Mutations in hepatocyte nuclear factor 4 alpha, (HNF4A, MODY1), glucokinase (GCK, MODY2), hepatocyte nuclear factor 1 alpha (HNF1A, MODY3) result in most common forms of MODY (Shields et al., 2010; Pihoker et al., 2013). The gene discussed is HNF4A; the disease is MODY.