The mitochondrial tRNA^Gly T10003C mutation may not be associated with diabetes mellitus

Mitochondrial DNA (mtDNA) mutations have long been proposed to play important roles in the pathogenesis of diabetes mellitus (DM). A large proportion of these mutations are localized at the mt-tRNA genes. Owing to its high mutation rate, a growing number of mt-tRNA mutations have been reported; however some of them are neutral genetic polymorphisms and will not result in the alteration of the mitochondrial function responsible for DM. In this study, we reassessed a recent reported “pathogenic” mutation, tRNA^Gly T10003C, in a clinical manifestation of DM. We first performed the conservation assessment of this mutation between different species. Moreover, the bioinformatics analysis was used to predict the secondary structure of mt-tRNA^Gly in wild type version and the mutant carrying the T10003C mutation. We also screened the presence of the T10003C mutation in 500 unrelated DM patients and 300 healthy controls. We noticed that the T10003C mutation was not very conserved and did not cause the secondary structure change of mt-tRNA^Gly. Moreover, this mutation was absent in the 500 unrelated DM patients and controls, suggesting that this mutation may be a rare event in the human population. In conclusion, the current study showed no association between the T10003C mutation and DM in humans.