Association Of Polymorphism Of ESR、FSHβ、RBP4、LEF-1 And PPARD Genes With The Economically Important Traits In Large White Pigs

Marker-assisted selection (MAS) has significant advantages in the early selection, selection accuracy, compared with traditional breeding techniques. Combined with conventional breeding technique and MAS promoted the genetic advance of pig economically important traits. Therefore, studying the genetic effects of the SNPs in different pig populations could provide the important theoretical basis for the application of molecular markers in pig breeding. In the study, the effects of ESR, FSHβ, RBP4, LEF-1 and PPARD gene were detected in 633 American Large White pigs and 963 France Large White pigs by PCR-RFLP, respectively. The results were shown as following:(1) Genotypes AA, AB and BB of ESR、FSHβ and RBP4 gene were found in American and France Large White pigs, respectively. In the two pig populations, individuals with genotype BB of ESR gene had significantly higher total number born, healthy litter and birth weight than genotype AA and AB (p<0.05) in first parity and multi parity. Pigs with FSHβ and RBP4 gene genotype BB had significantly higher total number born, healthy litter and birth weight than genotype AA (p<0.05) in first parity and multi parity. In addition, genotype AA, AG and GG of LEF-1 gene were detected in American Large White pigs, but there was no significant association of the polymorphism of LEF-1 gene with teat number.(2) Three genotypes of PPARD gene (AA, AG and GG) were found in American and France Large White pigs, respectively. Genotype AA had significantly lower backfat thickness, longer body length than that of genotype AG and GG (p<0.05). RT-PCR and western blot results were used to determine that whether the SNP g.1015A>G could affect the PPARD gene expression in vivo. The expression of PPARD gene between genotype AG and GG was significantly different at both mRNA and protein level in adipose and muscle tissue. And France Large White pigs with genotype GG had significant higher expression level than that of pigs with genotype AG.Taken together, the variation of ESR gene has significant genetic effects on number born and birth weight of Large White sow, and can be applied in the marker assisted selection of litter size. The results of FSHβ and RBP4 gene was not consistent with the other reports, so more work need to be done before they are applied in pig breeding. As PPARD gene variation has significant genetic effects on backfat thickness and body length in the Large White pigs, we can reduce the backfat and increase body length in pig breeding by improving the gene frequency of favorable alleles A.