Melatonin has been shown to increase antioxidant enzymes and decrease ROS as seen by increases in SOD and catalase activity, and decreases in erythrocyte malondialdehyde levels in treated older adults with HTN and elderly adults with type II diabetes (Kedziora‐Kornatowska et al., 2008, 2009). The gene discussed is CAT; the disease is type 2 diabetes mellitus.