INS and type 2 diabetes mellitus: The non-pathogenic mtDNA T16189C variant, a polymorphism located in the mitochondrial D-loop region that regulate mtDNA replication is associated with increased oxidative damage, altered antioxidative status in T2DM patients, metabolic syndrome, higher fasting insulin concentration, insulin resistance index, and lacunar cerebral infarction in the Asian population [112,113,114,115,116].