Genomic Variant in NK-Lysin Gene Is Associated with T Lymphocyte Subpopulations in Pigs.

As an antimicrobial peptide, NK-lysin () plays an important role in the innate immune system of organisms. In this study, 300 piglets (68 Landrace pigs, 158 Large White pigs and 74 Songliao Black pigs) were used to further explore the function of gene in porcine immune system. The quantitative real-time PCR analysis detected the gene's expression, and the result demonstrated that mRNA was expressed in lung, spleen, stomach, kidney, liver and heart, and the expression level decreased sequentially. A single-nucleotide polymorphism (SNP, g.59070355 G > A) in intron 3 of the gene was detected by PCR amplification and sequencing. The results of the Chi-square (χ2) test showed that the genotype of the SNP was consistent with the Hardy-Weinberg equilibrium. What's more, association analysis results showed the SNP in gene was significantly associated with T lymphocyte subpopulations. Different genotypes had significant effects on the proportion of CD4CD8, CD4CD8, CD4CD8, CD8, CD4/CD8 in peripheral blood ( < 0.05). These results further suggested that could be recognized as a promising immune gene for swine disease resistance breeding.