Among other mechanisms, elevated activity and/or expression of arginase i.e., the L-arginine:ureahydrolase including arginase-I (Arg-I) and arginase-II (Arg–II) isoenzyme, has been shown to cause eNOS-uncoupling, resulting in increased oxidative stress in aging and age-associated cardiovascular diseases including atherosclerosis and type 2 diabetic vascular dysfunctions (Yepuri et al., 2012; Li and Förstermann, 2013). The gene discussed is NOS3; the disease is cardiovascular disorder.