title: Allelic diversity of the MHC class II DRB genes in brown bears (Ursus arctos) and a comparison of DRB sequences within the family Ursidae.
abstract: The allelic diversity of the DRB locus in major histocompatibility complex (MHC) genes was analyzed in the brown bear (Ursus arctos) from the Hokkaido Island of Japan, Siberia, and Kodiak of Alaska. Nineteen alleles of the DRB exon 2 were identified from a total of 38 individuals of U. arctos and were highly polymorphic. Comparisons of non-synonymous and synonymous substitutions in the antigen-binding sites of deduced amino acid sequences indicated evidence for balancing selection on the bear DRB locus. The phylogenetic analysis of the DRB alleles among three genera (Ursus, Tremarctos, and Ailuropoda) in the family Ursidae revealed that DRB allelic lineages were not separated according to species. This strongly shows trans-species persistence of DRB alleles within the Ursidae.
authors.affiliation: Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Goda
authors.forename: T
authors.initials: T
authors.lastname: Mano
authors.forename: P
authors.initials: P
authors.lastname: Kosintsev
authors.forename: A
authors.initials: A
authors.lastname: Vorobiev
authors.forename: R
authors.initials: R
authors.lastname: Masuda
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D005802:Genes, MHC Class II; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D001503:Ursidae / Q000145:classification / Q000235:genetics* / Q000276:immunology*
chemical_list: D017931:DNA Primers