贵州苗族人群MICA和MICB基因多态性及单倍型分析

Polymorphism and Haplotype Analysis of MICA and MICB Alleles of Miao Population in Guizhou Province

为了探讨贵州苗族人群主要组织相容性复合体(major histocompatibility complex,MHC)Ⅰ类链相关基因(MHC classⅠchain-related gene,MIC gene)MICA和MICB的分布特征,以丰富基因数据库中相关信息,进而研究某些疾病的遗传特征和进化史,采用基于序列特异性引物的聚合酶链反应(PCR-sequence-specific primer,PCR-SSP)和基于序列分型的聚合酶链反应(PCR-sequence-based typing,PCR-SBT)检测150例中国贵州苗族人群外周血DNA样本,分析该人群的MICA和MICB基因分布,用卡方检验对MICA和MICB基因分布频率的差异进行评估。基因分型结果显示,中国贵州苗族人群中MICA*019、MICA*045、MICA*008:04、MICA*002:01、MICA-A9、MICA-A4、MICB*005:02和MICB*002等位基因的频率显著高于其他等位基因。MICA和MICB等位基因的单倍型分析显示,MICA*019-MICB*005:02和MICA*008:04-MICB*005:02两种单倍型的分布频率较高,分别为17.40%和16.30%。PCR-SSP和PCR-SBT分析显示,MICA*010与MICB*005:02、MICA*002:01与MICB*005:02以及MICA*009:01与MICB*005:02这3种MICA和MICB等位基因存在连锁不平衡(P<0.01)。上述结果表明,中国贵州苗族人群MICA和MICB基因具有多态性且存在显著的连锁不平衡。本研究为中国少数民族MIC基因序列数据库提供了人群样本数据,该数据为研究MICA和MICB基因在同种异体移植和疾病易感性中的可能作用提供了基础资料。

In order to explore the distribution characteristics of major histocompatibility complex(MHC)classⅠchain-related(MIC)genes MICA and MICB in the Miao population of Guizhou to establish a genetic database that can be used to study the genetic characteristics and evolutionary history of certain diseases,PCR-sequence-specific primer(PCR-SSP)and PCR-sequence-based typing(PCR-SBT)methods were used to analyse the distribution of MICA and MICB genes from 150 Miao people in Guizhou Province by detecting their peripheral blood DNA samples.The differences in the distribution frequencies of MICA and MICB genes were analyzed and evaluated by the chi-square test.The genotyping results showed that the frequencies of MICA*019,MICA*045,MICA*008:04,MICA*002:01,MICA-A9,MICA-A4,MICB*005:02 and MICB*002 alleles were significantly higher than those of other alleles in the Miao population.Analysis of MICA-MICB gene sequence haplotypes revealed that the distribution frequency of MICA*019-MICB*005:02 and MI-CA*008:04-MICB*005:02 was higher,which were 17.40%and 16.30%,respectively,but only MICA*010-MICB*005:02,MICA*002:01-MICB*005:02 and MICA*009:01-MICB*005:02 were the MICA-MICB haplotypes with significant linkage disequilibrium(P<0.01).These results indicate that the MICA and MICB genes of Miao people in Guizhou are polymorphic and have significant linkage disequilibrium.The study provides experimental data for improving the MIC gene sequence database of ethnic minorities in China.These results could serve as the basis for future studies on the potential role of MICA and MICB in allogeneic organ transplantation and disease susceptibility in related ethnic groups.