Effect of leukemia inhibitory factor polymorphism on litter size traits in Thai commercial pig breeds

Abstract

Leukemia inhibitory factor (LIF) is a crucial candidate gene that impacts on implantation process. In this study, the effects of the porcine LIF polymorphism on litter size traits were elucidated in Thai commercial pig populations. Genotyping of three single nucleotide polymorphisms (SNPs) of the porcine LIF gene was detected in coding and 3'-untranslated regions. The porcine LIF c.*24C>T was segregating in Large White, Landrace, and Large White × Landrace (LW × LR) crossbred sows. No polymorphisms at two non-synonymous SNPs loci (LIF c.28C>A and LIF c.161A>G) were found in this study. The porcine LIF c.*24C>T was significantly associated with the total number born (TNB), the number born alive (NBA), and the number of piglets weaned alive (NWA) traits in Large White and Landrace sows. Moreover, the porcine LIF c.*24C>T was associated with the NBA and NWA traits in LW × LR crossbred sows. The favorable LIF c.*24C allele was positively correlated with the litter size traits. These findings indicated that the polymorphism of the porcine LIF gene was associated with litter size traits and confirms the significance of porcine LIF as a candidate gene for litter size traits in pig breeding. Thus, the porcine LIF gene could be used for improving prolific traits in these Thai commercial pig populations.