Mutations in Caprine DGAT1 and STAT5A Genes were Associated with Milk Production Traits

In this study, polymorphisms of the DGAT1 and STAT5A genes were detected in 528 individuals from Xinong Saanen and Guanzhong goat breeds by PCR-RFLP, PCR-SSCP and DNA sequencing methods. Three allelic variants were identified: DQ380250: g.407_408insC, AJ237937: g.6798C>T and g.6852C>T in both breeds. At g.407_408insC locus, the frequencies of C1 allele were 0.79–0.85, and frequencies of C2 allele were 0.21–0.15. At g.6852C>T locus, frequencies of C3 allele were 0.70–0.72, and frequencies of T3 allele were 0.30–0.28. Compared with goats with C1C1 and C3C3, those with C1C2 and C3T3 genotypes had significant effects on milk yield and fat percentage (P<0.05), respectively. The result showed that does with C1C1C3T3 and C1C2C3T3 had higher milk yield than those with C1C2C3C3 (P < 0.05). In addition, the combined effect of C1C2C3T3 on milk fat percentage was the highest in comparison with other combination genotypes (P<0.05).