title: Sequence polymorphism in the bovine major histocompatibility complex DQB loci.
abstract: Polymorphism in DQB sequences of the bovine major histocompatibility complex was investigated in 22 British Friesian cattle. The first domain exon was amplified, cloned and sequenced. Eight different sequences were identified, six of which had not been identified previously. The high proportion of novel sequences suggests that additional polymorphisms within the DQB loci remain to be discovered in this breed. One sequence was present in at least 21 of the 22 cattle. This sequence, or a closely related sequence, has also been found in American Holstein Friesian, Swedish Red and White and Japanese Black cattle. The remarkably high sequence conservation suggests that the bovine DQB region may contain a locus with a low level of polymorphism and be more similar to the human DQB region than previously supposed. One sequence with three widely spaced frameshift insertions appeared to be a pseudogene.
authors.affiliation: Department of Veterinary Clinical Studies, University of Glasgow Veterinary School.
authors.forename: L
authors.initials: L
authors.lastname: Nasir
authors.forename: M
authors.initials: M
authors.lastname: Ndiaye
authors.forename: C
authors.initials: C
authors.lastname: Seely
authors.forename: M J
authors.initials: MJ
authors.lastname: Stear
mesh_terms: D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics* / Q000276:immunology; D005091:Exons; D016368:Frameshift Mutation; D005784:Gene Amplification; D005802:Genes, MHC Class II; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006801:Humans; D007564:Japan; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D006113:United Kingdom; D014481:United States
chemical_list: D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C057615:HLA-DQbeta antigen