A mutation in the genes coding for either subunit prevents K(ATP) channels from being trafficked normally to the plasma membrane or alters their sensitivity to adenine nucleotides, leading to persistent hyperinsulinemic hypoglycemia of infancy (PHHI) in humans, a condition characterized by high insulin secretion that occurs even when blood glucose is low [25–27]. This evidence concerns the gene INS and congenital isolated hyperinsulinism.