Moreover, authors supported the role of ABO in COVID-19 prognosis, considering the presence of neutralizing antibodies against protein-linked N-glycans in the O-group compared to non-O blood groups [89,90] as well as the well-known link existing between the ABO-locus and coagulation von Willebrand factor gene expression (i.e., VWF; locus 12p13.31), evoking thrombosis and coagulation disturbances as one of the main mechanisms involved. Here, ABO is linked to COVID-19.