EN
Thie study aimed at comparing polymorphisms in exons of the IGFBP-1 gene encoding insulinlike growth factor binding protein-1 among three chicken breeds and analysing the associations between its genotypes and body weight traits in the Jinghai Yellow chicken. Three mutations (A2276T, T2359C and T5550C) and one insertion/deletion (the inserted/deleted AAT after position 5692bp) were detected in three chicken breeds. The general linear model analysis showed that the Jinghai Yellow chickens with BB and AB genotypes at the position 2276 (A2276T transversion) had significantly higher body weight than those of AA genotype (P<0.05 or P<0.01) at week 4, 8, and 16 of age. Moreover, BB genotype had significantly higher body weight at week 12 of age than those of AB genotype (P<0.01). The B allele had a positive effect on body weight traits.