广西红水河流域长寿人群MTHFR C677T 基因多态性与血脂水平的相关性

目的 探讨亚甲基四氢叶酸还原酶(MTHFR)基因C677T位点的多态性与广西红水河流域长寿人群的血脂水平及长寿的关系.方法 应用聚合酶链反应—限制性片段长度多态性(PCR-RFLP)方法对505例该流域90岁以上壮族长寿老人(长寿组)、普通健康壮族中老年人468例(非长寿组)进行基因分型,并检测血压、体质指数、血脂(TC、TG、HDL、LDL)等指标.结果 长寿组和对照组C、T等位基因频率分别为80.2％、19.8％和85.0％、15.0％；两组3种基因型(CC、CT、TT)频率分别为65.5％、29.3％、5.2％和73.9％、22.2％、3.8％；等位基因及基因型频率在两组间差异显著,且有T等位基因在长寿组女性中富集现象,而男性中无此趋势.在血脂水平上除HDL外,长寿组的TC、TG、LDL水平显著高于非长寿组(P＜0.01).进一步按MTHFR C677T基因型和性别分层后发现,长寿组中女性突变基因型(CT/TT)的TC、TG及LDL水平明显高于非突变基因型(CC)；而男性各血脂水平分别在两组3种基因型间未发现有明显差异.结论 MTHFR基因C677T位点的多态性与血脂水平及长寿有一定的关系,并呈性别特异性,可能是红水河流域长寿现象的分子遗传学基础之一.

Association Between the MTHFR C677T Polymorphism and Serum Lipid Levels and Longevity in the Long-Lived Cohort in Guangxi Hongshuihe River Basin

Aim To investigate the plausible relationship between the polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene at C677T locus and serum lipid levels and longevity in the long-lived cohort residing in Guangxi Hongshuihe River Basin. Methods Genotyping was performed with PCR-RFLP technique for 505 long-lived Zhuang individuals inhabiting in Guangxi Hongshuihe River Basin whose ages were 90 and above (long-lived group, LG) and 468 ethnic- and geographic-matched healthy mid-aged or elderly controls (non-long-lived group, non-LG). Association analysis were undertaken between MTHFR C677T genotypes and serum lipids (total cholesterol, TC triglyceride, TG high density lipoprotein, HDL low density lipoprotein, LDL). Results The allelic (C and T) and genotypic (CC, CT, and TT) frequencies of the LG and non-LG were 80.2%, 19.8% versus 85.0%, 15.0% and 65.5%, 29.3%, 5.2% versus 73.9%, 22.2%, 3.8%, respectively, which displayed significant differences between the two tested groups, with an overrepresentation of T allele in long-lived females specially, but not in males. On lipid profiles, the levels of TC, TG, LDL in LG are significantly higher than that in the non-LG. After stratifying by MTHFR C677T genotype and gender, the TC, TG, and LDL levels were noted dramatically higher in females but not in males harboring the mutant genotype (CT/TT) than that of the non-T carriers (CC) in the LG. Conclusions Our data suggest that there was a femalespecific association between the MTHFR C677T polymorphism and serum lipid levels and human longevity, which may be one of the molecular genetic basis for the longevity in the Guangxi Hongshuihe River Basin.