Association of Gene Polymorphisms in Interleukin 6 in Infantile Bronchial Asthma.

Introduction: The genetic background of bronchial asthma is complex, and it is likely that multiple genes contribute to its development both directly and through gene-gene interactions. Cytokines contribute to different aspects of asthma, as they determine the type, severity and outcomes of asthma pathogenesis. Allergic asthmatics undergoing an asthmatic attack exhibit significantly higher levels of pro-inflammatory cytokines, such as interleukins and chemokines. In recent years, cytokines and their receptors have been shown to be highly polymorphic, and this prompted us to investigate interleukin 6 promoter polymorphisms at position -174G/C (rs1800795) and at -572G/C (rs1800796) in relation to asthma in children.
Methods: Interleukin 6 promoter polymorphisms were analyzed in bronchial asthma patients and healthy children using polymerase chain reaction-restriction fragment length polymorphism analysis.
Results: We observed a significant association between polymorphism at -174G/C and bronchial asthma (OR=3.4, 95% CI: 2.045-5.638, P<.001). Higher associations between polymorphism at IL-6 -174G/C and bronchial asthma were observed in atopic patients (OR=4.1, 95% CI: 2.308-7.280, P<8.10 ^-7 ).
Conclusions: Interleukin 6 polymorphism is associated with bronchial asthma, particularly its atopic phenotype. Expression and secretion of interleukins in asthmatic patients may be affected by genetic polymorphisms, and could have a disease-modifying effect in the asthmatic airway and modify the therapeutic response.
(Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.)