ABSTRACT
Bronchial asthma (BA) is increasing among Egyptian children. It is affected by multiple factors including genetic ones. In the current study, we assessed the relationship between interleukin-17 (IL-17) genotypes and the occurrence of BA among Egyptian children. This case-control study included 100 participants. Group I (the control group) comprised 50 healthy subjects. Group II (the asthmatic group) comprised 50 subjects diagnosed with atopic asthma according to the Global Initiative for Asthma. Measurement of serum Ig E and eosinophilic count was performed. Detection of single nucleotide polymorphism rs2275913 of IL-17 gene by restriction fragment length polymorphism-polymerase chain reaction was conducted. GA and AA genotypes were more frequent in the asthmatic group compared to the control group (P = 0.03 and 0.01, respectively). Subjects carrying GA and AA genotypes were more susceptible to have asthma [odds ratio (OR) = 2.21, 95% confidence interval (CI) = 1.14-9.94, P = 0.03; OR = 7.78, 95% CI = 1.59-38.3, P = 0.01, respectively]. The A allele was higher in the asthmatic group (33%) compared to the control group (10%). A allele carriers were more susceptible to have asthma (OR = 4.43, 95% CI = 2.04-9.82 and P < 0.001). Immunoglobulin E (IgE) levels and eosinophil percentages were higher among the carriers of GA and AA genotypes when compared with the GG genotype. All pulmonary function tests were significantly lower among carriers of AA genotype compared with GG genotype. An A allele carrier, AA genotype, increased IgE level, and eosinophil level were significant predictors for occurrence of asthma (P = 0.01, 0.02, 0.004, and 0.01). In conclusion, AA genotype carriers and A allele carriers of the IL-17 gene are more likely to have asthma compared with controls.