TCF7L2 and type 2 diabetes mellitus: Recently, a total of nine candidate genes for T2DM have been identified and replicated in humans through multiple genome-wide association studies of common variants by using high-density SNP mapping approaches: Cdkal (score 0),Cdkn2a (score 0)/Cdkn2b (1.925, 1165/15277), Fto (1.798, 1364/15277), Hhex (1.213, 2456/15277), Igf2bp2 (0.855, 3555/15277), Kcnj11 (2, 1056/15277), Pparg (2.528, 500/15277), Slc30a8 (0.076, 8056/15277), and Tcf7l2 (2.192, 811/15277) [5-11].