线粒体DNA3243、3316点突变与2型糖尿病

Mitochondrial DNA 3243,3316 point mutations and type 2 diabetes mellitus

目的 研究2型糖尿病患者中线粒体t RNAL eu( UUR)基因32 4 3A/ G突变和NADH脱氢酶亚单位1基因(ND1)基因3316 G/ A突变的发生频率及其与2型糖尿病的相关性。方法 应用聚合酶链反应及限制性片段长度多态性技术检测2 2 5例中国云南2型糖尿病患者和195名无糖尿病家族史的健康对照者有无32 4 3A/ G突变和3316 G/ A突变,并经DNA直接测序确证。结果 2型糖尿病患者中3316 G/ A突变者5例(2 .2 2 % ) ,195例对照者中突变者2例(1.0 3% ) ,突变发生率在两组间差异无统计学意义(P=0 .4 5 76 ) ;两组中无线粒体32 4 3A/ G突变。结论 线粒体t RNALeu( UUR) 基因32 4 3A/ G突变在中国云南2型糖尿病人群中发生频率低,可能不是云南人群中2型糖尿病的常见病因。线粒体ND1基因3316 G/ A突变可能仅为人群中线粒体基因组的正常多态。其他的遗传、环境及子宫内因素需要进一步研究。

Objective To investigate the prevalence of mitochondrial DNA (mtDNA) mutation at position 3243(A/G) and 3316(G/A) in Chinese patients with type 2 diabetes mellitus. Methods Two hundred and twenty-five unrelated Chinese patients with type 2 diabetes and 195 nondiabetic control individuals without family history of diabetes in Yunnan were examined. The presence of mt 3243 and 3316 mutations was determined by polymerase chain reaction amplification and restriction fragment length polymorphism (PCR/RFLP). Finally, mutant mtDNA was confirmed by DNA sequencing. Results The mitochondrial DNA mutation at position 3316 was found in 5 of 225 (2.22%) patients with type 2 diabetes, and this mutation was found in 2 of 195 (1.03%) control individuals. There was no significant difference in respect to the frequency of the mutation between patients and controls. The mitochondrial DNA mutation at position 3243 was not found in any of the patients and controls. Conclusion The results suggest that the prevalence of the mitochondrial tRNA Leu(UUR) gene at position 3243(A/G) mutation is so low that it may not be a major cause of type 2 diabetes mellitus in patients of Yunnan, China, and the mitochondrial ND1 gene at position 3316(G/A) mutation may be a polymorphism unrelated to diabetes in Chinese. The role of other genetic, environmental and intrauterine factors needs further investigation.