The TG5 thyroglobulin gene test for a marbling quantitative trait loci evaluated in feedlot cattle

Abstract

The TG5 (thyroglobulin 5 ′ leader sequence) single nucleotide polymorphism has been associated with marbling in cattle fed for periods longer than 250 days. To test whether the association could be detected in diverse cattle, fed for less than 250 days, and to measure the size of the effect, we sampled 1750 cattle from the AMH Toowoomba feedlot. These cattle were sampled on 28 separate days, over 9 months. Their marbling scores covered the complete range. We found that the TG5 single nucleotide polymorphism was associated with marbling scores ( P <0.05) and estimated that TG5 genotypes explained 6.5% of the residual deviance for the marbling phenotype. We also found that the '3' allele was more frequent in animals with higher marbling scores. The consistency of the allelic association between studies and, in particular, the association found in diverse cattle, indicate that the TG5 polymorphism can be used as a breeding tool and possibly a feedlot entry tool. To estimate the size of the genetic region in which the marbling quantitative trait loci are located, we tested the nearby DNA markers CSSM66 and BMS1747. These do not show allelic associations to marbling. The consistency of the allelic association between studies, the lack of association to nearby DNA markers and the complementary information on gene action of genes near Thyroglobulin suggest that DNA sequence variations, in or near the Thyroglobulin gene sequence, are the likely causes for the marbling quantitative trait loci. Further studies of single nucleotide polymorphism in and near the Thyroglobulin DNA sequence should allow causal mutations for the effect to be identified.

A meta-analytic assessment of a Thyroglobulin marker for marbling in beef cattle

“…They reported significantly higher IMF values for TT genotypes against CC genotypes in German Holsteins. Their results suggested a recessive effect of the T allele on marbling, also found by Barendse et al [4], but were based on small studies with just three German Holsteins and one Charolais having TT genotype.…”

“…The data for Study 6 was first analysed in [4]. The excluded studies were described in [22] and [5].…”

“…Thaller et al [22] and Barendse et al [4] suggested that the T allele may have a recessive gene effect on marbling, so we re-analysed the data using this assumption. Recessivity alters the maximum genetic variance and places it at p T = 1/ √ 2.…”

Detecting quantitative trait loci affecting beef tenderness on bovine chromosome 7 near calpastatin and lysyl oxidase

“…Barendse et al 1993Barendse et al , 2004Maniatis et al 1982). DNA was diluted to about 50 ng/µL for the working stock and plated into a 96 well format.…”

Association of CAPN1 316, CAPN1 4751 and TG5 markers with bovine meat quality traits in Mexico

“…The micromolar calcium-activated neutral protease (CAPN1) is encoded by the CAPN1 gene and 3 markers (CAPN1 316, CAPN1 4751 and CAPN1 530) have been developed in this gene that are associated with meat tenderness (Page et al, 2002(Page et al, , 2004White et al, 2005;Casas et al, 2005Casas et al, , 2006. The TG5 marker (thyroglobulin 5' leader sequence) is a single-nucleotide polymorphism (SNP) that has been associated with marbling (Barendse et al, 2004;Barendse, 2005). TG5, CAPN1 316 and CAPN1 4751 markers have been included in some commercial DNA-tests (GeneSTAR and Igenity TenderGENE) engineered to predict productive traits.…”