Polymorphism of G3695A of IGFBP3 Gene and Its Association with Growth Traits in Large White Pigs

The substitution G3695A within insulin-like growth factor binding protein-3 (IGFBP3) gene were identified by PCR-RFLP in 369 Large White breeding pigs, and the effects of 3 genotypes (GG, GA and AA) on 4 growth traits were analyzed. The results showed that heterozygosity (H) and polymorphic information content (PIC) of the locus G3695A were 0.448 5 and 0.396 2,respectively, and the frequencies of genotype GA and allele A were the highest. Days to 30 kg and 100 kg body weight of genotype GG were significantly shorter than those of genotype AA and GA (P 0.01), and average daily gain (ADG) of 30~100 kg of genotype GG was the highest (P 0.01). The backfat thickness at 100 kg body weight of genotype GA was significantly thinner than that of the other two genotypes (P 0.01). The mutation G3695A of IGFBP3 gene was significantly associated with growth speed and backfat thickness in Large White pigs,which could be a valuable marker in the practical pig breeding.