Furthermore, the acute COVID-19 disease uses angiotensin converting enzyme 2 (ACE2), expressed by epithelial cells of the lung, intestine, and kidney for cellular internalization; in DM patients, increased expression of ACE2 enzyme has been shown, suggesting a greater susceptibility [31], as well as a consensual reduced activity of the T lymphocytes [32]. The gene discussed is ACE2; the disease is diabetes mellitus.