'Weak A' phenotypes. Relationship between red cell agglutinability and antigen site density.
D000017:ABO Blood-Group System; D000371:Agglutination; D000941:Antigens; D001666:Binding Sites, Antibody; D001789:Blood Group Antigens; D004912:Erythrocytes / Q000276:immunology*; D006386:Hemagglutination Tests; D007074:Immunoglobulin G; D007457:Iodine Radioisotopes; D010641:Phenotype
D000017:ABO Blood-Group System; D000941:Antigens; D001789:Blood Group Antigens; D007074:Immunoglobulin G; D007457:Iodine Radioisotopes