Genome-Wide Association Study Identifies Protective Genetic Factors in Active Blood Donors Against Multiple Diseases

The healthy donor effect (HDE) refers to the observed lower mortality rate among blood donors compared to the general population. While HDE arises due to healthier individuals being more likely to be able to donate, the extent to which it is influenced by genetic differences remains largely unclear. To elucidate the genetic basis of HDE, we conducted a genome-wide association study (GWAS) involving 53,688 active blood donors with extensive donation histories and 228,060 controls from biobank cohorts within the FinnGen project. Our results identified 2,973 genome-wide significant loci associated with several health-related endpoints and levels of proteins and laboratory values. The associated loci related not only to blood groups but also to predisposition to infections and somatic and mental diseases, suggesting that HDE genetics extends beyond blood donation eligibility criteria. In conclusion, in this study we show that HDE is partially explained by genetic factors affecting various disease categories.