Studies On SNPs Of DECR1 Gene And Its Relations With Partial Economic Traits In Pigs

To screen single nucleotide polymorphisms(SNPs) of DECR1(mitochondrial 2,4-dienoyl-CoA reductase 1) gene, we used 692 pigs of eight breeds which including three foreign breeds(Duroc, Yorkshire, Landrace) and five Chinese native breeds (Ningxiang, Taoyuan, Daweizi, Shaziling, Wuzhishan) as experimental material. We found that there were two SNPs in Exon2 and Exon5.And genetic structure of the two SNPs was analyzed by the methods of PCR-SSCP. In addition, the relevance of different genotypes of the two SNPs and carcass traits and meat quality traits was studied. The main results are as follows:1. The DECR1 gene CDS sequence of homo sapiens, bos taurus, mice and pigs was collected via public database. The homological analysis of these CDS sequences by DNAStar shows that the homology between homo sapiens and pigs is nearest, which reaches 89.8%.2. Based on the DECR1 gene complete sequences of homo sapiens, the primers were designed and five exons of pig DECR1 gene were amplified. The SNPs of them were screened by the methods of PCR-SSCP and two SNPs in Exon2 and Exon5 were obtained.3. Genetic structure of the polymorphic locus of Exon2 in eight breeds was analyzed. There were three genotypes(CC,CG and GG) in this locus. CG was a preponderant genotype in these eight breeds. There was no CC genotype individuals in Ningxiang group. C gene was a preferential allelic in three foreign breeds while in five Chinese native breeds that was G gene. There were abundant genetic diversity in these eight breeds.4. The relevance of different genotypes of Exon2 and carcass traits and meat quality traits was studied. The difference of flesh color index between CG genotype and CC genotype was significant(P<0.05).The difference of meat marbling score between CC genotype and CG genotype or GG genotype was extremely significant(P<0.01).The difference of fat percentage between GG genotype and CC genotype was significant(P<0.05). 5. There were three genotypes(CC,CG and GG) in the polymorphic locus of Exon5.C gene was a preferential allelic in three foreign breeds but in five Chinese native breeds that was G gene. Except Landrace, whose preponderant genotype was CC,CG was a preponderant genotype in all breeds. Eight breeds had intermediate polymorphism and there were abundant genetic diversity.6. The relevance of different genotypes of Exon2 and carcass traits and meat quality traits was studied. The difference of pH Value between CG genotype and CC genotype was significant(P<0.05).The difference of pH Value between CG genotype and CC genotype was significant(P<0.05).The difference of water loss rate between GG genotype and CC genotype was extremely significant(P<0.01),and it was just the same with CG genotype and CC genotype. But the difference of water loss rate between GG genotype and CG genotype was significant(P<0.05).The difference of eye muscle area between GG genotype and CC genotype was significant(P<0.05).The difference of bone percentage between GG genotype and CG genotype was significant(P<0.05).The results show that there was a correlation between the two SNPs of DECR1 gene and meat quality traits and carcass traits.