Heterozygous mutations in HNF6 cause juvenile-to-adult-onset diabetes characterized by defective insulin secretion, whereas complete loss of HNF6 leads to syndromic diabetes.38 Pancreatic progenitors generated from ONECUT1−/− and the 2 disease-causing variants, ONECUT1-p.E231X and ONECUT1-p.E231D, hPSCs showed a decreased expression of the key β-cell marker NKX6.1, along with NKX6.2 and NKX2.2, due to decreased occupancy of their enhancers by ONECUT1 leading to a reduction in their activity. The gene discussed is ONECUT1; the disease is diabetes mellitus.