Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 11, 2008
Publication Date: January 10, 2009
Citation: Casas, E., Wheeler, T.L., Shackelford, S.D., Bennett, G.L., Smith, T.P.L. 2009. Association of single nucleotide polymorphisms in candidate genes residing under quantitative trait loci in beef cattle [abstract]. Plant and Animal Genome XVII Conference Proceedings. Poster No. P477. Technical Abstract: The objective was to assess the association of single nucleotide polymorphisms (SNP) developed on candidate genes residing under previously identified quantitative trait loci for marbling score and meat tenderness. Two hundred five SNP were identified on twenty candidate genes. Genes selected under quantitative trait loci associated with marbling were ACADM on BTA3; NUDT4, ORL1, and A2M on BTA5; DDEF1, SQLE, and CRH on BTA14; and NYP1R, NYP2R, NYP5R, GAB1, SLC7A, INTU, and SPRY1 on BTA17. Genes selected under quantitative trait loci for meat tenderness were PIK3CG on BTA4; SOAT, IFNG, and HOM_TES on BTA5; HMGCR and PDE8B on BTA10; and DDEF1 on BTA14. Markers were evaluated in a population (n = 556) that included crossbred animals derived from Hereford, Angus, Red Angus, Limousin, Charolais, Gelbvieh, and Simmental sires. Traits evaluated included birth, weaning, and live weight; hot carcass weight; fat thickness; marbling score; yield grade; percent of animals classified as choice; dressing percentage; estimated kidney, pelvic, and heart fat; longissimus muscle area; retail product, fat, and bone yield; and meat tenderness measured as Warner-Bratzler shear force. Markers associated with marbling score resided on ORL1, A2M, DDEF1, SQLE, and SCL7A; whereas, markers associated with meat tenderness resided on IFNG, HOM_TES, HMGCR, and PDE8B. All but two genes (NUDT4 and GAB1) had SNP associated with growth and carcass traits. Groups of SNP within each gene were in linkage disequilibrium, generating haplotypes. When evaluated in additional populations and their effects validated, these markers should be suitable to be used in improvement programs.