Other possible mechanisms behind hypertension are thought to be renin–angiotensin and the sympathetic nervous system [63,64], oxidative stress [65], circulating catecholamine levels [66], beta-adrenergic receptors [66], Na+/K+ ATPase [66], and endothelial factors [66], as well as renal dysfunction [67]. The gene discussed is REN; the disease is Abnormal renal physiology.