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SNP located on three candidate genes influencing growth, performance and carcass traits in a population of steers sired by Braunvieh, Charolais and Simmental Bulls
The objective of the current study was to evaluate the association of single nucleotide polymorphisms (SNP) on three candidate genes for growth, performance, carcass traits in 39 steers sired by Braunvieh, Charolais and Simmental bulls. Single nucleotide polymorphisms from three candidate genes including the Thyroglobulin gene (TG), the Adiponectin (ADPOQ) gene and the Insulin-like growth factor 1 (IGF-1) gene were utilized for association analyses. Single nucleotide polymorphisms were selected utilizing SNP that were evenly distributed and represented the total length of the candidate gene. Of the 67 SNP genotyped, 20 were chosen for TG, 20 for ADPOQ, and 27 for IGF-1. Linkage disequilibrium (LD) was not evaluated in the current study due to the small population size however, LD will be calculated as the genotyped population becomes larger in future studies. The growth traits that were evaluated included, birth weight (BW), hip height (HH), and weaning weight (WW). Carcass quality and composition traits included marbling score (MS), back fat thickness (BF), ribeye area (REA), hot carcass weight (HCW), and yield grade (YG). The mixed model procedure of SAS was utilized to evaluate associations of the 67 SNPs and measured traits. Sire breed and SNP genotype were fit in the model as fixed effects with performance and carcass traits fit as random effects. Associations between traits and SNP’s were reported as significant if P <0.05. Multiple SNP from all three candidate genes were identified as being significantly associated (P < 0.05) all traits evaluated in the current study. Association analyses for growth traits revealed seven SNP significantly associated with BW (rs109830314, rs383724494 rs378724414, rs381911082, rs383535987, rs384076273, rs109327701), five with HH(rs110553649, rs132813094, rs210258853, rs109327701, rs137651874), ten with WW (rs109182502, rs110616947, rs377997897, rs379996188, rs380627374, rs378724414, rs109327701, rs136982429, rs137140434, rs137726884) ten with BF (rs110501231, rs110616947, rs378567477, rs382644882, rs210258853, rs137140434, rs137374423, rs137601357, rs137662301, rs137726884). Association analyses for carcass quality and composition traits revealed two SNP significantly associated with HCW (rs110501231, rs378567477) four with MS (rs378567477, rs378900777, rs383535987, rs137104571), two with REA (rs109830314, rs137651874), and 5 with YG (rs379467464, rs382252585, rs386026054, rs378724414, rs137601357). Furthermore, a total of eight SNP’s (rs109830314, rs110501231, rs110616947, rs378567477, rs378724414, rs137140434, rs137651874, and rs137726884) representing all three candidate genes were significantly associated with growth, performance and carcass quality and composition traits.
Keywords: SNP, Candidate Genes, Beef, Growth and Performance, Carcass Traits
SNP, Growth, Carcass, Candidate Genes