贵州三个民族亚甲基四氢叶酸还原酶基因的遗传多态性

目的研究贵州汉族、布依族、苗族亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase，MTHFR)基因多态性，为贵州少数民族基因多态性数据库的建立提供相关数据。方法应用聚合酶链反应及限制性片段长度多态性检测贵州荔波汉族、布依族、雷山苗族MTHFR基因两个单核苷酸(677及1298位)多态位点的基因频率及基因型频率。结果汉族、布依族、苗族MTHFR677位T等位基因的分布频率分别是22．8％，16．1％，10．6％，MTHFR1298位C等位基因的分布频率分别是28．9％，39．1％，48．7％，677CT／1298AC双杂合子的分布频率分别是16．66％，22．7％，11．1％。在苗族还发现1例677TT／1298CC双纯合子。结论．MTHFR C677T和A1298C多态性存在群体差异；贵州雷山苗族、荔波布依族．MTHFR 1298位有较高的C等位基因频率，贵州雷山苗族MTHFR 1298位C等位基因频率是目前文献报道最高的民族。

5,10-methylenetetrahydrofolate reductase polymorphism in three nationalities of Guizhou in China

Objective To study the genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR)among the Han, Buyi and Miao populations in Guizhou and to provide genetic data for establishment of the genetic polymorphism bank of Guizhou Minorities. Methods The technique of polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) was used to detect the genotype and allele frequencies at two mononucleotide sites (677 and 1298) of MTHFR among the Han population in Libo county, the Buyi population in Libo county and the Miao population in Leishan county. Results At the site of 677,the T allele frequencies were found to be 22.8%,16.1%, 10.6%, for the Han, Buyi, Miao populations respectively. At the site of 1298, the C allele frequencies were 28 9%, 39 1%, 48.7% for the Han, Buyi, Miao populations respectively. The frequencies for the combined heterozygote of 677CT/1298AC were 16.66%, 22.7%, 11.1% for the three populations respectively. Moreover, one case with combined homozygote of 677TT/1298CC was seen in the Miao population. Conclusion The polymorphisms of the two mononucleotide sites (677 and 1298) of MTHFR are diverse in different populations. The C allele frequencies at the site of MTHFR 1298 of the Miao population in Leishan county and the Buyi population in Libo county are high, and the C allele frequency in the Miao population is higher than those hitherto reported in literature.