糖尿病分子生物学和遗传学

　　【摘要】 目的 探讨线粒体基因tRNALeu(UUR)基因A3243G突变糖尿病患者的临床特征。 方法 选取疑似线粒体基因突变糖尿病患者12例，采外周血提取DNA，检测mtDNA3243A→G点突变情况。 结果 共4例患者携带mtDNA3243A→G点突变，均存在线粒体基因突变糖尿病的典型临床表现，即起病年龄早[(29.75±4.64)岁]、体型消瘦[BMI(17.00±1.04)kg/m2]、伴严重双耳听力损害、胰岛β细胞分泌功能降低[FC-P(0.46±0.22)ng/ml，2 hC-P(1.23±0.62)ng/ml]及无明显的母系遗传史。在测定骨密度的3例患者中，2例骨质疏松，1例骨密度降低。 结论 线粒体基因突变糖尿病患者存在一定的隐匿性，对消瘦、耳聋的年轻患者进行线粒体基因突变筛查及骨代谢评估，有利于及时诊治线粒体基因突变糖尿病患者，防止并发症发生。

　　【关键词】线粒体基因突变糖尿病;骨质疏松;骨密度

　　【Abstract】 Objective To investigate the clinical characteristics of diabetic patients with mitochondrial DNA (mtDNA) mt3243A→G mutation. Methods Twelve suspected mitochondrial diabetic patients were recruited. The gene fragment was produced by PCR, and mutation was detected by direct sequencing. Results Four of twelve suspected mtDNA diabetic patients carried mt3243A→G mutation. All four patients had classic clinical features of mitochondrial DNA diabetes, including diabetes in early age, low BMI, deafness, and impaired β cell function, but without significant maternal inheritance. Furthermore, two of three patients were diagnosed as severe osteoporosis, and one was diagnosed as reduced bone mineral density. Conclusion Screening the mitochondrial gene mutation in the diabetes patients with lean and deafness can improve the diagnostic rate. Clinicians should pay attention to abnormal bone metabolism in the patients with mitochondrial diabetes.

　　【Key words】 Mitochondrial gene mutation diabetes;Osteoporosis;Bone density