Genotyping of IL-4 -590 (C>T) Gene in Iraqi Asthma Patients

Abstract

This study is the first investigation in Iraq dealing with genotyping of IL-4 -590 (C>T) gene, especially in Iraqi patients with asthma. We studied forty-eight blood samples collected from patients with asthma and compared with age-matched 25 healthy individuals as controls. The polymorphism results of IL-4 -590 (C>T) gene by using amplification refractory mutation system (ARMS-PCR) showed the presence of C and T alleles and three genotypes (CC, CT, and TT). Interestingly the frequency of C allele and CC genotype was higher in patients with asthma in comparison with the same allele and genotype in control (P 1 × 10-6). This increase was associated with an increased risk factor of asthma (odds ratio [OR] 9.21; 95% confidence interval [CI] 3.58-23.71). Genotypes analysis by using Hardy-Weinberg distribution showed no significant differences between patients with asthma and healthy subjects. In conclusion, the increasing risk of asthma was associated with C allele and the CC genotype and these are revealed as etiological fraction with risk by having this disease, while the T allele percentage ratio in controls was higher when it is compared with asthma patients suggesting that these alleles have a protective effect (preventive fraction).