ABO blood groups, COVID-19 infection and mortality

Background: A recent study showed that the ABO gene, chr 9q34.2, which determines blood type, may affect COVID-19 disease severity, although this result has not been reproducible. A UK study of 2200 COVID-19 patients found no relationship of ABO blood type to disease severity. A Danish study identified ABO blood group as a risk factor for SARS-CoV-2 infection but not for hospitalization or death from COVID-19. Aim: In the current study, we wished to analyze the relationship of ABO blood group and the ABO genetic locus to COVID-19 test positivity and mortality in subjects from the UK Biobank (UKB). Methods: ABO blood type is from UKB data field 23165. Blood type was imputed for genotyped UK Biobank participants using three SNPs (rs505922, rs8176719, and rs8176746) in the ABO gene on chromosome 9q34.2. We analyzed the chromosome 9 snp rs657152 to assess the relationship of the ABO locus to COVID-19 test positivity and mortality. Results: COVID-19 test results (negative or positive) were not related to blood group in males (p = 0.977, two tailed Fisher exact test) or females (p = 0.548). COVID-19 outcomes (alive or died) were not related to blood group in males (p = 0.102, two tailed Fisher exact test) or females (p = 0.226). We found no significant relationship of rs657152 to COVID-19 test positivity or mortality. Conclusion: We were not able to confirm that ABO blood group influences risk of COVID-19 infection or outcome.