Mitochondrial DNA atlas reveals physiopathology of type 2 diabetes

Type 2 diabetes (T2D), one of the most common metabolic diseases, is the result of insulin resistance or impaired insulin secretion by mitochondrial dysfunctions. Mitochondrial DNA (mtDNA) polymorphisms play an important role in physiological and pathological characteristics of T2D, however, their mechanism is poorly understood. To directly identify candidate mtDNA variants associated with T2D at the genome-wide level, we constructed forty libraries from ten patients with T2D and thirty control individuals for deep sequencing. We characterized their mtDNA atlas, and analyzed their single nucleotide polymorphisms (MtSNPs), insertions and deletions (InDels), and screened potential mtDNA mutation sites associated with T2D. We found ten mtDNA polymorphisms at nucleotides 489T > C, 3105AC > A, 3107N > C, 8701A > G, 9540T > C, 10398A > G, 10400C > T, 10873T > C, 12705C > T and 14783T > C that showed a significant difference between patients and control subjects. Therefore, our results characterize mtDNA atlas of patients with T2D, and further demonstrate that mtDNA variants are participated in the pathophysiology of T2D and other diseases. In addition, mtDNA variants may be candidate molecular biomarkers of T2D, and they may be valuable for early diagnosis of T2D in the future. Overall design: To directly identify candidate mtDNA variants associated with T2D at the genome-wide level, we constructed forty libraries from ten patients with T2D and thirty control individuals for deep sequencing. We characterized their mtDNA atlas, and analyzed their single nucleotide polymorphisms (MtSNPs), insertions and deletions (InDels), and screened potential mtDNA mutation sites associated with T2D.