It has been suggested that the cell-type-specific expression or co-expression of ACE2 and proteases, as the mediators of SARS-CoV-2 viral entry, may affect susceptibility, severity, and transmissibility of COVID-19, as well as certain aspects of the epidemiology, and clinical course of the disease (Channappanavar et al., 2017; Muus et al., 2021). This evidence concerns the gene ACE2 and COVID-19.