TCF7L2 and type 2 diabetes mellitus: Subsequently, the advent of genome-wide association studies—focused on SNP recognition—followed by meta-analyses, led to the identification of hundreds of genes associated to T2D (TCF7L2, SLC30A8, HHEX, ADAMTS9, CDC123/CAMK1D, CDKAL1, CDKN2A/B, IGF2BP2, JAZF1, NOTCH2, RBMS1, THADA, TSPAN8/LGR5, PPARG, etc.)[28,29,30,31,32,33,34].