Associations Of Regulatory Region Polymorphisms In Multiple Genes With Feed Efficiency In Broilers

The expression of multiple genes influences a variety of poultry traits like body weight (BW), BW gain (BWG), feed intake (FI) and feed conversion ratio (FCR). From the perspective of regulate intestines nutrition transporters and growth factor gene expression, we screened 1000bp upstream of 10 amino acid transporters (rBAT, b0+AT,EAAT3, y+LAT1, y+LAT2, B0AT1, CAT], CAT2, SLC22A3, LAT1),1 sugar transporters (SGLT1) and 1 growth factor (FGF1) for single nucleotide polymorphism (SNPs) and identified the association of several representative SNPs with BW at 49 days (BW49) and 70 days (BW70), BWG, FI and FCR in 2 genetically unrelated yellow meat-type chicken strains (N202, N301). In this study, we found 108 SNPs upon 1000bp upstream of above genes.7 SNPs were selected by two-tailed comparison method are potentially related to FCR, which are T-834C of B0AT1, T-761G, G-713A, T-658C, G-568T of rBAT, G-490A of SGLT1, T-899C of FGFl. In order to further study, we selected 2 SNPs from candidate functional genes (B0AT1, FGF1) as the research object to verify the association between the polymorphism and FCR in whole population. T-834C, T-899C in B0AT1 and FGF1 genes were genotyped by fragment analysis. The results showed that the allele frequencies of T-834C of B0AT1 was in Hardy-Weinberg equilibrium in N301 strain and had significantly associated with FCR (P< 0.01) and the C allele has certain effect on body weight. The allele frequencies of T-899C of FGF1 were in Hardy-Weinberg equilibrium in both strains and had significantly associated with FCR (P< 0.01) in N301 strain. Furthermore, birds with TC genotype of T-834C showed strongly lower FCR (P< 0.01) compared with TT and CC individuals in N301 strain. Individuals with CC genotype of T-899C had significantly lower FCR (P< 0.05) than those with TC genotype in N301 strain. In this experiment, we studied the SNP in the upstream regulatory region of multiple genes, discussed the effect of SNP on regulating expression and analyzed the effects of some genotypes on feed efficiency traits.