饮酒和载脂蛋白AI基因启动子-75bp处G/A置换对凉山彝汉两民族血浆载脂蛋白AI水平的影响(英文)

Influence of Alcohol and the G/A Substitution at-75bp Promoter Region of Apolipoprotein AI Gene in Determining Plasma Apolipoprotein AI Levels in Yi and Han Chinese

目的：研究载脂蛋白AI启动子-75bP处G／A嘌呤置换以及饮酒对凉山彝族汉两民族血浆载脂蛋白AI水平的影响。方法：现场调查中随机抽样742名凉山州彝汉健康居民，包括三个人群样本：彝族农民、彝族移民、和汉族居民。采集清晨空腹血样10ml／人。全项血脂和脂蛋白水平测定。从冷藏血凝块中抽提基因组DNA，经PCR扩增，进行片段长度多态性分析。结果：根据饮酒量将人群分为四组：不饮酒者、1－25克／天饮酒者、26－75克／天饮酒者、75克／天以上饮酒者。结果显示，随着饮酒量的增加，血浆HDLC和apoAI水平逐渐升高，在彝族农民样本和汉民样本中有非常显著的统计学意义。三人群样本间的A等位基因频率相似。A等位基因携带者与GG基因型携带者之间的各项血脂水平没有显示出差异。但在不饮酒者中，A等位基因携带者的apoAI水平明显高于GG基因型携带者；而饮酒者中，A等位基因携带者的apoAI和HDLC水平明显低于GG基因型携带者，上述差异在城镇人群中显示出统计学意义（P＜0．05）。不饮酒者中，G／A置换可以解释18％的个体间apoAI水平变异（F＝8．94，P＜0．01）。结论：结果表明，适量的饮酒和apoAI基因-75处G／A置换多态性均可使冠心病危险降低，但A等位基因的这种有益作用可能被饮酒抵消。

Objective: To study the influence of alcohol and a common polymorphism in thehuman apolipoprotein AI gene promoter at a position 75bp upstream of the transcriptional startsite on plasma lipid levels. Methods: 742 healthy Yi and Han subjects all above 15 years old formedthe total population which was divided into three samples, namely, Yi-farmer sample, Yi-emigrantsample and Han-resident sample for this study. All estimations of plasma lipids andapolipoproteins were carred on through an auto-analyzer. Genetic DNA was prepared from the clots usingTriton x-100 lysis techniqve. Amplification of a 432bp fragment of the apoAI gen promoter wasperformed via the PCR, followed by restriction digestion, electrophoresis and identificaton of thegenotypes involved. Data analysis was done at last. Results: Four groups of alcohol consumptionwere defined: non-drinkers, 1-25g/day, 26-75g/day and>75g/day. When the four alcoholconsumption groups were compared, plasma HDLC and apoAI levels became elevated continuously as thealcohol consumption increased with no evidence of threshold effects in the sample of Yi-farmersand the sample of Han people. Similar association was found in the sample of Yi-emigrants,but hadnot statistical significance. The freqeuencies of the A allele of the three samples were similar, andno significant difference of lipid and apolipoprotein levels was found between subjects with andwithout A allele in three samples. But, In Han and Yi-emigrant samples, the drinkers withgenotypes of GG had higher plasme HDLC and apoAI levels than non-drinkers with same genotypes,the drinkers with A allele had lower plasma HDLC and apoAI levels than drinkers without Aallele, and the non-drinkers with A allele had higher levels of apoAI than non-drinkers withgenotypes of GG. It is estimated that 18% of the variability of plasma apoAI level could be explained bythe G/A polymorphism in non-drinkers of Yi-emigrants (F=8.94, P<0. 01). Conclusions: Thepresent data suggest that moderate alcohol consumptiopn and the G to A substitution could makethe risk of CHD lower, but the beneficial effects of the G to A substitution will be negated byalcohol consumption.