Polymorphisms in other host genes, such as TMPRSS2, DPP4, interferon-lambda-3, tolloid like-1, discoidin domain receptor 1 and HLA-DRB1*08, may also contribute to the susceptibility and severity of COVID-19 (Irham et al., 2020; Senapati et al., 2020; Agwa et al., 2021; Amoroso et al., 2021). This evidence concerns the gene TMPRSS2 and COVID-19.