Mass-scale red cell genotyping of blood donors

Blood centers are able to recruit and process large numbers of blood donations to meet the demand for antigen-matched blood. However, there are limitations with the use of hemagglutination that can be circumvented with blood group genotyping. Antisera do not exist for several clinically important blood group antigens and many methods have been developed (direct hemagglutination, indirect antiglobulin-dependent, solid phase, or gel column). There is increasing interest to apply mass-scale red cell genotyping of blood donors to find rare (predicted) phenotypes, rare combinations of antigens and locus haplotypes, and to have access to information on the common clinically relevant blood group antigens. This review outlines technological advances, emerging algorithms, and the future of mass-scale red cell genotyping of blood donors.