ABO and COVID-19: We identified a cluster of 10 aptamers (targeting SVEP1, coagulation factor VIII, ferritin, heme oxygenase 1, van Willebrand factor, plasminogen, PLOD2, and CD14) sharing a genetic signal (regional probability: 0.88; rs941137; Supplementary Fig. 5), which was in high LD (r2=0.85) with the lead ABO signal associated with a higher risk for respiratory failure among COVID-19 patients.