Snps Of Igfbp1, Igfbp3Genes Associated With Body Weight Gain In Cyprinus Carpio Var. Jian

Animal growth was mainly regulated by the growth axis of growth hormone (GH)/insulin-like growth factor (IGF). Insulin-like growth factor binding proteins (IGFBPs) plays a vital important role on animal growth because of their regulating IGF bioavailability. Two DNA sequences of IGFBP1, exons and their approaching introns of IGFBP3were isolated from Cyprinus Carpio var. jian using RT-PCR and PCR in this sdudy. Thirty-one and thirty-six SNPs were identified on IGFBP1and IGFBP3respectively.Seven and twenty-four SNPs were located at IGFBP1a and IGFBP1b while eighteen SNPs were located at IGFBP3a and IGFBP3b respectively. PCR-RFLP was performed to detect genotypes in seven SNPs(IGFBP1b exon3_A210G, exon3_C108T; IGFBP3a intron3_G-253T; IGFBP3b intron2_G30T, intron3_A-341G, exon4_C54T, exon4_C72G) of931individuals (♂485,♀446) of Jian Carp. Correlation analysis between genotypes and weight gain showed that A210G, G-253T, G30T, A-341G, C54T and C72G were associated with female juvenile weight gain significantly (P<0.01or P<0.05) and corresponding to these six SNP loci, individuals with AG, TT, GG, AG, CC and CG genotype grew faster than other ones. A210G, C108T, G30T were significantly related to male juvenile weight gain (P<0.05or P<0.01) and GG, CC, GG individuals grew fastest. C108T, C72G and A-341T were significantly pertinent to adult weight gain (P<0.01or P<0.05). Individuals with CC and CT at C108T were significantly larger than TT ones (P<0.01). The CG type at C72G and AG type at A-341G adult weight gains were significantly higher than other types’(P<0.05). It Showed that heterozygous loci individuals grew faster, verifying the theory of heterosis. A210G and G-253T were also significantly related to male adult weight gain, of which individuals with AG type at A210G grew significantly faster than AA ones and similar trend was found in the female population though no significance (P>0.05). The male individuals of GT type at G-253T were significantly larger than GG and TT types’. The SNP G30T was significantly associated with female adult weight gain. The weight gains of GG and GT type female fish were significantly (P<0.05) larger than TT type’s while the GG male adult individuals also grew faster than other types’though no significance. Nine diplotypes were constructed based on two SNPs in IGFBP1. By multiple comparisons, we found that the body weight gains for diplotypes D4, D5, D7were significantly larger than those of D2, D6, D9(P<0.05or P<0.05). Weight gains increased with the enrichment of molecular SNPs markers in IGFBP3, consistent with the characteristics of quantitative traits. To conclude, AG type at A210G, CC type at C108T, GG type at G30T, AG type at A-341G and CG type at C72G could be used as faster growth molecular markers in C. carpio var. jian. Real-time quantitative PCR results indicated that relative expressions of IGFBP1and IGFBP3in liver of Jian Carp were higher. In different developmental stage, the expression of IGFBP1and IGFBP3showed tissue-specific and stage-specific.