Epistatic interactions associated with fatty acid profile of beef from Nelore cattle

Abstract

The meat is an important source of amino acids, vitamins, minerals and fatty acids (FA). Health consciousness among consumers has grown the more information and misinformation is publicized about the effects of food components, the demand for healthier products increased, and recently the composition of fatty acid contents in beef cattle. Several studies with taurine breeds indicate the existence of genetic variability in the fatty acid profile of beef. Genomic selection has been suggested as an alternative to deal with complex traits such as fatty acid composition of meat. Epistasis is a non-additive genetic effect, and it occurs between SNPs (single nucleotide polymorphisms), genes or QTLs (quantitative trait loci). Approaches have already been made to model epistatic effects in genomic selection, however, studies that consider the identification of epistatic effects among genomic regions are still rare in livestock animals. The variation of fatty acids can be explained by the characterization and identification of epistatic interactions that may be useful for phenotype prediction for commercial animals. In this sense, the aim of this study is to identify epistatic interactions for each fatty acid trait in Nelore cattle meat. Data from 943 Nelore male animals from farms that integrate DeltaGen, CRV PAINT and Nelore Qualitas breeding programs and that also participates in the Thematic Project (FAPESP Process: 2009/16118-5) and Young Researcher Project (FAPESP Process: 2011 / 21241-0 ) will be used. The FA profile will be analyzed in Longissimus thoracis samples using gas chromatography, and capillary column of 100m. Animals were genotyped using the BovineHD BeadChip (High-Density Bovine BeadChip) Illumina® with 777,000 SNPs. The software EPISNPmpi and EPISNP will be used to analyze FA traits and to identify epistatic interactions. For the windows analyses, the BayesC model will be used in GenSel software to adjust SNPs and epistatic effects. Enrichment analysis of the genes and GO terms identification will be searched at ENSEMBL Biomart. Terms associated with metabolic processes of FA will be used to identify genes associated with epistasis of FA. The present project provides a unique opportunity for study and genomic association based on epistatic interactions for fatty acid profile in the meat of Nelore cattle. (AU)