Early studies after the onset of the SARS-CoV-2 pandemic provided the initial evidence that the OSNs do not express SARS-CoV-2 entry receptors, including ACE2 and TMPRSS2, and therefore, infection of these cells may not be the cause of the loss of the sense of smell associated with SARS-CoV-2 infection [51,53,54,64]. The gene discussed is ACE2; the disease is infection.