The second ongoing trial (NCT04411563) involved the assessment of the DNA methylation status of ACE2, TMPRSS2, and PARP (interleukin activator in the cytokine storm) genes in an attempt to understand the link between epigenetic modifications (DNA methylation and microRNAs) and COVID-19 severity in the presence or absence of severe acute respiratory syndrome and pneumonia, in Turkish patients [4]. This evidence concerns the gene TMPRSS2 and COVID-19.