Persistent congenital hyperinsulinemic hypoglycemia (CHH) can be caused by mutations in the ABCC8/KCNJ11, GLUD1, HADH, GCK, HNF4A, HNF1A, SLC16A1 and UCP2 genes (1,2). Here, KCNJ11 is linked to cartilage-hair hypoplasia.