Study on the mtDNA tRNALeu(UUR) mutation in diabetics with onset age less than 45 years / 中国糖尿病杂志

ABSTRACT

Objective To investigate the prevalence of mtDNA A3243G mutation in the early onset diabetics in Tianjin for exploring the relationship between mtDNA mutation and diabetes. Methods 348 kinship-free diabetics whose ages at onset were less than 45y were randomly recruited, with 207 control subjects. The PCR-RFLP and cloning techniques were applied to screen the A to G substitution at nucleotide 3243 of mtDNA tRNALEU（UUR）. Meanwhile, the clinical and genetic analysis was done from one pedigree. Results We detected two diabetics harboring the well-known a3243g mutation with the mutation frequency of 0.6%. While the mutation frequency in diabetics with （positive） family history was 1.2%, and zero in the control subject. The proband showed a typical （picture） of mitochondrial diabetes mellitus, while the other family members harboring the same （mutation） had heterogeneous presentation. Conclusion The prevalence of mtDNA A3243G mutation in early onset diabetes of Tianjin is low, but relatively higher in diabetes complicated with other （symptoms） of mitochondrial disease. Furthermore, its heterogeneity would decrease with aging in （mitotic） tissue