title: The ABO blood group is a trans-species polymorphism in primates.
abstract: The ABO histo-blood group, the critical determinant of transfusion incompatibility, was the first genetic polymorphism discovered in humans. Remarkably, ABO antigens are also polymorphic in many other primates, with the same two amino acid changes responsible for A and B specificity in all species sequenced to date. Whether this recurrence of A and B antigens is the result of an ancient polymorphism maintained across species or due to numerous, more recent instances of convergent evolution has been debated for decades, with a current consensus in support of convergent evolution. We show instead that genetic variation data in humans and gibbons as well as in Old World monkeys are inconsistent with a model of convergent evolution and support the hypothesis of an ancient, multiallelic polymorphism of which some alleles are shared by descent among species. These results demonstrate that the A and B blood groups result from a trans-species polymorphism among distantly related species and has remained under balancing selection for tens of millions of years-to date, the only such example in hominoids and Old World monkeys outside of the major histocompatibility complex.
authors.affiliation: Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA. lsegurel@uchicago.edu
authors.forename: Laure
authors.initials: L
authors.lastname: Ségurel
authors.forename: Emma E
authors.initials: EE
authors.lastname: Thompson
authors.forename: Timothée
authors.initials: T
authors.lastname: Flutre
authors.forename: Jessica
authors.initials: J
authors.lastname: Lovstad
authors.forename: Aarti
authors.initials: A
authors.lastname: Venkat
authors.forename: Susan W
authors.initials: SW
authors.lastname: Margulis
authors.forename: Jill
authors.initials: J
authors.lastname: Moyse
authors.forename: Steve
authors.initials: S
authors.lastname: Ross
authors.forename: Kathryn
authors.initials: K
authors.lastname: Gamble
authors.forename: Guy
authors.initials: G
authors.lastname: Sella
authors.forename: Carole
authors.initials: C
authors.lastname: Ober
authors.forename: Molly
authors.initials: M
authors.lastname: Przeworski
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics*; D000483:Alleles; D000818:Animals; D002520:Cercopithecidae / Q000235:genetics; D019143:Evolution, Molecular; D005091:Exons / Q000235:genetics; D005838:Genotype; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D011110:Polymorphism, Genetic; D011323:Primates / Q000235:genetics*; D013045:Species Specificity
chemical_list: D000017:ABO Blood-Group System