ACE2 and type 2 diabetes mellitus: In regard to future directions, it will be interesting to follow the story of both the ACE2 enzyme and the transmembrane serine protease 2 (TMPRSS2) gene polymorphisms to observe whether there are any genotype alterations that may be associated with the development of the accelerated natural history in MetS, T2DM and COVID-19 specifically in different global subpopulations [89].