中国家族性Alzheimer病的载脂蛋白E基因型分析

ApoE genotype analysis in Chinese familial Alzheimer disease

目的 研究中国家族性 Alzheim er病 (familial Alzheimer disease,FAD)家系中载脂蛋白 E(apolipoprotein E,Apo E)基因型和等位基因频率的分布。方法 应用聚合酶链式反应 -限制性片段长度多态性(polym erase chain reaction- restriction fragment length polymorphism,PCR- RFL P)技术对两个 AD家系 (家系 为130人 ,家系 为 2 3人 )和 5 5例正常对照组的 Apo E基因型进行分析。结果 在家系 成员中 ,等位基因 ε2、ε3和ε4频率分别为 9.2 %、70 .4 %和 2 0 .4 % ,其中 AD患者的基因型均为 3/ 4型 ;家系 中 ,等位基因 ε2、ε3和 ε4频率分别为 8.7%、71.7%和 19.6 % ,其中 AD患者也均为 3/ 4型 ;对照组等位基因分布为 9.1%、84 .5 %、6 .4 % ,其中 3/ 4基因型占 11%。结论 中国 FAD的 Apo Eε4等位基因频率均明显高于正常人 ,提示 Apo Eε4等位基因不仅是散发性 Alzheim er病 (sporadic Alzheimer disease,SAD)发病的危险因素 ,也是中国 FAD患者发病的危险因素。

Objective To calculate the frequencies of apolipoprotein E(ApoE) alleles and genotype in Chinese familial Alzheimer disease. Methods The polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) technique was used to analyze the ApoE genotype of two families of familial Alzheimer disease(FAD)(130 members and 23 members respectively) and 55 non-dementia elderly controls. Results The allelic frequencies of ε2,ε3 and ε4 were 9.2%,70.4% and 20.4% in familyⅠ(Whose AD patients were all of 3/4 type);8.7%,71.7% and 19.6% in familyⅡ(Whose AD patients were all of 3/4 type);9.1%,84.5%,and 6.4% in non-dementia elderly controls(11% were of 3/4 type). Conclusion The similarity of ApoE ε4 allelic frequency in FAD showes that the ApoE ε4 is not only a risk factor for sporadic Alzheimer disease(SAD),but also the one for FAD,which may take an important role in genetic procession.