HNF1A and diabetes mellitus: However, HNF1α+/− mice do not develop diabetes (Pontoglio et al., 1998) and HNF1α−/− mice show growth retardation, impaired insulin release, and aerobic glucose metabolism, but unlike MODY3 patients suffer from other renal and kidney complications due to the pleiotropic effect of complete loss of HNF1α (Lee et al., 1998; Pontoglio et al., 1996, 1998; Servitja et al., 2009).