中国四个人群中MICA基因多态性研究(英文)  

Studies on the polymorphism of MICA gene in four Chinese populations

作　　者：肖翠英[1] 张思仲[1] 程璐[1] 敬慧娥[1] 侯一平[1] 褚嘉佑[2] 张戈[1] 吴谨 

机构地区：[1]华西医科大学附属第一医院医学遗传学教研室,成都610041 [2]中国医学科学院医学生物学研究所

出　　处：《中华医学遗传学杂志》2000年第6期424-428,共5页Chinese Journal of Medical Genetics

基　　金：国家自然科学基金重大项目!(3999342 0);美国纽约中华医学基金!(98- 675)

摘　　要：目的　了解中国 4个人群中 MICA基因第 5外显子 (GCT) n位点的遗传多态性并从遗传学的角度提供白马藏族起源的初步证据。方法　 411个无血缘关系个体的血标本或唾液标本分别采自四川平武县白马藏族、西藏拉萨和云南中甸县藏族、成都地区汉族以及四川茂县羌族。以 1对跨越 MICA基因第 5外显子 GCT重复序列区的引物扩增基因组 DNA,产物用变性聚丙烯酰胺凝胶电泳分离 ,银染显色分析。结果　在 4个群体中均检测出 5种已报道的等位片段 ,并均以 A5最常见 ,在白马藏族、藏族、成都汉族和羌族中的频率分别为 0 .32 5、0 .345、0 .390和 0 .319。 A5 .1在成都汉族和羌族中占第 2位 ,频率分别为0 .2 30和 0 .2 93,A4和 A9在白马藏族和藏族中分别占第 2位 ,频率分别为 0 .2 5 4和 0 .2 72。上述各等位基因分布在 4个群体中存在差异 ,尤其是白马藏族与其它 3个群体之间存在显著差异。结论　MICA基因在迄今已研究的不同群体中都有 5种等位基因 ,提示 MICA基因在各群体间是在相似选择压力下产生 ,对维持群体的生理功能有着必不可少的作用。各民族Objective To understand with greater clearness the genetic polymorphism of (GCT)n repeat of MHC class I chain related gene A (MICA)in some Chinese populations and provide preliminary genetic evidence for the independent origin of Chinese Baima Tibetan (BMT). Methods ACD blood or saliva specimens of 411 unrelated individuals from four Chinese populations were collected. A primer pair spanning exon 5 of MICA gene was used to amplify the GCT region. Alleles were detected by PCR and denaturing PAGE. Comparison of the allelic distributions among the four populations was carried out. Results Five previously reported alleles have been observed in all the four populations, but the allelic distributions are different from one another. The most frequent allele is the A5 in all the four populations (0.325 in BMT, 0.345 in Tibetans, 0.390 in Chengdu Hans and 0.319 in Qiangs). A5.1 allele is the second most frequent allele in Chengdu Hans (0 230) and in Qiangs (0.293), while the second most frequent alleles for BMT and Tibetans are A4 (0.254) and A9 (0.272) respectively. The distribution of alleles in BMT is significantly different from that in the other three populations. Conclusion Alleles of MICA gene exon 5 are conservative in all populations studied so far. The results suggest that genetically BMT might be an independent ethnic population.

关 键 词：MHCⅠ类链 相关基因A 三核苷酸 多态性 藏族 

分 类 号：Q346.5[生物学—遗传学] Q524