title: Effect of polymorphisms on TGFB1 on allergic asthma and helminth infection in an African admixed population.
abstract: Allergic asthma is a complex disorder that results from a combination of genetic and environmental factors. Studies suggest that helminth infections can activate a regulatory network characterized by the production of regulatory cytokines, such as interleukin 10 and transforming growth factor β1 (TGF-β1) and subsequently protect against immune-mediated diseases, such as asthma. On the other hand, TGF-β1 is increased in the lungs of individuals with asthma and may modulate airway inflammation. The role of TGF- β 1 single-nucleotide polymorphisms (SNPs) in allergic disease remains inconclusive.
  
  
  
  To evaluate the effects of genetic variations in the TGF-β1 on allergy and helminths infections in children.
  
  
  
  We tested for association among 4 TGF-β1 SNPs and allergic asthma, specific IgE, skin prick test result, and IL-10 production in 1,335 Brazilians. In addition, we analyzed the association with markers of helminth infection (parasite burden, anti-Ascaris IgE, and worm specific IgG4). The polymorphisms were genotyped using Taq Man probes.
  
  
  
  We found an association between rs1800470 (C allele) and atopic wheezing (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.37-0.95) and markers of allergy (OR, 0.41; 95% CI, 0.22-0.79). In contrast, a positive association was observed between the haplotype ACCA and Trichuris trichiura infection (OR, 1.85; P = .003) and Ascaris lumbricoides infection (OR, 2.01; P < .001). This haplotype was also associated with increased IL-10 production (β = 50.7; P < .001).
  
  
  
  Individuals with TGF-β1 polymorphisms have an increased susceptibility to helminth infections and a lower risk of developing allergy. These studies suggest that immune modulation of allergic disease results not only from environmental factors but also from genetic susceptibility and IL-10 production.
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland; Health Science Institute, Federal University of Bahia, Salvador, Bahia, Brazil.
authors.forename: Ryan Dos Santos
authors.initials: RD
authors.lastname: Costa
authors.affiliation: Health Science Institute, Federal University of Bahia, Salvador, Bahia, Brazil. Electronic address: cavfigueiredo@gmail.com.
authors.forename: Camila Alexandrina
authors.initials: CA
authors.lastname: Figueiredo
authors.affiliation: Public Health Institute, Federal University of Bahia, Salvador, Bahia, Brazil; Research Center Gonçalo Moniz, Fundação Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil.
authors.forename: Maurıcio Lima
authors.initials: ML
authors.lastname: Barreto
authors.affiliation: Health Science Institute, Federal University of Bahia, Salvador, Bahia, Brazil.
authors.forename: Neuza Maria
authors.initials: NM
authors.lastname: Alcantara-Neves
authors.affiliation: London School of Hygiene and Tropical Medicine, London, England.
authors.forename: Laura Cunha
authors.initials: LC
authors.lastname: Rodrigues
authors.affiliation: Center of Excellence in Asthma, Federal University of Bahia, Salvador, Bahia, Brazil.
authors.forename: Alvaro A
authors.initials: AA
authors.lastname: Cruz
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Candelaria
authors.initials: C
authors.lastname: Vergara
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Rafaels
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Cassandra
authors.initials: C
authors.lastname: Foster
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Joseph
authors.initials: J
authors.lastname: Potee
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Monica
authors.initials: M
authors.lastname: Campbell
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Rasika A
authors.initials: RA
authors.lastname: Mathias
authors.affiliation: Division of Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, Maryland; Department of Medicine, University of Colorado Denver, Aurora, Colorado.
authors.forename: Kathleen C
authors.initials: KC
authors.lastname: Barnes
mesh_terms: D000483:Alleles; D001249:Asthma / Q000453:epidemiology / Q000209:etiology*; D001938:Brazil / Q000453:epidemiology / Q000208:ethnology; D002648:Child; D002675:Child, Preschool; D005006:Ethnicity; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006373:Helminthiasis / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D016753:Interleukin-10 / Q000378:metabolism; D008297:Male; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D012882:Skin Tests; D053773:Transforming Growth Factor beta1 / Q000235:genetics*
chemical_list: C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10; D007073:Immunoglobulin E