The Co antigen is important in transfusion medicine. 99.8% of people possess the Co(a) allele. Individuals with Co(b) allele or who are missing the Colton antigen are at risk for a transfusion reaction such as hemolytic anemia or alloimmunization. Antibodies against the Colton antigen may also cause hemolytic disease of the newborn, in which a pregnant woman's body creates antibodies against the blood of her fetus, leading to destruction of the fetal blood cells.[3]
^Denker BM, Smith BL, Kuhajda FP, Agre P. Identification, purification, and partial characterization of a novel Mr 28,000 integral membrane protein from erythrocytes and renal tubules. J Biol Chem 1988;263:15634-15642. PMID3049610
^King LS, Choi M, Fernandez PC, Cartron JP, Agre P.Defective urinary-concentrating ability due to a complete deficiency of aquaporin-1. N Engl J Med. 2001 Jul 19;345(3):175-9. PMID11463012