The ANK2 gene encodes Ankyrin-2, a protein belonging to the Ankyrin family. Ankyrins are involved in the localization of membrane proteins to their correct positions in the cell membrane. They also play a role in membrane stabilization by anchoring these proteins to the underlying spectrin-actin cytoskeleton. ANK2 specifically targets and stabilizes ion channels such as the Na+/K+ ATPase and the Na+/Ca2+ exchanger in cardiomyocyte cells. By carrying out its function, ANK2 plays a role in the regulation of heart rate by cardiac conduction.
Mutations in the ANK2 gene can thus have severe cardiac consequences. The gene is implicated in Long QT syndrome 4 (LQT4) as well as the milder condition of Ankyrin-B-related Cardiac Arrhythmia. While both conditions can result in sinus bradycardia, sinus node dysfunction and sudden cardiac death, LQT4 is characterized by prolonged QT intervals in electrocardiogram studies, which are not seen in Ankyrin-B-related Cardiac Arrhythmia.