title: Identification of single nucleotide polymorphisms in Toll-like receptor candidate genes associated with tuberculosis infection in water buffalo (Bubalus bubalis).
abstract: BACKGROUND
  Toll-like receptors play a key role in innate immunity by recognizing pathogens and activating appropriate responses. Pathogens express several signal molecules (pathogen-associated molecular patterns, PAMPs) essential for survival and pathogenicity. Recognition of PAMPs triggers an array of anti-microbial immune responses through the induction of various inflammatory cytokines. The objective of this work was to perform a case-control study to characterize the distribution of polymorphisms in three candidate genes (toll-like receptor 2, toll-like receptor 4, toll-like receptor 9) and to test their role as potential risk factors for tuberculosis infection in water buffalo (Bubalus bubalis).
  
  
  RESULTS
  The case-control study included 184 subjects, 59 of which resulted positive to both intradermal TB test and Mycobacterium bovis isolation (cases) and 125 resulted negative to at least three consecutive intradermal TB tests. The statistical analysis indicated that two polymorphisms exhibited significant differences in allelic frequencies between cases and controls. Indeed, the TT genotype at TLR9 2340 C > T locus resulted significantly associated with susceptibility to bovine tuberculosis (P = 0.030, OR = 3.31, 95% CI = 1.05-10.40). One polymorphism resulted significantly associated with resistance to the disease, and included the CC genotype, at the TLR4 672 A > C locus (P = 0.01, OR = 0.26, 95% CI = 0.08-0.80). Haplotype reconstruction of the TLR2 gene revealed one haplotype (CTTACCAGCGGCCAGTCCC) associated with disease resistance (P = 0.04, OR = 0.51, 95% CI = 0.27-0.96), including the allelic variant associated with disease resistance.
  
  
  CONCLUSIONS
  The work describes novel mutations in bubaline TLR2, TLR4 and TLR9 genes and presents their association with M. bovis infection. These results will enhance our ability to determine the risk of developing the disease by improving the knowledge of the immune mechanisms involved in host response to mycobacterial infection, and will allow the creation of multiple layers of disease resistance in herds by selective breeding.
authors.affiliation: Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055, Portici, Italy. flora.alfano@cert.izsmportici.it.
authors.forename: Flora
authors.initials: F
authors.lastname: Alfano
authors.affiliation: Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna, 148, 10154, Torino, Italy. simone.peletto@izsto.it.
authors.forename: Simone
authors.initials: S
authors.lastname: Peletto
authors.affiliation: Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055, Portici, Italy. mariagabriella.lucibelli@cert.izsmportici.it.
authors.forename: Maria Gabriella
authors.initials: MG
authors.lastname: Lucibelli
authors.affiliation: Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055, Portici, Italy. giorgia.borriello@izsmportici.it.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Borriello
authors.affiliation: Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055, Portici, Italy. giovanna.urciuolo@tiscali.it.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Urciuolo
authors.affiliation: Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna, 148, 10154, Torino, Italy. mariagrazia.maniaci@izsto.it.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Maniaci
authors.affiliation: Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna, 148, 10154, Torino, Italy. rosanna.desiato@izsto.it.
authors.forename: Rosanna
authors.initials: R
authors.lastname: Desiato
authors.affiliation: Istituto Superiore di Sanità, Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare, Viale Regina Elena, 299, 00161, Roma, Italy. michela.tarantino@iss.it.
authors.forename: Michela
authors.initials: M
authors.lastname: Tarantino
authors.affiliation: Dipartimento di Agraria, Università degli Studi di Napoli "Federico II", Via Università 100, 80055, Portici, Italy. ambarone@unina.it.
authors.forename: Amalia
authors.initials: A
authors.lastname: Barone
authors.affiliation: Istituto Superiore di Sanità, Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare, Viale Regina Elena, 299, 00161, Roma, Italy. paolo.pasquali@iss.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pasquali
authors.affiliation: Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna, 148, 10154, Torino, Italy. pierluigi.acutis@izsto.it.
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Acutis
authors.affiliation: Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute, 2, 80055, Portici, Italy. giorgio.galiero@cert.izsmportici.it.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Galiero
mesh_terms: D000818:Animals; D002020:Buffaloes; D016022:Case-Control Studies; D002417:Cattle; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D020641:Polymorphism, Single Nucleotide; D051195:Toll-Like Receptor 2 / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics*; D014376:Tuberculosis; D014380:Tuberculosis, Bovine / Q000235:genetics* / Q000276:immunology
chemical_list: D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4