Nearly 90% of MODY cases are caused by variants in glucokinase (GCK, MODY2), hepatocyte nuclear factor 1-alpha (HNF1A, MODY3), or hepatocyte nuclear factor 4-alpha (HNF4A, MODY1), although the distribution of subtypes varies across populations [9]. The gene discussed is HNF1A; the disease is MODY.