Common variants in several neonatal diabetes mellitus and maturity-onset diabetes of the young (MODY) [e.g., potassium inwardly rectifying channel, subfamily J, member 11 (kcnj11), glucokinase (gck), hepatocyte nuclear factor 4 alpha (hnf1α), and hnf1β] are recognized as type 2 diabetes susceptibility variants 6 and 43 (Bonnefond et al., 2010). The gene discussed is GCK; the disease is type 2 diabetes mellitus.