The Kots group [124] evaluated the associations of circulating levels of stable metabolites of nitric oxide, nitrate, nitrite (NOx), and endothelin-1, as well as the endothelin-1/NOx ratio, with blood pressure in 177 asymptomatic subjects without signs of coronary atherosclerosis, and in 457 patients with the presence of coronary lesions and suspected to have coronary heart disease with or without coronary lesions confirmed by coronary angiography. The gene discussed is EDN1; the disease is coronary artery disorder.