Genetic Polymorphisms and Genetic Effects of 5'' of MyoG Gene in Shandong Native Pig Breeds

Abstract: Single-nucleotide polymorphisms of 5' of the MyoG gene were tested using PCR-SSCP in the different pig breeds including Laiwu， Dapuliang， Yimeng Black， and Licha Black pigs， and the effects of the MyoG gene on the birth weight， the 60-day body weight， the 210-day body weight， the daily gain between 60-day and 210-day and the backfat thickness were also analyzed. On the basis of the published DNA sequence of the porcine MyoG gene (U14331)， three pairs of primers were designed， and one polymorphism was found in the PCR product amplified with 5-2 primers， and three genotypes (AA， AB， BB) exist. Amplicons were sequenced， and G→Amutation was detected at 2 080 site. Results of χ² test showed that the Laiwu and the Dapuliang pig breeds differ significantly (P<0.05) in genotype distribution from the Yimeng Black and Licha Black pig breeds. On the basis of the fixed effect model， significant differences were found in the birth weight among the different MyoG genotypes， whereas no significant differences existed in the 60-day body weight， the 210-day body weight， the daily gain between 60-day and 210-day and the backfat thickness. Using least square analysis， it was seen that individuals of the BB genotype had significantly less (P<0.01) birth weight and daily gain between 60-day and 210-day than those of the AA and AB genotypes， with the order being AA>AB>BB. These results suggest that the genotype has significant effects on the individual birth weight and the daily gain， and that the selection of the A allele is favored with regard to the birth weight and the daily gain.
    

CSTR: 32200.14.cjcb.2007.04.0034