title: Maintenance of DQB1 polymorphisms in primates.
abstract: To understand the evolution of the class II major histocompatibility complex (MHC) DQB1 locus in primates, the second exons of seven DQB1 alleles from five non-human primate species were amplified by polymerase chain reaction. Comparisons of these and other primate sequences show that no between-species diversity is greater than within-species diversity, suggesting maintenance of DQB1 alleles through the history of Old-World primates. There is a preponderance of nonsynonymous nucleotide substitutions at antigen-binding-site codons; this pattern is in marked contrast to what is seen at the closely related, presumably nonfunctional DQB2 gene. The results support the hypothesis that DQB1 polymorphism is maintained by overdominant selection relating to antigen presentation.
authors.affiliation: Department of Microbiology and Immunology, Bowman Gray School of Medicine.
authors.forename: L K
authors.initials: LK
authors.lastname: Gaur
authors.forename: A L
authors.initials: AL
authors.lastname: Hughes
authors.forename: E R
authors.initials: ER
authors.lastname: Heise
authors.forename: J
authors.initials: J
authors.lastname: Gutknecht
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA; D005802:Genes, MHC Class II; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011323:Primates / Q000235:genetics*; D012044:Regression Analysis; D012689:Sequence Homology, Nucleic Acid
chemical_list: D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D004247:DNA