As reported previously3, these associations were due in part to (presumably undiagnosed) MODY cases within ProDiGY: 62 (2.1%) of youth-onset T2D cases carried variants in these genes classified as pathogenic or likely pathogenic, the majority within HNF1A (32 cases) and GCK (16 cases). The gene discussed is HNF1A; the disease is type 2 diabetes mellitus.