Isolation, Mapping And Snp Detection Of Two Procine Genes Related With Fat Trait And Their Association With Economic Traits

The establishment of Molecular Biology and its application in pig genetics and breeding make a breakthrough in the animal traditional breeding.In order to provide a basis for the future molecular breeding approach to improve important economic traits of the pig,many groups are struggling to establish high-density gene map(genetic and physical map) and get a full knowledge of the gene structure,function and their association with the economic traits.Recently increasing EST data and the advent of the Bioinformatics bring the investigators new ideas about the study of the genes.Based on the EST data and comparative genomics,the present study in this thesis was to isolate, characterize and physically map the novel genes.The main results are listed as follows:1.The pig specific primers were selected from the pig EST contig constructed according to the corresponding human cDNA.The fragments of five genes were successfully cloned through the PCR amplification from Yorkshire pig genomic DNA by using the primes mentioned above.2.The INRA-University of Minnesota porcine radiation hybrid(IMpRH) panel was employed to determine the precise location of the CTNNBL1 and DGAT2 genes. Results revealed that gene ctnnbl1 was located to the SSC17q21-23 and closeld to SW1920 with the LOD score threshold of 5.23.The DGAT2 gene was located to the SSC17q21-23 and closeld to SWR1445 with the LOD score threshold of 5.093.Semi-quantitative PT-PCR was used to detect gene's expression level.Results show that CTNNBL1 gene was expressed in detected tissues and high in heart and spleen.DGAT2 gene was also extensive expression in adult but highly expressed in liver.4.The mutation sites of CTNNBL1 gene and DGAT2 gene were genotyped in the experimental pig populations constructed under the cooperation of our lab and animal husbandry bureau of Tongcheng county,including Landrace,Large White,Tongcheng, Landrace♂×(Large White×Tongcheng)♀and Large White♂×(Landrace×Tongcheng)♀.The preliminary association analysis of the mutation of CTNNBL1 gene with backfat at the shoulder and backfat at the rump(p＜0.05).The preliminary results indicated that the BCNⅠ—RFLP of DGAT2 gene was highly significant correlation with backfat thickness between 6th and 7th ribs.The mutation in 3'-UTR of DGAT2 gene is highly significant correlation with backfat at the loin.5.A single nucleotide polymorphisms was found within exon 8 of CTNNBL1,which just created a enzyme recognition site for Bsu15Ⅰ.The Bsu15Ⅰ—RFLP of CTNNBL1 polymorphism was demonstrated by PCR-RFLP.The allele frequencies were determined by genotyping the different populations.