INS and type 2 diabetes mellitus: Serum insulin levels in T2D patients associated also with THADA tv5 (p < 0.01) and TSPAN8 levels (p < 0.05), tended to correlate negatively with KCNQ1 tv1 levels (p = 0.06), while, in CTRF+ subjects, associated with IGF2BP2 tv7 levels (p < 0.05).