线粒体tRNA^(Leu(UUR))A3243G基因突变与2型糖尿病的相关研究

Study on mitochondrial DNA gene tRNA Leu(UUR)A3243G mutation in type 2 diabetes mellitus

目的 探讨线粒体 t RNALeu( UUR) 32 4 3A→ G突变在中国人 2型糖尿病 (type2 diabetes melli-tus,DM2 )人群中的发生率及其临床特征。方法 随机抽取无血缘关系的 DM2患者 4 2 8例及正常对照 188名 ,采用PCR/ Apa 酶切法进行线粒体基因 t RNAL eu( UUR) 32 4 3A→G突变检测。结果 在 DM2组中发现 2例该基因突变患者 ,在 2例患者的家系中又检出 3例阳性患者。其中例 1及其儿子除患糖尿病外 ,还呈线粒体肌脑病伴乳酸酸中毒及中风样发作综合征表现。基因突变患者的临床特点主要为糖尿病伴或不伴耳聋 ,有家族史 ,呈母系遗传。结论 线粒体基因 t RNAL eu( UUR) 32 4 3A→G突变性糖尿病在中国 DM2人群中的发病率约为 0 .4 7% ,突变患者的临床表型呈一定的异质性。

Objective To explore the prevalence and the clinical characteristics of mitochondrial gene mutation A3243G (mt tRNA Leu(UUR)3243A→G) in patients with type 2 diabetes mellitus (DM2) in China. Methods Four hundred and twenty-eight cases of DM2 patients were selected randomly. One hundred and eighty-eight individuals were healthy controls.The mutation was assayed by PCR-restriction fragment length polymorphism technique.The target fragments of PCR were digested with restriction endonuclease ApaⅠ. Results mt tRNA Leu(UUR)3243A→G gene mutation was found in 2 of 428 patients with DM2,but not found in the controls. Further investigation of the relatives of the 2 patients' families revealed that 3 members were the carriers of mt tRNA A3243G gene mutation and the patients with diabetes. In addition, one proband and her son were characterized with the syndrome of mitochondrial encephalomyopathy with lactic acidosis. The diabetes of these patients is frequently accompanied by hearing impairment or deafness with maternal inheritance. Conclusion The prevalence of the mitochondrial gene A3243G mutation is 0.47% in DM2 patients in China. The data acquired in this study suggest that the clinical phenotype of these patients with A3243G should be heterogeneous.