A single nucleotide polymorphism (SNP) site, alleles
A and
C, within promoter region of
insulin-like growth factor 1 gene (
IGF1) showed significant association with chicken growth, body composition and skeletal traits. In the present study, we performed genotyping of this SNP in Asian native chicken populations, layer and broiler populations using PCR-RFLP and comparison of gene expression level and growth traits among the SNP genotypes. By the PCR-RFLP, allele
C frequency was estimated to be within the range of 0.64-1.00 in 12 Asian native chicken populations, 0.48-1.00 in eight layer stocks and 0.00-0.14 in two broiler stocks examined in this study. In all chicken populations, the observed number of each SNP genotype was in good agreement with the Hardy-Weinberg expectations. Body weight (BW), average daily gain (ADG), growth rate and
IGF1 gene expression level in three-week liver were compared among three SNP genotypes obtained by
AC×AC crossing. The rankings of each genotype with respect to BW, ADG and growth rate were
AA>AC>CC, and statistical significance (
P<0.05) was found within
AA and
CC in BW and ADG. The rankings of each genotype with respect to the
IGF1 gene expression level was
AC>AA>CC. Although we could not find statistically significant difference among the genotypes in the growth rate and the gene expression level, the mean values of
CC were lower than those of
AA in all traits.
抄録全体を表示