Leukemia Inhibitory Factor (LIF) Gene Polymorphism and its Impact on Reproductive Traits of Pigs

The purpose of this study was to determine the frequencies of alleles and genotypes of the Leukemia Inhibitory Factor (LIF) gene (ID: 399503) in Landrace, Large White and Duroc pigs in Russia and to evaluate the impact on productive traits of pigs. Polymorphism was genotyped using PCR-RFLP method. In the course of studies we observed a different distribution of allele and genotype frequencies of different breeds. In all breeds under study all three genotypes AA, AB, BB were determined. The results of this study suggest that the LIF gene promotes the reproductive traits of pigs. The AA genotype sows compared to BB genotype analogues have better Total Number of Born (TNB) and Number Born Alive (NBA) by 1.4 and 1.3 (p<0.01) in Landrace sows, 1.3 and 0.9 (p<0.05) in Large White and 2.0 and 3.3 (p<0.001) in Duroc, respectively. The AB genotype sows exhibit intermediate values, which testifies the concentration of a favorable A allele in the pig genotype of animals contributing to the fertility. Our research revealed a positive effect of A allele and AA genotype that indicates the possibility to use this polymorphism in improving reproduction traits of sows.