In addition, the co-expression of cleaving enzymes, such as the transmembrane serine protease 2 (TMPRSS2), as well as the proximity to the systemic network, are factors favoring the efficiency of viral infection; these factors thus allow SARS-CoV-2 to optimize not only its cellular entry, but also the production of new virions leading to inflammatory mechanisms and cytopathic destruction [14,15,16,17,18]. The gene discussed is TMPRSS2; the disease is viral infectious disease.