Polymorphism identification in goat DGAT2 gene and association analysis with milk yield and fat percentage

In this study, we reported the analysis of DGAT2 gene polymorphisms in 468 goats of two breeds: Xinong Saanen (SN) and Guanzhong (GZ). We identified three new allelic variants: P2 (C234A), P4 (C182T) and P5 (G301T) in SN and GZ breeds. Furthermore, P2 locus was a missense mutation (Leu > Met) in both breeds. Three genotypes were found at P2 (CC, CD and DD) and P4 (AA, AB and BB) loci in SN and GZ breeds, respectively. At P5 locus, EE and EF genotypes were found in both breeds. The SNP loci were in Hardy-Weinberg disequilibrium at P2 and P5 loci in SN and GZ breeds (P < 0.01). The P4 locus was in Hardy-Weinberg equilibrium in both breeds (P > 0.05). Association of polymorphisms with milk yield and fat percentage was done in both breeds, which showed that genotypes CC, CD (P2 locus) and EE (P5 locus) had higher milk yield and fat percentage. Some of those with better performance could be used for the breeding of improved genotypes of goat. Therefore, these results suggest that DGAT2 gene is a strong candidate gene that affects milk yield and fat percentage in goat.