目的:探讨载脂蛋白E(ApoE)基因多态性与广西红水河流域长寿人群血脂水平及长寿的相关性。方法:采用PCR—RFLP技术对该地区521名壮族长寿老人(≥90岁,长寿组)和496名普通健康人(40~69岁,对照组)进行Ap0E基因分型,并检测血压、血糖及血脂(TC、TG、HDL—C和LDL—C)等指标。结果:(1)在研究人群中,ApoE基因型频率以E3/3为最高,E2/3、E3/4次之,E2/2、E4/4最低;长寿组等位基因ε2和基因型E2/X的频率均高于对照组,而ε4和E4/X的频率均低于对照组,这些趋势无性别差异。(2)长寿组的TC、HDL—C和LDL—C水平均高于对照组,而TG水平低于对照组;组内分析发现,无论是长寿组或对照组、男性或女性.当基因型从E2/X向E3/3和E4/X变化时,血清TC及LDL-C水平逐渐增加,而TG水平逐渐减少.结论:广西红水河流域长寿人群富集ApoE优势基因型,并与血脂水平密切相关,可能是该流域长寿现象的分子遗传学基础之一。
Objectives To investigate the correlations between apoprotein E (ApoE) gene polymocphisms and serum lipid levels, longevity in the long-lived individuals living along the Hongshuihe basin in Guangxi. Methods PCR-RFLP technique was employed to genotype the ApoE gene in 521 long-lived subjects (more than 90 years old, long-lived group) and geographic and ethnic matched healthy controls (40-69 years old, non-long-lived group). Lipid levels (TC, TG, HDL-C and LDL-C), blood pressure and blood glucose were measured. Results In the overall population studied, the most dominant ApoE genotype was E3/E3, followed by E2/3 and E3/4, with E2/2 and E4/4 accounting for the least prevalent; allele ~2 and genotype E2/X were highly expressed while allele ~4 and genotype E4/X were meagerly expressed in long-lived group than those in non-long-lived group; and these trends did not change after sex stratification. The serum levels of TC, HDL-C and LDL-C were higher, while the level of TG was lower in long-lived group than those in non-long-lived group. Within group analysis revealed that an increasing tendency of TC and LDL-C levels and a decreasing trend of TC level occurred when genotype was switched from E2/X toward E3/E3 and E4/X, irrespective of whether the subjects were male or female, were in long-lived group or in non-long-lived group. Conclusions Favorable ApoE genotypes appeared to cluster in the long-lived cohort inhabiting in Guangxi Hongshuihe basin and exerted beneficial effect on their lipid levels, which may be one of the molecular bases of the longevity in this area.