Association between TNF and TGF gene polymorphisms in infants and family history of allergic rhinitis and asthma

Abstract

Rationale The development and expression of allergic rhinitis and asthma may be influenced by the elaboration of specific cytokines. Cytokine gene polymorphisms moderate illness severity in a variety of inflammatory disorders. Methods Cytokine genotyping was performed on 124 infants (85% Caucasian; 57% male) to determine whether specific cytokine gene polymorphisms are associated with a parental history of allergic rhinitis and/or asthma. DNA was extracted from buccal brushings and assayed for TNF-α, IFN-γ, IL-6, IL-10 and TGF-β1 genotypes using polymerase chain reaction-sequence specific primer technology. Outcomes consisted of parental history of allergy and asthma, and results were evaluated by logistic regression. Results TNF-α and TGF-β genotypes were related to maternal and/or paternal history of allergic rhinitis and asthma, respectively. The frequencies of the genotype associated with high production of TNF-α were 41% versus 18% in infants with and without a parental history of allergic rhinitis, respectively (p<0.01). The frequencies of the genotype associated with low production of TGF-β1 were 14% versus 1% in infants with and without a parental history of asthma, respectively (p<0.01). There were no associations between IFN-γ, IL-6 and IL-10 genotypes and any of the outcome parameters. Conclusions These results suggest a role for TNF-α and TGF-β1 genotypes in the pathogenesis of allergic rhinitis and asthma, respectively. If confirmed by future studies, cytokine genotyping may be a useful tool for identifying “at risk” infants who may benefit from the selective use of preventative and/or early intervention treatments for these disorders.