Effect Of Genetic Variations Of CEBPA And AMPD1 Genes On Body Measurement And Carcass Traits Of Qinchuan Cattle

The gene pooling and sequencing,PCR-SSCP, PCR-RFLP, CRS-PCR-RFLP and DNA sequence analysis techniques were applied to scan and identification the genetic variations of candidate gene and their association with body measurement and carcass traits in 215 cattles.As a result,7 SNPs was found on the bovine CEBPA and AMPD1 genes.A new SNP was detected at CEBPA gene.6 SNPs was detected at AMPD1 gene.The association between genetic variations and body measurement and carcass traits were analyzed by using general linear model,as well as population genetic structure and distribution of genotype and allele were calculated by POPGENE software.These research will benefit for find effective molecular markers associated to body measurement and carcass traits,and give scientific theoretical basis to the improvement of Qinchuan cattle performance.The research results were displayed as follows:1. SNP detection of CEBPA gene and their assosiation between body measurement and carcass traits in Qinchuan cattleCCAAT enhancer binding protein A (CEBPA) gene was studied as a candidate gene for the body measurement and carcass traits of bovine. A new SNP g.963T>G was detected by sequencing at CDS region. Different genotypes were determined in Qinchuan cattle by restriction fragment length polymorphism (RFLP).CEBPA-Sma I Locus PCR products digested with Sma I demonstrated polymorphisms in analyzed population.We found two allelic and three genotypes in Qinchuan population.The value of polymorphism information content indicated that this was a moderate polymorphism in Qinchuan cattle. Theχ2 test indicated that the polymorphic locus in Qinchuan cattle did fit Hardy-Weinberg equilibrium (P>0.05). g.963T>G polymorphism significantly associated with carcass weight (P<0.05),genotype BB was a predominant genotype and B was a predominant allele. It is suggest that g.963T>G locus may be one of the marker-assisted selection used as carcass traits in Qinchuan cattle.2. SNPs detection of AMPD1 gene and their assosiation between body measurement and carcass traits in Qinchuan cattleThe AMPD1 was researched in the experiment. 6 SNPs were found.There were 5 SNPs and 1 deletional mutation in AMPD1 gene,namely,g.10792 A>C,g.14842 A>C,Del. g. 16214-16231 TTCCCCTCATACCACGCC, g. 19416T>C and g.19421A>G, g.22120 C>G.AMPD1-Pst I and AMPD1-Xho I Loci A SNP A10792C was detected by sequencing at CDS region. A14842C mutation was detected in intron 7 of AMPD1. Different genotypes were determined in Qinchuan cattle by Creat Restriction enzyme Site PCR (CRS-PCR-RFLP). The PCR products of AMPD1 gene exhibited two genotypes and two alleles.Theχ2 test showed that the genotype distributions in Qinchuan cattle breed was in agreement with Hardy-Weinberg equilibrium (P>0.05). The value of polymorphism information content was less than 0.25,which indicated that this was a low polymorphism in Qinchuan cattle. The association of the A10792C and A14842C mutations of AMPD1 with body measurement and carcass traits of Qinchuan cattle were analyzed,the result revealed that there were no obvious differeces (P>0.05).AMPD1-18 bp deletion Locus The objectives of the present study were focused on detecting deletion mutation in bovine AMPD1 gene, and analyzing its effect on body measurement and carcass traits in Qinchuan cattle by using DNA sequencing and agarose electrophoresis methods. Deletion g.16214-16231 TTCCCCTCATACCACGCC mutation was detected in intron 8 of AMPD1, and was located in 16214bp~16231bp. The 198 bp PCR products of AMPD1 gene exhibited three genotypes and two alleles were revealed: A and B. The frequencies of genotype AA,AB and BB in Qinchuan populations was 0.7163, 0.2233 and 0.0605. Theχ2-test analysis demonstrated that the breed was not in agreement with Hardy-Weinberg equilibrium (P<0.05). The association of the 18 bp deletion mutation of AMPD1 gene with body measurement and carcass traits of Qinchuan cattle were analyzed. The cattle with AA genotype had slaughter weight and carcass weight than those with genotype AB (P<0.01 or P<0.05). These results suggest that the 18 bp deletion mutation may influence the carcass traits in Qinchuan cattle.AMPD1-L11 Locus The linkage site g. 19416T>C and g.19421A>G mutation were detected in intron 11 of AMPD1.The polymorphism of the AMPD1 gene was detected by PCR-SSCP and DNA sequencing methods in 215 individuals from Qinchuan beef cattle breeds. The results showed that four kinds of haplotypes, named: A (T-A), B (T-G), C (C-A) and D (C-G); and the five genotypes were conflated and described as: AA (T-A/T-A), BC (T-G/C-A), AC (T-A/C-A), CC (C-A/C-A) and CD (C-A/C-G). Association of the five genotypes with body measurement and carcass traits in Qinchuan cattle breed.The animals with genotype BC had greater body length compared with genotypes AA (P<0.05) and CD (P<0.05) were observed.The genotypes BC had greater slaughter weight compared with genotypes CD (P<0.05);Individuals with genotype BC was significantly associated with carcass weight (P<0.05),and the genotype BC cattle had greater carcass weight than genotypes AA (P<0.05), CC (P<0.05) and CD (P<0.05), the BC genotype had greater dressing percentage than genotype AA (P<0.05). Other growth and carcass traits in the records had no significant association with genotypes studied. Therefore, the presence of two novel mutations in AMPD1 gene might candidate gene that affects body measurement and carcass traits in Qinchuan cattle.AMPD1-I15 locus The C22120G transversion was detected at intron 15 region.PCR-SSCP was applied to analyze the association of variations of AMPD1 gene with body measurement and carcass traits in Qinchuan cattle.The results showed that 307 bp PCR products were demonstrated three genotypes polymorphism in Qinchuan cattle population,namely,CC,CG and GG,which was not in agreement with Hardy-Weinberg equilibrium (P<0.05). The value of PIC indicated that this was a middle polymorphism in Qinchuan cattle. Correlation analysis revealed that the Individuals with genotype GG had greater body length compared with genotypes CC (P<0.05).The genotypes GG had greater carcass weight and dressing percentage compared with genotypes CC (P<0.01).