HNF4A and congenital isolated hyperinsulinism: The genetic basis of CHI involves mutations in eight key genes (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, HNF4A and UCP2) (10,11,12,13,14,15,16,17) identified so far, which regulate insulin secretion from the β-cells.