Diacylglycerol acyltransferase-2 (DGAT2) plays a key role in the synthesis of animal triglycerides (TGs). This study investigated the relative expression of the DGAT2 gene in tissues, variation in the gene, and its association with carcass and meat quality traits in yaks (Bos grunniens). DGAT2 was found to be expressed in twelve tissues investigated, but the highest expression was detected in subcutaneous fat, and moderate levels were observed in the liver, heart, longissimus dorsi muscle, and abomasum. Three variants (A₁ to C₁) were found in intron 5 and another three variants (A₂ to C₂) were found in intron 6, with two single-nucleotide polymorphisms (SNPs) being identified in each region in 694 Gannan yaks. Variants B₁ and C₂ were associated with a decrease in Warner⁻Bratzler shear force (WBSF) (p = 0.0020 and p = 0.0441, respectively), and variant C₁ was associated with an increase in WBSF (p = 0.0434) and a decrease in drip loss rate (p = 0.0271), whereas variant B₂ was associated with a decrease in cooking loss rate (p = 0.0142). Haplotypes A₁-A₂ and B₁-A₂ were found to be, respectively, associated with an increase and a decrease in WBSF (p = 0.0191 and p = 0.0010, respectively). These results indicate that DGAT2 could be a useful gene marker for improving meat tenderness in yaks.
Keywords: DGAT2; carcass trait; meat quality trait; tissue expression; variation; yak.