Fine-mapping of a candidate region associated with milk-fat composition on Bos Taurus Autosome 17

A genomic region associated with milk-fat composition has been detected on BTA17. However, no candidate gene or causal variant has been identified so far. Our goal was to fine-map this region by using imputed 777k SNP genotypes. Phenotypes and genotypes were available on 1,581 animals. Phenotypes consisted of gas chromatography measurements of C8:0, and genotypes consisted of the imputed 777k SNP. Single SNP analyses were run using an animal model to retrieve significant SNP. Based on these SNP, haplotypes were constructed. Haplotypes suggested the presence of one QTL within the fine-mapped region. This QTL explained 9% of the genetic variation in C8:0. Although many genes are present in this QTL region, most of these genes have not been characterized yet. Therefore, no clear candidate gene associated with milk-fat composition could be identified.