汉族人群ApoE-CⅠ-CⅡ基因簇及其与血脂水平关系的研究

目的探讨ApoE-CⅠ-CⅡ基因簇之间的遗传联系及其对汉族人群血脂水平的影响.方法采用横断面调查方法对350例汉族人群[年龄(63.64±12.0)岁]进行基因多态性和血脂水平分析.ApoE基因多态性检测用m山ti-ARMS快速分型法,ApoCI启动子HpaI多态性及ApoCⅡ基因AvaⅡ位点多态性均采用PCRRFLP;血脂测定在全自动化分析仪上进行.结果人群中ApoE基因E3/3为主要基因型(73.40%),E2/2、E2/4和E4/4型均较少见(＜1%);ApoCI基因以H1/1基因型为主(79.7%),纯合子突变型H2/2少见(1.70%);未发现ApoE和ApoCI基因多态性与各血脂水平间有统计学意义的联系;ApoCⅡ基因中T1、T2等位基因型频率分别为70.7%和29.3%,T1/2携带者血TG水平[(1.49±0.96)mmol/L]显著高于T1/1携带者[(1.29±0.72)mmol/L],P＜0.05.ApoE、C1和CⅡ各位点基因型和等位基因型分布在男女性别间差异均无显著意义.ApoE和ApoCI两基因在研究人群中未出现连锁不平衡现象.结论人群中Apoe和ApoCI基因未出现连锁不平衡分布,其多态性对各血脂水平间也未产生有统计学意义的影响,可能是汉族人群心血管疾病发病率较低的一个因素.

Apolipoproptein E-CⅠ-CⅡ gene cluster and its effect on serum lipid levels

OBJECTIVE: To investigate the allele frequencies of the apolipoprotein (apo)E-CI-CII cluster gene in Hans of Chinese, and its relation to serum lipid levels. METHODS: The study subjects consisted of healthy individuals (male: 196, female: 154; average age: 63.6 +/- 12.0 years) who were randomly selected from health screening. ApoE genotypes were identified by multi-AMRS PCR and both the ApoCI promoter polymorphisms and AvaII polymorphisms of the apoCII gene were detected by using PCR-RFLP. The serum lipid levels were determined using an automatic chemistry analyzer. RESULTS: For ApoE gene, the frequency of E3/3 was 73.4%, it represents the most common genotype from of the polymorphism. The frequencies of E2/2, E2/4 and E4/4 genotypes were all smaller than 1%. For the ApoCI locus, the frequencies of H1/ 1, H2/2 genotypes were 79.7% and 1.7%, respectively. Both the ApoE and ApoCI polymorphisms showed the lack of association with plasma levels in this population. The linkage disequilibrium between ApoE with ApoCI wasn't found, either. The allele frequencies of ApoCII gene were T1 : 70.7% and T2 : 29.3%, respectively. The TG level in subjects carrying with T1/2 (1.49 +/- 0.96 mmol/l) was significant higher than that in subjects with T1/1 (1.29 +/- 0.72 mmol/l), P < 0.05. No significant differences were found between male and female in genotype distribution and allele frequencies of the ApoE-CI-CII gene cluster. CONCLUSION: This result suggested that it might be one of the factors in explaining the lower prevalence rate of atherosclerosis in the China population.