贵州四个民族人群线粒体DNA编码区的多态性

目的研究贵州土家族、侗族、仡佬族和彝族人群线粒体DNA（mtDNA）编码区的核苷酸多态性。方法采用PCR-RFLP技术和DNA测序法对贵州4个群体145例样本mtDNA编码区的8个SNP基因座及COⅡ/tRNAlys基因间9 bp缺失进行多态性分析。结果贵州4个民族群体的9 bp缺失频率依次为土家族18.4%,侗族29.7%,仡佬族25%,彝族16.7%,平均缺失频率为22.8%;在8个SNP基因座中,A10398G、C10400T突变在4个群体中较普遍;A663G、C5178A和G12406A突变在部分民族群体中也有较高的频率;共检测出14种单倍型,其中仡佬族11种,土家族10种,侗族8种,彝族6种。结论贵州4个民族群体mtDNA编码区可能存在不同的突变热点,在等位基因和单倍型分布频率上存在一定差异。

The Polymorphism of Mitochondrial DNA Coding Region in Four Ethnic Populations from Guizhou

Objective To study the nucleotide polymorphism of mitochondrial DNA（mtDNA） coding region in Tujia,Dong,Gelao and Yi ethnic populations from Guizhou.Method The 8 SNP loci in the coding region and 9bp deletion COⅡ/tRNA^lys intergenic region of 145 samples from four ethnic populations were detected by PCR-RFLP and direct sequencing.Result The frequencies of 9bp deletion in Tujia,Dong,Gelao and Yi populations were 18.4%,29.7%,25%and 16.7% respectively,and the average frequency was 22.8%.A10398G,C10400T mutation were very common in four ethnic populations,and the frequencies of A663G,C5178A and G12406A mutation were higher in the some populations;a total of 14 different haplotypes were identified in 145 samples, and 11,10,8,6 haplotypes were observed in the Tujia,Dong,Gelao and Yi populations respectively.Conclusion There are different mutational hot spots of mtDNA coding region in the four ethnic populations from Guizhou.The frequencies of allele and haplotype distribution of 8 mtDNA SNP loci are different among four ethnic populations.