Abstract
Previous work suggests that mitochondrial DNA (mtDNA) derived from the maternal genome has a close affinity with type 2 diabetes. This would support a familial pattern for type 2 diabetes. Thereby, we analyzed complete mtDNA genomes from two families, A and B, from Southwest China that demonstrated maternally inherited type 2 diabetes. Our data support that mtDNA lineages from families A and B belong to haplogroups A4 and D4h1, respectively. This suggests that maternally inherited type 2 diabetes with similar penetrances can arise in Chinese individuals with strikingly different maternal genetic backgrounds. Two private coding region mutations (G13759A in MT-ND5 and G15930A in tRNA-Thr) were identified in family B. Further evolutionary and phylogenetic analyses suggest that both these mutations have multiple origins and are unlikely to be disease causing.
Declaration of interest
The authors declare that they have no conflicts of interest. This work was supported by grants from the National Natural Science Foundation of China (No. 81260135), the training fund of Young and Middle-Aged Academic Technology leaders in Yunnan Province (No. 2011CI045) and the fund of medical leader in Yunnan Province (No. D-201217). The Youth Innovation Promotion Association, Chinese Academy of Sciences provided support to M. -S. P.
Supplementary material available online
Supplementary Appendix A–E.