Variations in the diacylglycerol acyltransferase-1 (DGAT1) and its association with meat tenderness in Gannan yaks (Bos grunniens)

Abstract

Diacylglycerol acyltransferase-1 (DGAT1) has been recognised as one of the functional genes during fat deposition and closely related to meat quality. It is well known that yak meat has low intramuscular fat (IMF) and poor tenderness, influencing the purchase decision for consumers. In this study, the variations of DGAT1 gene were detected using polymerase chain reaction single-stranded conformational polymorphism (PCR-SSCP) analysis so as to ascertain the association of DGAT1 variation with yak carcase and meat quality traits. Two variants (A1 and B1 ) in intron 1 – exon 2 and another three variants (A2 to C2 ) in intron 15 – exon 17 were identified in the yaks investigated. Three sequence variations (c.192-117 G > A, c.1252-23 C > T and c.1339 C > T) were detected among these variants, with c.192-117 G > A located in intron 1, c.1252-23 C > T located in intron 15 and c.1339 C > T located in exon 17. The mutation c.1339 C > T resulted in an amino acid change (p. Arg 447 Cys). Variants A1 and B2 were associated with a decrease and increase in Warner–Bratzler shear force (WBSF) (p = 0.027 and p < 0.001), respectively. Variant C2 was associated with a decrease in WBSF and hot carcase weights (HCW) (p = 0.001 and p = 0.037, respectively). The presence of haplotype H3 and absence of H5 were highly associated with a decrease in WBSF (p < 0.05). These finding suggested that the variations in DGAT1 could be potential targets for gene-assisted selection to improve meat tenderness in Gannan yak. Highlights Three SNPs were identified in the DGAT1 gene in Gannan yak. Variants (A1 , B2 and C2 ) and haplotypes (H3 and H5) have a significant influence on Warner–Bratzler shear force (WBSF) in Gannan yak. DGAT1 variations may have potential in selection for improving meat tenderness in Gannan yaks.