Past linkage studies have identified those genes associated with the most prominent T2DM effects, i.e., TCFL7, PPARG, and KCNJ11. More recently genome-wide association studies (GWAS) have confirmed previous reports and uncovered dozens of new genetic variants associated with an increased risk of T2DM [10–15]. Here, KCNJ11 is linked to type 2 diabetes mellitus.