Association Between Gene Polymorphism of IL13/IL-Rα Signaling Pathway and Severity of Bronchial Asthma

Abstract

Aim (<strong>background): Asthma is one of the most common chronic inflammatory lung diseases worldwide. Its incidence and mortality are increasing among children and its impact on society is substantial Different genes are associated with categorical classifications of asthma severity. However, continuous outcomes should be used to catch the heterogeneity of asthma phenotypes and to increase the power in association studies. The aim of our work is to investigate whether there is association between single nucleotide polymorphism (SNPs) in 3 candidate genes of IL-13/IL-4Rα signaling pathway and the severity of bronchial asthma. Patients and Methods: Sixty subjects were enrolled in this study divided into 3 main groups: healthy control group (20 subjects), patients with severe bronchial asthma (20 subjects) and patients with mild bronchial asthma (20 subjects). IL-13 C1923T, IL-4 C–590T and IL-4 R 175 were assessed using RFLP. Results: Results revealed that polymorphism of IL-13 C1923T genotypes and T allele as well as polymorphism of IL-4 R 175V genotypes and G allele are correlated to severity of asthma on one hand and with smoking status of patients on the other hand. Conclusion These data suggest that genetic variants in IL-13/IL-4Rα signaling pathway may be involved in the development of severe asthma. In addition, a new pattern of biological interaction that affects the severity of asthma is described between SNPs of both IL-13 C1923T and IL-4 R 175 and smoking.