identification of novel snp in promoter of insulin-like growth factor-i (igf1) gene in japanese quail by pcr-sscp assay

insulin-like growth factor-1 gene (igf1) is a biological candidate gene for investigation traits such as growth, body weight and muscles growth in different species. in this research eight pairs of white and wild quails were crossed reciprocally as a base population. a total of 34 quails were produced in first generation (f1) and 422 quails were generated by intercrossing the f1 population. body weights at the time of hatching and different weeks were recorded in the second generation. the association between igf1 promoter region polymorphism and body weight in different ages was investigated in f2 generation. using pcr-sscp assay and sequencing, a novel single nucleotide polymorphism (snp) was identified in igf1 promoter region in 472 birds from three generations. genotypic frequencies of aa, ag and gg genotypes were 0.05, 0.62 and 0.33, respectively for all generations. the frequency of a and g alleles were 0.36 and 0.64, respectively. the aa genotype was lower than ag and gg genotypes for body weights in ages of one to five weeks and slaughter time and the average of daily gain was also lower from week first to four but these differences weren’t significant. the average of daily gain was higher in females compared to males for ag genotype (p