108例汉族人群let-7a基因调控区多态性与糖尿病肾病的相关性分析

Correlation of single nucleotide polymorphism of let-7a gene regulatory region with diabetic nephropathy in 108 cases of Chinese Han population

目的探寻循环miRNA let-7a与糖尿病肾病(diabetic nephropathy,DN)的关系,分析并评估let-7a调控区域单核甘酸多态性(single nucleotide polymorphism,SNP)对DN疾病的易感性。方法 Real-time PCR检测病例组及对照组中let-7a的表达水平。生物信息学方法预测并筛选3个位于let-7a前体(let-7a-2)启动子调控区域标签SNP(Tag SNP),采用聚合酶链式反应-限制性片段长度多态性(RFLP-PCR)法对108例糖尿病肾病(DN)、104例糖尿病(DM)患者及62例健康人对照(CON)3个SNP进行基因分型。结果 Real-time PCR结果显示let-7a在DN、DM、CON三组中表达水平有显著差异(P<0.05)。let-7a-2基因调控区域rs1143770多态位点的CT杂合子基因型在DN、DM、CON三组间有显著差异(P<0.05),且在DM组和DN组CT+TT两基因型均依次较CON组显著升高(P=0.049;P=0.001)。结论 miRNA let-7a可能参与调控DN疾病,其启动子调控区rs1143770多态与中国汉族人群糖尿病肾病相关,可能是个潜在的功能位点。

Objective To explore the relationship between the circulating miRNA let-7a and diabetic nephropathy （DN）, and to evaluate the susceptibility of the single nucleotide polymorphism （SNP） of let-7a regulatory region to DN. Methods Real-time PCR was carried out to detect the expression level of let-7a in the patients and control groups. We used bioinformatics methods to predict and filter out 3 Tag SNPs in let-7a gene promoter regulatory region. Polymerase chain reaction-restriction fragment length polymorphism （RFLP-PCR） was executed to genotype 108 DN patients （DN group） , 104 patients with diabetes （DM group） and 62 cases of healthy controls （CON group）. Results Real-time PCR results showed that the expression level of let-7a were significantly different among the DN, DM, CON groups （P〈0.05）. A variant rs1143770 was found in let-7a-2 regulatory region and the distributions of CT genotypes were significantly different among the 3 groups （P〈0.05）. The CT＋TT genotype frequencies were significantly higher in the DM and DN groups than in the CON group （P=0.049, P=0.001）. Conclusion miRNA let-7a may participate in the regulation of DN occurrence, and rs1143770 in let-7a-2 regulatory region is significantly associated with the increased risk of DN in Chinese Han population and might be regarded as a potential functionol site.