The small GTPase RhoA and the downstream Rho kinase (ROCK) regulate several cell functions and pathological processes in the vascular system that contribute to the age‐dependent risk of cardiovascular disease, including endothelial dysfunction, excessive permeability, inflammation, impaired angiogenesis, abnormal vasoconstriction, decreased nitric oxide production and apoptosis. The gene discussed is RHOA; the disease is cardiovascular disorder.