载脂蛋白E基因多态性与血管性痴呆的关系

The relationship between gene polymorphism of apolipoprotein E and vascular dementia

目的探讨载脂蛋白E(ApoE)基因多态性与血管性痴呆的关系,并分析其可能的作用机制。方法应用聚合酶链反应-限制性片段长度多态性技术,检测65例血管性痴呆患者(血管性痴呆组)和120名健康受试者(对照组)的ApoE基因型和基因频率;同时对血清总胆固醇、甘油三酯、低密度脂蛋白和高密度脂蛋白进行检测,分析ApoE基因多态性对血脂代谢的影响。结果血管性痴呆组与对照组均以ε3/3基因型出现频率最高,但血管性痴呆组患者的ε4基因出现频率(14.6%)显著高于对照组(4.6%,P<0.01)。血管性痴呆组血清总胆固醇水平明显高于对照组(P<0.05)。在血管性痴呆组,ε4基因具有升高血清总胆固醇水平的作用;而在正常对照组,ε2基因具有降低血清甘油三酯和低密度脂蛋白水平的作用,说明ε4基因与血清总胆固醇水平升高具有相关性。结论ApoEε4是血管性痴呆发病的的遗传易感因子;血管性痴呆患者存在血脂代谢紊乱,且受ApoE基因的调控,ApoE基因可能通过引起血脂代谢紊乱而增加血管性痴呆发病危险性。

Objective To study the relationship between gene polymorphism of apolipoprotein E and vascular dementia(VD)and analyze the potential role of ApoE played in pathogenesis of VD.Methods The genotype and frequencies of ApoE alleles were detected by PCR-RFLP(restriction fragment length polymor-phism)technique in65patients with VD(VD group)and120healthy controls(control group),and the serum levels of total cholesterol(TC),triglyceride(TG),low density lipoprotein(LDL)and high density lipoprotein(HDL)were also measured.Re sults Genotypeε3/3occurred the highest frequency in both VD group and control group,but patients with VD had a significantly higher frequency ofε4allele(14.6%)than that in con-trols(4.6%,P<0.01).The serum level of TC in patients with VD was much higher than that in controls(P<0.05).Alleleε4was associated with increasing serum level of TC in VD group,whileε2allele was associated with decreasing serum levels of TC and LDL in control group.It demonstrated that there was association be-tweenε4gene and increased level of TC.Con clu sion ApoEε4is a susceptible genetic factor for VD.There is metabolic disturbance of blood lipids in VD and it is modulated by Apo E gene.Thus Apo E may in-crease the pathogenic risk for VD through resulting in dysbolism of blood lipids.[