Milk fat is a nutritious source of energy, fat-soluble vitamins, bioactive lipids, and fatty acid beneficial for human health, while it also contains fatty acids that are claimed to have unfavorable effects on human health. The milk fat composition differs between cows, which is partly due to genetics. Although there is knowledge about enzymes involved in milk fat synthesis the actual genes causing differences in milk fat composition between cows are largely unknown.
In this thesis, 50,000 DNA markers along the whole genome of 2,000 Holstein Friesian cows were screened for associations with individual bovine milk fatty acids. This resulted in the confirmation and refinement of DNA regions involved in milk fat composition. Moreover, new regions and candidate genes were identified.
Identification of DNA regions, and preferably individual genes, responsible for genetic variation in bovine milk fat composition enhances the understanding of biological pathways involved in fatty acid synthesis, which is useful for approaches aimed at changing the fatty acid composition of dairy products.