title: Polymorphism and gene organization of water buffalo MHC-DQB genes show homology to the BoLA DQB region.
abstract: In cattle (Bos taurus), there is evidence of more than 50 alleles of BoLA-DQB (bovine lymphocyte antigen DQB) that are distributed across at least five DQB loci, making this region one of the most complex in the BoLA gene family. In this study, DQB alleles were analysed for the water buffalo (Bubalus bubalis), another economically important bovine species. Twelve alleles for Bubu-DQB (Bubalis bubalis DQB) were determined by nucleotide sequence analysis. A phylogenetic analysis revealed numerous trans-species polymorphisms, with alleles from water buffalo assigned to at least three different loci (BoLA-DQB1, BoLA-DQB3 and BoLA-DQB4) that are also found in cattle. These presumptive loci were analysed for patterns of synonymous (d(S)) and non-synonymous (d(N)) substitution. Like BoLA-DQB1, Bubu-DQB1 was observed to be under strong positive selection for polymorphism. We conclude that water buffalo and cattle share the current arrangement of their DQB region because of their common ancestry.
authors.affiliation: Former Capes Student, Brasília, Brazil. lsena@ufpa.br
authors.forename: L
authors.initials: L
authors.lastname: Sena
authors.forename: M P C
authors.initials: MP
authors.lastname: Schneider
authors.forename: B B
authors.initials: BB
authors.lastname: Brenig
authors.forename: R L
authors.initials: RL
authors.lastname: Honeycutt
authors.forename: D A
authors.initials: DA
authors.lastname: Honeycutt
authors.forename: J E
authors.initials: JE
authors.lastname: Womack
authors.forename: L C
authors.initials: LC
authors.lastname: Skow
mesh_terms: D000818:Animals; D001483:Base Sequence; D002020:Buffaloes / Q000235:genetics*; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D040461:Gene Components; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D010802:Phylogeny; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: C507068:BoLA-DQB antigen; D017931:DNA Primers; D000949:Histocompatibility Antigens Class II