于90%和80%,并且低分辨率A*02纯合子在高分辨率水平上表现高度多样性并呈现一定的分布规律。结论 HLA-A*02等位基因在中国南、北汉族人群中的分布呈现高度杂合和遗传多样性并具有显著性差异,HLA-A*020101、A*0203和A*0207可作为人类学研究中区分中国南北汉族人群的遗传标志。

Difference in HLA-A*02 allele distribution between Han populations in south and north China

Objective To investigate the distributions of HLA-A*02 alleles in Han populations and compare their difference between the south and north in China. Methods A total of 208 individuals from south China and 109 from north China were randomly selected from registered bone marrow donors in Chinese Han population, who were tested positive for HLA-A*02 alleles by PCR with sequence-specific primers (PCR-SSP). Genotyping of the alleles was performed using PCR-sequence-based typing (PCR-SBT). Results Six different HLA-A*02 alleles (A*020101, A*0203, A*0205, A*0206, A*0207 and A*0210) were identified in the two Chinese Han populations, of which A*0207(37%) was the predominant allele in southerners and A*020101(48%) in the northerners. A*020101(31%), A*0203(16%) and A*0206(14%) were common alleles in the southerners in comparison with A*0206(21%) and A*0207(23%) alleles in the northerners. The overall distribution of A*02 alleles and the frequencies of A*020101, A*0203 and A*0207 in the two populations differed significantly. The heterozygosity of A*02 in the southerners and northerners was higher than 90% and 80% at the high- and low-resolution levels, respectively, and the distribution of A*02 homozygote at low-resolution level in both populations showed diversity and regularity at high-resolution level. Conclusions HLA-A*02 alleles possess high heterogeneity and genetic diversity in Chinese Han population with significantly different distributions in the two populations. HLA-A**020101, A*0203 and A*0207 may serve as the genetic markers for dividing Chinese Han individuals into southerners and northerners in anthropological studies.