KCNH2 and short QT syndrome: Due to its crucial role in the cardiac AP, impairment of hERG channel function can lead to severe cardiac disorders, manifested by altered QT intervals (the time required for depolarization and repolarization of the ventricles during a single cardiac cycle).2 For instance, inherited loss-of-function mutations in hERG can cause long QT syndrome which predisposes individuals to life threatening TdP arrhythmia.14 Analogously, inherited gain-of-function mutations are associated with short QT syndrome, a rare genetic anomaly, but also associated with an increased sudden death risk.15