FMO5 and Hypertension: Recent genome-wide association studies (GWAS) [5] in search of hypertension risk genes point towards NADPH oxidases (Nox), the only known enzyme family dedicated to ROS formation, in particular the genes Nox4 and Nox5. This matches preclinical studies, excluding other vascular NOX isoforms, i.e., NOX1 and NOX2, for causing hypertension, unless animals are infused with pro-hypertensive agents [6–8].