Cloning Of Partial Sequence Of IGF-Ⅰ Gene And Associations Of Variation With Growth And Carcass Performance In Goose

Insulin-like growth factor-Ⅰ(IGF-Ⅰ)is a kind of peptide which has extremely broad functions in animal body.IGF-Ⅰis an important gene which is mainly related to animal growth by regulating growth hormorn.By means of comparative genomics,primers were designed using Primer Premier5.0 and Dnastar programme to clone the 5' -flank region and exon 4 region of IGF-Ⅰgene in Wanxi-White geese and Landaise geese.PCR-SSCP method along with fragment sequencing was used to test gene mutation,by means of associations of variation with growth and carcass performance in goose so that we will find the genetype of major gene which regulate growth performance.The IGF-Ⅰ5' -flank region and exon 4 region of Wanxi-White geese and Landaise geese were cloned(GenBank accession number:EF382668;EF460850)by the method of Genomic comparison.Homological analysis suggested that the homology of IGF-Ⅰ5' -flank region between Wanxi-White geese and the chicken as well as pig were 94%and 79%, respectively.The homology of exon 4 region between Wanxi-White geese and the chicken was 82%.PCR-SSCP dection and fragment sequencing were used in gene mutation test at pro1 and pro2 loci.The results showed that SNPs were detected at the 5' -flank region fragment amplified by Pro1 and Pro2 prime respectively.Four SNPs:A-26 T,A-215G,A-314 G, A-325T.No polymorphic site was detected at exon 4 amplified fragment.The putative binding transcriptional proteins of 5' -flank region were predicted using TFSEARCH ver1.3 on line.The result revealed A-314 G and A-325T that led to changes of transcription factor.SNP of A-314G led to the increase of regulation factors NⅢ-2.SNP of A-325T led to the increase of regulation factors Hb,GATA-2 and GATA-1.Genetic analysis suggested that,among Wanxi-White geese populationm,two allele frequencies detected by Pro1 primer were 0.82 and 0.18 respectively,and allele frequencies detected by Pro2 were 0.74 and 0.26 respectively.χ~2 fitness test showed that the population was in the state of Hardy-Weinberg equilibrium at the two sites.In Landaise goose population, allele frequecies detected by Pro1 and Pro2 were 0.16,0.84 and 0.29,0.71 respectively.χ~2 fitness test showed that the population was in the state of Hardy-Weinberg disequilibrium at the two sites.Associations of 5'-flank region Variation with growth and carcass performance in goose showed there was a singnificant corretion among CC,CD and DD genetype on Body weight at 6 weeks of age,and body weight at 8 weeks of age,Percentage of half eviscerated yield,the weight of breast muscle(P＜0.05).There was a highly singnificant corrretion among CC,CD and DD on liver weigh in Wanxi-White geese(P＜0.01).As a rerult,the locus of DD genetype might be a molecular marker for trait.