Characterization of BoLa I MHC Sequence Missing from the Bovine Reference Genome

Transcripts of the bovine MHC class I gene BoLA-“BSA” (Accession no. L02832.1; AF396750.1) were previously identified as the most abundant class I mRNAs in leucocytes from an Angus bull “86”. Other very similar cDNA sequences are found in the Genebank database. However, such sequences are missing from genomic libraries prepared from Bull “86” as well as other libraries including the CHORI 240 bacterial artificial chromosome (BAC) library and the bovine reference assemblies/trace archives. We have developed a locus-specific PCR procedure to specifically amplify genomic BoLA I “BSA” and have demonstrated that the gene is present in the genomes of Bull “86” and both L1 Domino and Dominette, DNA donors for the CHORI240 BAC library and the bovine genome sequencing project, respectively. We will describe the allelic variation present at the “BSA” locus among representative BoLA haplotypes and report a trans-species polymorphism for a frameshift mutation, which has been maintained since the divergence of Bison and the auroch progenitors of domestic cattle. (Funded by USDA-NIFA grant No. 2011-68004-30367 and Foreign Animal and Zoonotic Disease Defense Center career development national needs predoctoral fellowship to EDD).