广东汉族人群HLA-B基因多态性研究

目的调查广东汉族人群HLA-B位点基因多态性，比较不同人群HLA—B等位基因频率分布特征。方法应用测序技术测定562名广东汉族人HLA-B位点第2、3、4外显子序列，比对数据库得到分型结果，计算HLA-B等位基因频率并与不同人群进行比较。结果共检测到59种HLA-B等位基因，其中6种等位基因频率≥5％，分别是HLA-B＊4601（14．5％），HLA-B＊400101（14．4％），HLA—B＊1502（11．5％），HLA—B＊1301（8．6％），HLA-B＊5801（8．1％）和HLA-B＊380201（6．4％）。这6种等位基因的等位基因频率合计为63．5％。同时，检测到30种等位基因频率〈0．5％的HLA-B等位基因，这30种等位基因的等位基因频率合计为4．9％。广东汉族人群HLA-B等位基因频率总体分布与中国香港华人、新加坡华人比较差异无统计学意义（P〉0．05），但与日本人比较差异有统计学意义。结论分析了HLA-B基因在广东汉族人群中的分布特征，提供了较完整的HLA-B等位基因频率分布资料，为遗传学及疾病相关性等研究提供了重要的参考数据。

HLA-B gene polymorphism detected by high-resolution sequence-based typing in Guangdong Han populations

Objective To investigate the genetic polymorphism of HLA-B locus in Guangdong Han population and compare the characteristic of the allele frequency distribution with that in other populations. Methods A total of 562 cord blood samples from Guangzhou Cord Blood Bank were analyzed by sequence-based typing. Then the sequences encompassing exons 2, 3, and 4 for HLA-B gene were analyzed by direct sequencing of PCR products. The allele frequency distribution of HLA-B in this population was compared with that in other populations. Results A total of 59 different HLA-B alleles were detected, and among them were 6 HLA-B alleles with frequencies higher than 5%: HLA-B*4601 (14.5%),HLA-B*400101 (14.4%),HLA-B*1502 (11.5%),HLA-B*1301 (8.6%), HLA-B*5801 (8.1%) and HLA-B*380201 (6.4%); the total frequency of these six alleles was 63.5%. At the same time, there were 30 kinds of HLA-B allele with frequencies lower than 0.5%; the total frequency of these alleles was 4.9%. Maximum variation at HLA-B was seen in the HLA-B*15 allele family (nine alleles). Comparison of the HLA-B frequencies in different populations showed a close relationship of Guandong Han population with the Chinese populations from Hong Kong and Singapore, respectively. Conclusion The results have shown the characteristic of HLA-B distribution and provided more accurate genotypic data that may serve as normal reference value for the Han population in Guangdong, China.