Study of metabolic pathways of genes associated with fatty acid profile of Nellore cattle meat

• Grant number: 15/08798-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: January 06, 2016
• End date: May 05, 2016
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Principal Investigator: Fernando Sebastián Baldi Rey
• Grantee: Marcos Vinícius Antunes de Lemos
• Supervisor: Susan Kay Duckett
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Institution abroad: Clemson University, United States
• Associated to the scholarship: 13/11853-4 - Analysis of copy number variations in the genome of Nellore and its associations with the fatty acid profile of the meat, BP.DR

Abstract

Fatty acids from beef may contribute a preliminary form to human health and have received considerable attention in recent years. Several studies using taurine breeds showed the existence of genetic variability and thus the possibility of genetic improvement of fatty acid composition in beef cattle. This study will identify regions associated with beef fatty acid profile, in Longissimus thoracis muscle, from confined Nellore, using single-step (ssGWAS) method and describe the metabolic pathways of genes associated with fatty acids synthesis. The following fatty acids (FA) will be analysed by ssGWAS: lauric (C12:0), palmitic (C16:0), stearic (C18:0), oleic (C18:1 cis-9), linoleic (C18:2 cis-6), CLA (C18:2 cis-9 trans-11), CLA (C18:2 cis10 trans12), linolenic (C18:3 n3), myristic (C14:0), myristoleic (C14:1), docosahexaenoic (C22:6 n3), elaidic (C18:1 n9t), vaccenic (C18:1 t11), eicosatrienoic (C20:3 n6 cis-8,11,14), alfa-linolenic (C18:3 n6). The proportion of saturated, monounsaturated, polyunsaturated, n-6 and n-3 FAs will be calculated using the individual FA concentration. The relationship between polyunsaturated fatty acids / saturated fatty acids and n-6 / n-3 will also calculate. For genotyping of 1,616 animals, a panel of SNP 777.962 BovineSNP BeadChip (High-Density Bovine BeadChip) was used. The quality control of database will be: monomorphic markers and MAF (frequency minor alleles) of less than 0.05; markers that showed rate assignment of genotypes (call rate) lower than 90%; markers with excess of heterozygous genotypes and those with average intensity of the low cluster. The model for the (co)variance and genetic parameter estimation include the random genetic additive direct effect, the fixed effect of the contemporary groups, and the animal's slaughter age as a covariable. To perform the genome-wide association analyses, the ssGWAS method will applied, which is a modification of BLUP with numerator relationship matrix A-1 matrix replaced by H-1. The variances components and genetic parameters will estimated using the Bayesian inference, considering a linear animal model, and the GIBBS2F90 and ssGWAS computer programs will use to determine the areas of QTL, segments that will e1% of the additive genetic variance will be chosen. For identification and positioning of these segments, the database available in the "National Center for Biotechnology Information" and Ensembl Genome Browser will be used and for describe the metabolics pathways of the genes associated with the traits, the DAVID platform will be used. (AU)