Expression analysis, single nucleotide polymorphisms and combined genotypes in candidate genes and their associations with growth and carcass traits in Qinchuan cattle.

The apolipoprotein E (ApoE) gene is an important component of plasma lipoprotein, and Fas apoptosis inhibitory molecule (FAIM) is a novel anti-apoptotic gene. In this study, we researched and discussed seven genes in eight different tissues in Qinchuan cattle by quantitative Real-time PCR. The result of analysis showed that ApoE and FAIM 2 genes had a correlation with muscle and fat. PCR-RFLP was applied to analyze the genetic variations of the ApoE and FAIM 2 genes and verify the effect on growth and carcass traits in a total of 365 Qinchuan cattles. The result of haplotype analysis showed that nine different haplotypes were identified among the four SNPs in ApoE and FAIM 2 genes. The statistical analyses indicated that the four SNPs were significant association with growth and carcass traits (P < 0.05, N = 365); and the four SNPs were significant association between nine combined genotypes of candidate genes and growth and carcass traits. Taken together, our results provide the evidence that polymorphisms in candidate genes are associated with growth and carcass traits in Qinchuan cattle, and may be used as a possible candidate for marker-assisted selection and management in beef cattle breeding program.