ABCC8 and congenital isolated hyperinsulinism: Most commonly, CHI is the consequence of loss-of-function (LOF) mutations in the ABCC8 (SUR1) and KCNJ11 (Kir6.2) genes located on chromosome 11p15.1, which encode the adenosine triphosphate (ATP)-sensitive potassium channel (KATP) of pancreatic β cells [4].