For example, Hou et al., based on ananalysis of ~ 81,000 human genomes, investigated the association between thepolymorphism of the ACE2 and TMPRSS2 genes(two key host factors of SARS-CoV-2) and susceptibility to COVID-19.ACE2 polymorphisms (p.)(e.g., p.Arg514Gly in theAfrican/African American population) were found to be associated with thecardiovascular and pulmonary diseases through altered angiotensinogen–ACE2 interactions. Here, ACE2 is linked to lung disorder.