KCNJ8 and ABCC9: Mutations in both KCNJ8 (Kir6.1) and ABCC9 (SUR2A) genes can result in a gain-of-function effect in the IK-ATP channel, leading to abnormal action potential characteristics associated with BrS or short QT syndrome phenotypes [72]. The gene discussed is KCNJ8; the disease is Familial short QT syndrome.