Plant & Animal Genomes XVII Conference

January 10-14, 2009
Town & Country Convention Center
San Diego, CA

Milking The Bovine Genome: Insights In Role Of Milk And Variation Of Milk Composition

Monique Rijnkels^1,2,3 , Danielle G. Lemay^2,3 , Wesley C. Barris^2,3 , Theresa M. Casey^2,3 , J. Bruce German² , Angie S. Hinrichs² , Evgenia V. Kriventseva^2,3 , David J. Lynn^2,3 , William F Martin^2,3 , Nauman J. Maqbool^2,3 , Juan F. Medrano^2,3 , Adrian J. Molenaar^2,3 , Margaret C. Neville² , Katherine S. Pollard² , Gonzalo Rincon^2,3 , Evgeny M. Zdobnov^2,3 , Ross L. Tellam^2,3 , Bovine Genome Sequencing and Analysis Consortium³

¹  USDA/ARS Children’s Nutrition Research Center, Department of Pediatrics-Nutrition, Baylor College of Medicine,1100 bates st, Houston TX 77096, USA

²  http://www.imgconsortium.org/Members/niqir/lactationteam

³  http://bovinegenome.org/genomeconsortium.html

Domestic cattle are the primary providers of dairy products for human consumption. Consequently, the availability of the Bos taurus genome assembly offers the opportunity to investigate the genomic and evolutionary basis of species variation in milk composition. It also enables genome-wide studies of the genetic basis of milk production traits, and dairy-product and production properties. Genome-wide and community-based manual analyses were combined to analyze milk and lactation related genes regarding genome rearrangements and gene evolution. Genomic rearrangements have contributed to copy number variation, new variants and changes in regulation of milk protein genes, many of which have immune related functions. Compared with other genes in the genome milk and mammary related genes are more likely to be present in the mammalian genome, more conserved and evolved slower. The most divergent milk proteins are associated with nutritional and immunological functions, while the most conserved have roles in secretory processes. These findings support the essentiality of milk to the survival of mammalian neonates, and the establishment of milk secretory mechanisms more than 160 million years ago. Besides, they demonstrate that species-specific changes in genome organization and gene regulation help to tailor the functional components of milk to the specific needs of newborn mammals. Moreover, these findings add to the body of evidence supporting the important immune functions of milk proteins. Thus bovine milk is much more than simply a supply of nutrients.