Fine mapping of quantitative trait loci and assessment of positional candidate genes for backfat on bovine chromosome 14 in a commercial line of Bos taurus1

Abstract

Backfat thickness is one of the major quantitative traits that affect carcass quality in beef cattle. In this study, we have fine mapped a QTL for backfat EBV on bovine chromosome 14, using an identical-by-descent haplotype-sharing analysis, in a commercial line of Bos taurus. We also examined the association between gene-specific single nucleotide polymorphism (SNP) markers of the genes diacylgcerol acyltransferase 1 (DGAT1) and thyroglobulin (TG) and the backfat EBV. The results indicate that the QTL region for backfat identified on chromosome 14 is in agreement with previous studies. However, neither of the two polymorphisms of candidate genes tested, DGAT1 nor TG, showed a significant (P > 0.10) association with the backfat EBV in the cattle populations examined. However, a strong association (P = 0.0058) was detected between a microsatellite marker (CSSM66) lying approximately mid-way between the two candidate genes and the backfat EBV. These results suggest that other SNP of DGAT1, TG, or other gene(s) in the chromosomal region should be examined to test whether they have a significant effect on lipid metabolism.

Prospecting candidate SNPs for backfat in Canchim beef cattle

“…An indicative association (P ≤ 0.07) was found between DDEF1g.279401A>G SNP (Table 1) and backfat thickness. A QTL for fat thickness has been described in this chromosomal region (Moore et al, 2003). The protein encoded by DDEF1 gene was associated with differentiation of fibroblasts into adipocytes (King et al, 1999) and an SNP of this gene was associated with marbling in beef cattle (Casas et al, 2009).…”

“…Bovine chromosomes 4 (BTA4) and 14 (BTA14) harbor quantitative trait loci (QTLs) for fat traits, such as marbling score and backfat thickness (Moore et al, 2003;Mizoguchi et al, 2006). Some genes, such as leptin (Stone et al, 1996) on BTA4 and thyroglobulin on BTA14 (Barendse et al, 2001), have been indicated as candidates that can influence these traits, although some of the results are conflicting (Buchanan et al, 2002;Casas et al, 2005;Rincker et al, 2006;Gan et al, 2008;Sherman et al, 2008).…”

Effect of DGAT1 and TG gene polymorphisms on intramuscular fat and on milk production traits in different cattle breeds in Hungary

“…DGAT1 and TG gene physically maps to the centromeric region of bovine chromosome 14 (Coppieters et al, 1998;Winter et al, 2002). DGAT1 and TG genes are at least moderately linked, being separated by about 25cM (Thaller et al, 2003b;Moore et al, 2003).…”

Identification of SNPs in TG and EDG1 genes and their relationships with carcass traits in Korean cattle (Hanwoo)

“…Previous study reported that TG gene, located on BTA14, was considered as functional candidate gene for fat deposition in beef (Rincker et al, 2006). This gene have been mapped as a candidate gene which effects on lipid metabolism (Moore et al, 2003). Also, previous study indicated that the T354C SNP of TG gene was significantly associated with marbling score (Hou et al, 2011).…”