Toll-like receptor 2 as a major gene for asthma in children of European farmers

Waltraud Eder, Walt Klimecki, Lizhi Yu, Erika Von Mutius, Josef Riedler, Charlotte Braun-Fahrländer, Dennis Nowak, Fernando D. Martinez

Research output: Contribution to journalArticlepeer-review

415 Scopus citations


Background: The finding that the prevalence of asthma and allergies Is less frequent in children raised on animal farms has led to the conjecture that exposure to microbial products modifies immune responses. The toll-like receptors (TLRs) represent an evolutionarily conserved family of innate immunity receptors with microbial molecules as ligands. Objectives: We reasoned that polymorphisms in genes encoding TLRs might modulate the protective effects observed in farming populations. Methods: Farmers' and nonfarmers' children living in rural areas in Austria and Germany and who were enrolled in the cross-sectional ALEX study were genotyped for single nucleotide polymorphisms in the TLR2 and TLR4 genes. The frequencies of asthma, allergic rhinitis, and atopic sensitization were compared between the genotypes in relation to exposure to farming and endotoxin. Results: Among farmers' children, those carrying a T allele in TLR2/-16934 compared with children with genotype AA were significantly less likely to have a diagnosis of asthma (3% vs 13%, P = .012), current asthma symptoms (3% vs 16%, P = .004), atopic sensitization (14% vs 27%, P = .023), and current hay fever symptoms (3% vs 14%, P = .01). The association between TLR2/-16934 and asthma among children of farmers was Independent of atopy. No such association was found among children from the same rural communities but not living on farms. Conclusion: Our results suggest that genetic variation in TLR2 is a major determinant of the susceptibility to asthma and allergies in children of farmers.

Original languageEnglish (US)
Pages (from-to)482-488
Number of pages7
JournalJournal of Allergy and Clinical Immunology
Issue number3
StatePublished - Mar 2004


  • Asthma
  • Atopy
  • Children
  • Endotoxin
  • Farming
  • Gene-environment interaction
  • TLR2
  • TLR4

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology


Dive into the research topics of 'Toll-like receptor 2 as a major gene for asthma in children of European farmers'. Together they form a unique fingerprint.

Cite this