胰岛素样生长因子I基因启动子区CA重复序列多态性与2型糖尿病的相关性

Association of CA repeats polymorphism in the promoter region of the insulin-like growth factor- I gene with type 2 diabetes

目的 研究胰岛素样生长因子Ⅰ（IGF-Ⅰ）基因启动子区CA重复序列多态性与2型糖尿病发病的相关性.方法 采用口服葡萄糖耐量试验筛选出性别、年龄匹配的新诊2型糖尿病患者147例,正常糖耐量者159例,将抽提的基因组DNA应用聚合酶链反应扩增,再通过选择不同长度的纯合子样本测序确定CA重复的次数,以确定等位基因,分析其与2型糖尿病发病的相关性.结果 CA重复各基因型分布在2型糖尿病组及正常糖耐量组无显著差异.携带≥（CA）20等位基因的受试者较不携带该种等位基因的受试者具有显著低的血尿酸[（4.18±1.25对4.63±1.36）mg/dl,P=0.03].结论 携带CA重复次数≥20的等位基因可能是2型糖尿病的保护因子.

Objective To investigate the association of CA repeats polymorphism in the promoter region of human IGF-I gene with type 2 diabetes in narthen Han nationality. Methods Gender-age matched subjects with type 2 diabetes and normal glucose tolerance （NGT） were enrolled for this study, 147 subjects in type 2 diabetes group and 159 subjects in NGT group. Genomic DNA was extracted by standard methods. PCR, Genescan,Genotyper, and direct sequencing were conducted to screen CA repeats polymorphism in the promoter region of the human IGF-I gene. Results No significant association was observed between any （ CA）, repeat genotype and type 2 diabetes. A lowered serum uric acid was seen in genotypes that included alleles with larger than （CA） 20 repeats [（4.18 ± 1.25 vs 4.63 ± 1.36） mg/dl, P = 0.03]. Conclusion Alleles with larger than （CA） 20 repeats may be a protective factor for type 2 diabetes.