Atrial Fibrillation, Familial, 9, is also known as atfb9. An important gene associated with Atrial Fibrillation, Familial, 9 is KCNJ2 (Potassium Inwardly Rectifying Channel Subfamily J Member 2). Affiliated tissues include heart and heart-atrium, and related phenotypes are palpitations and paroxysmal atrial fibrillation