4th International Symposium: Milk Genomics and Human Health
By Sandra Tuijtelaars, International Dairy Federation
More than 80 international experts in nutrition, genomics, bioinformatics and milk research gathered in Napa, Calif., in November for the 4th International Symposium on Milk Genomics and Human Health. Titled “Milk: from Genes to mRNA to Proteins,” the symposium was organized by CDRF. Sessions focused on the proteomics of milk, regulation of milk protein expression, post-translation modification of milk proteins, proteomics of milk peptides and glycopeptides, and bioactives of milk proteins. In addition, the International Milk Genomics Consortium (IMGC) provided impromptu highlights from researchers around the world.
Bruce German (UC Davis) started the symposium by explaining IMGC’s goals to assemble the genetic instructions for the molecules in milk that arose through evolution, and to ultimately understand the basis for their production in milk and the nutritional advantage that they provide.
The first presentation by Jenny Graves (Australian National University) demonstrated the value of comparisons between the genomes of distantly related species (such as marsupials and monotremes). Peter Williamson (University of Sydney) described a gene discovery program to exploit recent advantages in genomics for dairy industry developments. The Bovine Genome Sequencing Consortium organized manual gene model annotations which were presented by Monique Rijnkels (Baylor College of Medicine). As part of the Bovine Genome Database Consortium, David Adelson (University of Adelaide) presented a bovine quantitative trait locus (QTL), which includes a Web-accessible database of bovine QTL and linked it to the bovine genome assembly.
During a discussion on gene diversity and expression, Margaret Neville (University of Colorado) questioned whether long chain polyunsaturated fatty acids (LC-PUFA) in mouse milk are synthesized in the mammary gland or are transported from the liver. She suggested it might be possible to genetically modify the mammary glands of dairy species to secrete higher concentrations of LC-PUFA, which would be advantageous for human diets. Anke Schennink (Wageningen University) presented results from the Dutch milk genomics initiative, which revealed that large genetic variations in milk-fat composition through selective breeding can significantly improve dairy quality.
Bo Lönnerdal (UC Davis) began the second day with a discussion on bioactive milk proteins in relation to their structural features. Sharon Donovan (University of Illinois at Urbana-Champaign) presented research that showed that coupled with improved barrier function, colostrum supplementation appears to enhance innate immunity. Helen Raybould (UC Davis) reported that an understanding of the mechanisms and pathways underlying nutrient detection in the GI tract has important implications in metabolic disease, such as insulin resistance and obesity.
Patrice Martin (L’Inra au Salon international de l’agriculture) presented results on comparative gene expression profiling experiments performed to understand the underlying mechanisms of as1-casein interacting with other caseins. Tim Reinhardt (USDA/ARS) highlighted the use of shotgun proteomics and addressed some of the challenges that result from a high abundance of several key milk fat globule membrane proteins.
Anne Donnet-Hughes (Nestle Research Center) presented recent work examining a natural bacterial inoculum in breast milk. Neil Price (USDA/ARS) showed results of metabolic “chase” experiments using probiotic oligosaccharides and human milk oligosaccharides.
During the final day, participants were guided to the content and applications on the IMGC Web Portal, which were designed to be simultaneously easy for novices to browse and get results, yet powerful enough to answer detailed and abstract questions about the biology of milk and its health-giving properties for more knowledgeable users. The portal, at www.imgconsortium.org, is also an interactive environment in which users can add to the repository of knowledge of specific genes by contributing lactation-specific annotations or reference materials.
Information about the 5th International Milk Genomics Consortium Symposium in Sydney, Australia on Oct. 14-16, 2008, can be found at www.cdrf.org.
