Low levels of ACE-2 were reported in primary respiratory pathologies such as pulmonary hypertension, atherosclerosis (Tikellis and Thomas, 2012), and metabolic pathologies such as obesity (Iannelli et al., 2020) and DMT2, where the decreased ACE-2 activity was observed in the GI (Obukhov et al., 2020). The gene discussed is ACE2; the disease is obesity due to melanocortin 4 receptor deficiency.