ACE2 is the target of SARS-CoV-2 (15), and elevated ACE2 as found in patients characterized by a (preexisting) proinflammatory gut microbiome creates conditions favorable for infection by coronaviruses (16) like SARS-CoV-2 of the gut epithelium, from which it can further spread through the body (17). This evidence concerns the gene ACE2 and infection.