US-AUSTRALIAN ACADEMIES JOINT WORKSHOP

US-AUSTRALIAN ACADEMIES JOINT WORKSHOP ON VERTEBRATE COMPARATIVE GENOMICS
Beckman Conference Centre, Irvine, California, 23-25 May 2007

A genome map of divergent artificial selection between Bos taurus dairy cattle and Bos taurus
beef cattle
by Ben Hayes

Dr Hayes has ten years of research experience in genetic improvement of livestock and aquaculture species, with a focus on integration of molecular information into breeding programs, and breeding program design. More recently his interest has been on the development of bioinformatic pipelines for sequence analysis. He is author and co-author of book chapters and papers contributing to knowledge of genetic mechanisms underlying quantitative traits, linkage and linkage disequilibrium mapping and marker assisted selection in livestock and aquaculture species.

A number of cattle breeds have become highly specialised for milk or beef production, following strong artificial selection for these traits.  In this paper we compare allele frequencies from 9323 single nucleotide polymorphism (SNP) markers genotyped in dairy and beef cattle breeds averaged in sliding windows across the genome, with the aim of identifying divergently selected regions of the genome between the production types.  The value of the method for identifying selection signatures was validated by three pieces of evidence.  Firstly, differences in allele frequencies between dairy and beef cattle at individual SNPs were correlated with the effects of those SNPs on production traits.  Secondly, the largest differences in sliding window average difference in allele frequencies were found on chromosome 20 in the region of growth hormone receptor gene, which carries a mutation known to have an effect on milk production traits in a number of dairy populations.  Finally, the location of selection signatures between dairy and beef cattle was correlated with the location of selection signatures within dairy cattle, for the chromosome where this was tested. 

Contact details:
Computational Biology, Animal Genetics And Genomics
Primary Industries Research, Victoria
475 Mickelham Rd, Attwood, Victoria 3049

Tel: +61 3 9217 4200
Fax: +61 3 9217 4299
Email: ben.hayes@dpi.vic.gov.au