A majority of genes associated with type 2 diabetes from this meta-analysis (ADCY5, CDKAL1, CDKN2A/B, HHEX, IGF2BP2, SLC30A8, TCF7L2 and KCNQ1) are involved in pancreatic beta cell function, while two are implicated in insulin sensitivity (PPARG) and adiposity (FTO). The gene discussed is TCF7L2; the disease is type 2 diabetes mellitus.