VKORC1 and atrial fibrillation: Greater bleeding risk among variant carriers in CYP2C9 and VKORC1 was clearly demonstrated in the Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48 (ENGAGE AF-TIMI 48) clinical trial that compared edoxaban vs. warfarin [45].