早老素-1基因启动子区-48C/T位点多态性与LOAD的遗传相关性

The genetic association between the -48C/T polymorphism in the presenilin-1 promoter and the risk of LOAD

目的 研究早老素 - 1基因启动子区 - 4 8C/T位点的多态性与迟发性AD(LOAD)的相关性。方法 用常规方法从人外周血白细胞中抽提基因组DNA ,PCR扩增出包含 - 4 8C/T多态性位点的基因片段 ,利用PCR -RFLP技术对 -4 8C/T多态性位点进行基因分型 ,χ2 检验分析 - 4 8C/T多态性位点基因型分布和等位基因频率。结果 以 33例AD病例和32例对照样品的外周血白细胞基因组DNA为模板 ,PCR扩增出了长度为 344bp的包含 - 4 8C/T多态性位点的基因片段。基因分型结果表明 ,33例散发型AD的C和T等位基因频率分别为 4 7%和 5 3% ,C/T和T/T基因型频率分别为 94 %和 6 %。而 32例正常对照的C和T等位基因频率分别为 4 8%和 5 2 % ,C/T和T/T基因型频率分别为 97%和 3%。χ2 检验结果显示 ,病例 -对照样品间C和T等位基因频率及C/C、C/T和T/T基因型的分布均无显著性差异 (χ2 值分别为 0 4 4 3和 0 318,P>0 .0 5 )。结论 在我们研究的群体中 ,早老素 - 1基因启动子区 - 4 8C/T位点的多态性与LOAD无显著的遗传相关性。

Objective: To evaluate the asociation between -48C/T polymorphism in presenilin-1 promoter and the risk of LOAD. Methods: Genomic DNAs from human peripheral white blood cells were extracted by routine methods, and the gene fragment containing -48C/T polymorphism was obtained by PCR. The -48C/T polymorphism sites were genotyped with PCR-RFLP and its genotypic distribution and allelic frequency calculated by χ 2 test. Results: The 344 bp gene fragments containing -48C/T polymorphism site were obtained by PCR based on human peripheral white blood cells genomic DNA templates of 33 AD cases and 32 controls. Genotyping results show that the C and T allelic frequencies of 33 sporadic cases were 47% and 53%, respectively, and the C/T and T/T genotypic frequencies were 94% and 6%, respectively. However, the C and T allelic frequencies of 32 controls were 48% and 52%, and the C/T and T/T genotypic frequencies were 97% and 3%, fespectively. χ 2 test results indicated that there were no significant differences in C and T allelic genes frequencies and in C/C?C/Tand T/T genotypes distribution between case-control populations (χ 2 values were 0.443 and 0.318, P>0.05,respectively). Conclusion: No evident genetic association between -48C/T polymorphism in presenilin-1 gene promoter and LOAD were found in our population-based sample.