Submitted to: Veterinary Immunology International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2004
Publication Date: 7/25/2004
Citation: Davies, C.J., Bhushan, B., Traul, D., Eldridge, J.A., Park, J.Y., Crawford, T.B., Li, H. 2004. Sequence based characterization of mhc class iia haplotypes of american bison [abstract]. Veterinary Immunology International Symposium. p. 169. Interpretive Summary:
Technical Abstract: In order to test the hypothesis that polymorphism of major histocompatibility complex (MHC) class IIa genes in American bison influences resistance to malignant catarrhal fever, we initiated the study to characterize the MHC class IIa haplotypes of 14 bison by PCR based cloning and cycle sequencing. For each animal 16 DRB3, 24 DQA and 24 DQB clones were sequenced. Preliminary, DRB3 PCR-RFLP typing results suggested that three the bison selected for sequencing were homozygotes and 11 were heterozygotes. This was confirmed by the sequencing results. However, Bibi-DRB3 sequencing identified fewer alleles than were predicted on the basis of PCR-RFLP typing. Five previously reported and six new Bibi-DRB3 alleles were present in the 14 bison. At the time of this study, there were no Bibi-DQA alleles in GenBank. Consequently, the 11 DQA alleles identified were all new alleles. The Bibi-DQA loci appear to be orthologs of the bovine (BoLA) DQA loci. Thus the Bibi-DQA alleles corresponded to the previously described BoLA-DQA subgroups. Seven of the DQA alleles were of the DQA1 subtype and five were of the DQA2 subtype. The 14 bison had 12 MHC class IIa haplotypes: eight with a single DQA gene of the DQA1 subtype; two with duplicated DQA genes, one of the DQA1 subtype and the other of the DQA2 subtype; one haplotype with two DQA2 subtype genes; and one haplotype for which we are still trying to determine the number of DQA genes. Analysis of the DQB sequences is currently in progress. Haplotypes with the three DQA subtype configurations found in the bison have previously been identified in cattle. Consequently, it appears that bison and bovine class IIa haplotypes are very closely related.