应用PCR-RFLP和测序对一个2型糖尿病家系的线粒体DNA G7444A的突变进行检测, 并分析其临床资料的特点。结果发现, 27例家系成员中, 11例母系亲属均存在线粒体DNA G7444A突变, 而配偶及父系亲属中未发现该突变。11例突变者中确诊为2型糖尿病患者5例, 糖耐量受损1例, 均表现为乳酸和血糖增高。因此, 线粒体DNA G7444A突变是该家系中糖尿病的遗传易感因素, 是导致2型糖尿病的一个新的突变位点。

Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and direct sequencing were applied to detect a new point mutation of nt7444G→A in the mitochondrial DNA in a type 2 diabetes mellitus family. The related clinical data were also collected and analyzed. mtDNA G7444A mutation in the cytochrome c oxidase I (COI) gene was found in 11 of 27 cases, all of whom were from the maternal side. Among them, 5 were confirmed to have type 2 diabetes mellitus, and one had impaired glucose tolerance. We conclude that the novel point mutation of mtDNA G7444A may be an independent factor associated with type 2 diabetes mellitus.