Novel mutations found in mitochondrial diabetes in Chinese Han population

Abstract Mitochondria provide cells with most of the energy in the form of ATP. Mutations in mitochondrial DNA (mtDNA) are associated with type 2 diabetes mellitus (T2DM) because ATP plays a critical role in the production and the release of insulin. To systematically determine mutant loci and to investigate their association with T2DM in Chinese Han population, 17 commonly reported mutant loci were screened in 236 cases of T2DM and 240 normal controls by PCR-RFLP, allele-specific PCR (AS-PCR) and DNA sequencing methods. Biological softwares were used to analyze the secondary structure of DNA, RNA and the corresponding proteins for missense mutations. Sixteen mutant loci were detected in total, of which five were novel, GenBank accession nos. were P  = 0.001, OR = 3.944, 95% CI 1.671–9.306; ND4: P  = 0.010, OR = 5.818, 95% CI 1.275–26.537). No significant association was observed between the two groups for 5178A/C polymorphisms ( P  = 0.418). Our study suggested that T3394C and A12026G might be associated with T2DM in Chinese Han population, and T2DM with mtDNA variant should be considered mitochondrial diabetes.