线粒体DNA3316、3394等4个突变位点与2型糖尿病的关系研究

目的:探讨DNA tRNA Leu(UUR)基因及ND-1基因3316 G/A、3394 T/C等4个突变位点与2型糖尿病的关系。方法:对236例海南地区2型糖尿病患者和252例健康对照者进行空腹血糖测定并采用聚合酶链式反应—限制性核酸内切酶片段长度多态性(PCR-RFLP)的分析方法进行mtDNA的3243、3316、3394、和3593共4个位点进行突变筛选,并采用DNA测序方法确证。结果:实验组空腹血糖(9.37±3.01)mmol/L与健康对照组(4.96±0.76)mmol/L差异有统计学意义(P<0.05);实验组检出3316(G→A)突变8例,3394(T→C)突变3例;健康对照组未发现上述突变;突变检测结果与测序一致。两组间3316(G→A)突变率差异有统计学意义(P<0.05)。结论:线粒体DNAtRNALeu(UUR)基因及ND-1基因3316、3394位点的基因突变,尤其是3316位点(G→A)突变可能与某些核基因或环境因素协同促进了2型糖尿病的发生。

Study on relationship between point mutations of mitochondrial gene and type 2 diabetes mellitus

Objective: To explore the relationship between various mitochondrial DNA tRNA Leu(UUR)gene / ND-1 gene mutations and type 2 diabetes.Methods: Case-control study was designed.Fasting blood glucose levels in 236 patients with type 2 diabetes mellitus(study group) and 252 healthy subjects(control group)were determined respectively.Polymerase chain reaction restriction fragment length polymorphism(PCR-RFLP) analysis was used first to screen point mutations of mtDNA at positions of 3243,3316,3394,and 3593;DNA sequencing was adopted to confirm the mutations followed;all the mutations were analyzed by PRIMER and NCBI BLAST softwares at last.Results : The levels of fasting blood glucose in study group and control group were(9.37±3.01) and(4.96±0.76) respectively,compared with them,there was significant difference(P<0.05).In study group,there were 8 carriers(3.4%) of 3316 G→A(Ala→Thr) mutation,3 carriers(1.3%) of 3394 T→C(Tyr→His) mutation with type 2 diabetes mellitus.In control group,no mutation was found.There was significant difference between the two groups for 3316 G→A mutation frequencies(P<0.05).Conclusion: Mutations at np 3316,in DNA ND-1 gene,and at np3394 may play a certain role with the coactions of some nuclear DNA or /and environmental factors for the incidence of type 2 diabetes mellitus.