According to these criteria, we found four procoagulants (ADAMTS13, F11, HGFAC, KLKB1) and two anticoagulants (C1QTNF1, SERPINA5), whose expression may predispose males and older individuals to COVID-19-related coagulopathy and severe COVID-19 disease (Table 1, Figure 1, Table S3). This evidence concerns the gene KLKB1 and COVID-19.