Effects of <i>INSL3</i> and <i>WNT2B</i> gene polymorphisms on seasonal reproductive traits of Xinjiang Qira black sheep, Kazakh sheep and Duolang sheep

The purpose of this study was to investigate the polymorphism and genetic correlation of <i>INSL3</i> and <i>WNT2B</i> genes with seasonal estrus and litter size in three different Xinjiang sheep breeds. The genetic diversity of <i>INSL3</i> and <i>WNT2B</i> genes were analyzed, and their association with litter size and estrous traits were analyzed. The results showed that two SNPs (SNP1, SNP2) were detected in <i>INSL3</i> gene and there were three genotypes in SNP2 (<i>INSL3</i> (A100T)), named of AA, AT and TT, A was the dominant allele. Additionally, five SNPs (SNP3, SNP4, SNP5, SNP6, SNP7) were detected in the <i>WNT2B</i> gene and there were three genotypes in SNP4 (<i>WNT2B</i> (G126T)), named GG, GT and TT, G was dominant allele. SNP2 was in Hardy-Weinberg equilibrium in three sheep breeds (<i>P</i> > 0.05). SNP4 was deviated from Hardy-Weinberg equilibrium in three sheep breeds (<i>P</i> < 0.05). Further, AT genotype of SNP2 (<i>INSL3</i> (A100T)) could significantly affect the estrus trait in Duolang sheep and Qira black sheep, and related to the litter size in Duolang sheep. The <i>WNT2B</i> significantly affected the estrus and litter size of Duolang sheep and Qira black sheep. <i>INSL3</i> (A100T) and <i>WNT2B</i> (G126T) may be potential molecular markers for controlling seasonal reproductive trait in sheep.