Effects of Single and Combined Genotypes of MyoG and c-fos Genes on Muscle Fiber Traits in Pig

The aim of this study was to analyze the effects of single and combined genotypes of MyoG and c-fos genes on muscle fiber traits in pig.Large White(180) and Beijing Black pigs(170)were used as experimental animals.The frozen section,H-E and SDH staining technology were used to detect the partial meat quality and muscle fiber traits.PCR-SSCP was used to detect the SNPs of MyoG and c-fos genes,the genotype frequency of SNPs were calculated,and the association of SNPs with partial meat quality and muscle fiber traits were analyzed.The results showed that:(1) A polymorphism site was detected in exon1 of MyoG gene,and three kinds of genotypes(AA,AB,BB) were detected;Two polymorphism sites were detected in exon4 of c-fos gene,and three kinds of genotypes(AA,AB,BB) were detected,respectively;(2) In the two pig breeds,the muscle fiber area and diameter decreased,and muscle fiber density increased with the increase of the allele A frequency at A2512G site.The muscle fiber density and percentage of red muscle fiber enhanced with the increase of the allele B frequency at G2650A site.And the allele A and B had significant effects on muscle fiber area and density at A2910G site;(3) The phenotype values of different traits(except for backfat thickness) had significant difference between individuals with favorable and unfavorable combined genotypes in Beijing Black pigs(P0.05 or P0.01),the phenotype values of different traits(except for backfat thickness and percentage of middle muscle fiber) had significant difference between individuals with favorable and unfavorable combined genotypes in Large White pigs(P0.05 or P0.01).The results indicate that the single nucleotide polymorphisms and combined genotypes of MyoG and c-fos genes have effect on the muscle fiber traits in pig,they could be considered as the candidate genes for muscle fiber traits.