Biochemistry of rhesus (Rh) blood group antigens

Although the molecular nature of several blood group antigens was established in 1950-1980, the identification and characteristics of the Rh-antigens long remained unsolved. In 1982 two groups were able to conclusively identify the RhO(D) antigen as a cell surface polypeptide with an apparent molecular weight of about 30,000. This protein has now been relatively well characterized. It seems to lack carbohydrate, it is strongly bound to the membrane skeleton, and it is posttranslationally modified by fatty acid acylation. Its NH2-terminal amino acid sequence has been determined. It is relatively hydrophobic, and its absence or decrease results in fragile erythrocytes or spherocytes. Its wide distribution in erythrocytes of various animals indicates that it plays an important physiological role.