北京市城区学龄儿童载脂蛋白E多态性与血脂谱水平的关系

Relationship between gene polymorphism at the apolipoprotein E locus and serum lipid profile in urban children of school age in Beijing

目的 了解载脂蛋白E(ApoE)基因多态性与儿童血脂谱水平的关系。方法 采用聚合酶链反应 限制性内切酶图谱分析法 ,对 30 7名 7～ 11岁在校儿童进行血脂谱水平测定及ApoE基因多态性检测。结果 30 7名儿童最常见基因型E3 3检出率为 5 4 7% ,其他基因型依次为E4 3(2 3 8% )、E4 4(9 1% )、E3 2 (8 1% )、E4 2 (3 9% )、E2 2 (0 3% ) ,不同性别基因型构成的差异无显著性 ;常见等位基因E3频率为 70 7% ,E4、E2分别为 2 3 0 %和 6 4% ,其中E4频率明显高于国内其他报道 ,E2频率接近于国内报道 ;男童E4 3、E3 3基因型总胆固醇 (TC ,4 19、4 2 9、3 41mmol L)、低密度脂蛋白 胆固醇 (LDL C)、载脂蛋白AⅠ (ApoAⅠ )、载脂蛋白B(ApoB)水平高于E3 2基因型 ,E4 2基因型TC(4 2 8和 3 41mmol L)、ApoAⅠ水平高于E3 2基因型 ,女童不同基因型血脂谱水平的差异无显著性 ;高胆固醇组与正常组儿童ApoE HhaⅠ位点基因型分布比较差异无显著性 ;ApoE2可使TC水平降低 0 377mmol L ,LDL C水平降低 0 32 9mmol L。结论 ApoE基因多态性与男童血清胆固醇水平相关 ,E2等位基因携带者TC、LDL C、ApoB水平最低。

Objective To study the relationship between gene polymorphism at the apolipoprotein E(ApoE) locus and serum lipid levels in children of school age. Methods Blood samples were collected from 307 normal children aged 7 to 11 years, including 150 boys and 157 girls, and their serum lipid profile, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), apolipoprotein B(apoB), apoprotein A1 (ApoAⅠ) and lipoptoein α[Lp(α)], were detected and their ApoE-HhaⅠgene polymorphism were tested by the PCR-RFLP method. Results The detection rates for the most frequent genotype ApoE3/3 was 54.7%,other genotypes E4/3, E4/4, E3/2, E4/2 and E2/2 were 23.8%, 9.1%, 8.1%, 3.9% and 0.3%,respectively, in 307 children, with no significant difference between girls and boys(P>0.05). Frequency of the often seen allele E3 was 70.7%, and that of E4 and E2 was 23.0% and 6.4, respectively, with E4 significantly higher than and E2 similar to that in the other domestic reports. The levels of TC、LDL-C、ApoAⅠand ApoB were higher in boys with genotypes E4/3 and E3/3 than those with genotypes E3/2 and E4/2. Levels of TC and ApoAⅠin the boys with genotype E3/2 were higher, with TC of 4.28 mmol/L and ApoAⅠ of 3.41 mmol/L. There was no significant difference in serum lipid levels of girls with different genotypes(P>0.05). There also was no significant difference in the ApoE-Hha Ⅰ genotype distribution between normal children and those with high TC. ApoE2 could decrease the level of TC by 0.377 mmol/L,and LDL-C by 0.329 mmol/L. Conclusions Serum level of TC associated with polymorphism of ApoE gene carrier in boys, with the lowest levels of TC, LDL-C and ApoB in those with allele E2.