Abstract: A single nucleotide polymorphism (SNP，C＼T) that creates an extra GATA-1 site (T allele) in intron 4 of the swine erythropoietin receptor (EPOR) gene was genotyped use PCR-SSCP method in Large white and Landrace pigs in this study. AA, AB and BB genotypes were found in Landrace and Large white pigs populations, which showed that a moderate polymorphism. Meanwhile, the effect of polymorphism for this loci on total number born (TNB), number born alive (NBA) and born weoght (WB) were analyzed. The results indicated that the individuals of the first parity Landrace pig with BB genotype showed more WB significantly than that with AB and AA genotypes (P<0.05), the individual of multiparous sows with BB genotype showed more TNB significantly than that with AB genotype (P<0.05), and B allele might have the positive effective on TNB, NBA and WB of the first parity sow. While in Large white pig, the TNB，NBA and WB of the first parity sow with BB genotype were more than those with genotype AA and AB, but the results showed no significant difference (P>0.05). The WB of multiparous sows with AB genotype showed more WB significantly than that with AA genotype (P<0.05). B allele might have the positive effective on TNB, NBA and WB of the first parity sow.

Key words: pig; EPOR gene; polymorphism; reproductive traits; candidate gene