title: Bovine CLEC7A genetic variants and their association with seropositivity in Johne's disease ELISA.
abstract: Mycobacterium avium ssp. paratuberculosis (MAP) infection in cattle causes significant economic losses to the dairy and beef industries resulting from reduced productivity, premature culling and mortality. Bovine Dectin-1, an important pattern recognition molecule that is able to generate a proinflammatory response by acting alongside Toll like receptor (TLR) signaling, is known to co-operate with TLR2 to specifically activate a macrophage proinflammatory response against mycobacterial infections. Therefore, the goal of this study was to identify single nucleotide polymorphisms (SNPs) in the gene encoding bovine Dectin-1 (CLEC7A) and to assess their association with susceptibility to MAP infection in dairy cattle. Blood and milk samples, collected from commercial dairy operations, were tested for MAP infection using blood and milk ELISAs and a resource population consisting of 197 infected and 242 healthy cattle was constructed. Pooled DNA was used for sequencing and eight single nucleotide polymorphisms (SNPs) were identified. Identified SNPs were genotyped on the resource population using the iPLEX MassARRAY system and statistical analysis was performed using logistic regression fitting the additive and dominance effects of each SNP in the model. Out of a total of eight identified SNPs, five were successfully genotyped, and three out of these five SNPs were found to be in complete linkage. Statistical analysis revealed a strong association between a non-synonymous SNP c.589A>G (p=0.008), and MAP infection status of the resource population inferred by seropositivity in MAP antibody specific ELISAs. This SNP c.589A>G was located in the geneic region that encodes the carbohydrate recognition domain of bovine Dectin-1. Therefore, further investigation of its functional relevance is warranted.
authors.affiliation: Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: S D
authors.initials: SD
authors.lastname: Pant
authors.affiliation: Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: C P
authors.initials: CP
authors.lastname: Verschoor
authors.affiliation: Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: F S
authors.initials: FS
authors.lastname: Schenkel
authors.affiliation: Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: Q
authors.initials: Q
authors.lastname: You
authors.affiliation: Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
authors.forename: D F
authors.initials: DF
authors.lastname: Kelton
authors.affiliation: Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario N1G 2W1, Canada. Electronic address: nkarrow@uoguelph.ca.
authors.forename: N A
authors.initials: NA
authors.lastname: Karrow
mesh_terms: D000818:Animals; D001769:Blood / Q000382:microbiology; D050260:Carbohydrate Metabolism; D002417:Cattle; D002418:Cattle Diseases / Q000235:genetics* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005091:Exons; D005260:Female; D020022:Genetic Predisposition to Disease; D037181:Lectins, C-Type / Q000235:genetics* / Q000378:metabolism; D016015:Logistic Models; D008892:Milk / Q000382:microbiology; D010283:Paratuberculosis / Q000235:genetics* / Q000276:immunology; D020641:Polymorphism, Single Nucleotide; D017434:Protein Structure, Tertiary; D000099181:Dectin-1
chemical_list: D037181:Lectins, C-Type; D000099181:Dectin-1
keywords: AIC; Akaike's information criterion; BTA; Bos taurus autosome; C-type lectin; C-type lectin domain family 7 member A/Dectin-1; CD; CLEC7A; CTL; Crohn's disease; D; Dairy cattle; Dectin-1; ELISA; Enzyme linked immuno sorbent assay; IFNG; IL12; ITAM; Immune receptor tyrosine-based activation motif; Interferon-γ; Interleukin-12; JD; Johne's disease; Linkage disequilibrium; MAP; Mycobacterium avium ssp. paratuberculosis; NC; Negative control; OD; OR; Odds ratio; Optical density; PC; PCR; PRM; Pattern recognition molecule; Polymerase chain reaction; Positive control; QTL; Quantitative trait loci; S; SNP; SP110; SP110 nuclear body protein; Sample; Single nucleotide polymorphism; T-helper 1; TLR; Th1; Toll like receptor