Decreased clearance of ET-1 has been described in pulmonary hypertension, pulmonary fibrosis, coronary disease, asthma, ARDS, septic shock, and collagen vascular disorders such as systemic sclerosis and systemic lupus erythematosus, among others [16,17,18,19,20,21,22,23,24,25,26,27]. The gene discussed is EDN1; the disease is pulmonary arterial hypertension.