In the Assessment of Direct oral Anticoagulants in Geriatrics (ADAGE) study conducted by our group in patients aged ≥80 years with AF receiving rivaroxaban or apixaban, we evidenced important (>50%) coefficients of variation (CVs) in both maximal (Cmax) and minimal plasma concentrations of both anti-FXa inhibitors [17]. The gene discussed is F10; the disease is atrial fibrillation.