On the other hand, the non-COVID-19 ARDS patients demonstrated abnormal ET-1 handling [A:V ET-1 ratio 1.06 (0.93–1.20)], while the non-COVID-19 non-ARDS group showed normal ET-1 handling [0.79 (0.52–1.11)]. The gene discussed is EDN1; the disease is COVID-19.