Single Nucleotide Polymorphisms of Immunity-Related Genes and Their Effects on Immunophenotypes in Different Pig Breeds

Abstract

Enhancing resistance and tolerance to pathogens remains an important selection objective in the production of livestock animals. Single nucleotide polymorphisms (SNPs) vary gene expression at the transcriptional level, influencing an individual’s immune regulation and susceptibility to diseases. In this study, we investigated the distribution of SNP sites in immune-related genes and their correlations with cell surface markers of immune cells within purebred (Taiwan black, Duroc, Landrace and Yorkshire) and crossbred (Landrace-Yorkshire) pigs. Thirty-nine SNPs of immune-related genes, including 11 cytokines, 5 chemokines and 23 Toll-like receptors (TLRs) (interferon-α and γ (IFN-α, γ), tumor necrosis factor-α (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF), Monocyte chemoattractant protein-1 (MCP-1) and TLR3, TLR4, TLR7, TLR8, and TLR9) were selected, and the percentages of positive cells with five cell surface markers of CD4, CD8, CD80/86, MHCI, and MHCII were analyzed. There were 28 SNPs that were significantly different among breeds, particularly between Landrace and Taiwan black. For instance, the frequency of SNP1 IFN-α -235A/G in Taiwan black and Landrace was 11.11% and 96.15%, respectively. In addition, 18 SNPs significantly correlated with the expression of cell surface markers, including CD4, CD8, CD80/86, and MHCII. The percentage of CD4+ (39.27%) in SNP33 TLR-8 543C/C was significantly higher than those in A/C (24.34%), at p < 0.05. Together, our findings show that Taiwan black pigs had a unique genotype distribution, whereas Landrace and Yorkshire had a more similar genotype distribution. Thus, an understanding of the genetic uniqueness of each breed could help to identify functionally important SNPs in immunoregulation.

New Insights in the Interplay Between African Swine Fever Virus and Innate Immunity and Its Impact on Viral Pathogenicity

“…Future studies are therefore required to formally demonstrate the involvement of RNA sensors in ASFV sensing and to characterize at which stage of the ASFV replication cycle this detection takes place. Interestingly, multiple single nucleotide polymorphisms (SNPs) in TLRs have been observed in wild boars ( Bergman et al, 2010 ) and in some specific breeds of domestic pigs ( Palermo et al, 2009 ; Chen et al, 2021 ), and hence it would therefore be interesting to assess their effect on ASFV innate immune sensing.…”

Leveraging an existing whole‐genome resequencing population data set to characterize toll‐like receptor gene diversity in a threatened bird

“…TLRs recognize conserved patterns of pathogens by binding residues, known as antigens, from pathogens that enter the body (Singh et al, 2003). Pathogen recognition by TLRs is necessary for the proper activation and direction of the adaptive immune response (Chen et al, 2021; Clark & Kupper, 2005; Kawasaki & Kawai, 2014; Pasare & Medzhitov, 2005; Xia et al, 2021). Studies have found that TLR gene diversity tends to be low in small, highly threatened populations compared to large populations of species of least concern (Alcaide & Edwards, 2011; Dalton et al, 2016; Knafler et al, 2017; Morrison et al, 2020).…”