Study of IL5, IL1 and TNFα genes polymorphisms in the predisposition to chronic polypoid rhinosinusitis
Background: Chronic rhinosinusitis (CRS) is a common disease of the nose and paranasal sinuses with a protracted, relapsing course, whose treatment is often ineffective. Two forms of chronic rhinosinusitis are known: chronic bacterial rhinosinusitis and chronic polypoid rhinosinusitis (СPRS). CPRS is a multifactorial disease which is often associated with asthma and allergic rhinitis, but the mechanisms of these pathologies appearance with the nasal polyposis are still not clear. Therefore, additional studies to understand the pathophysiological features of CPRS are more relevant today. The aim of the study:To study the relationship of polymorphic variants of TNFα, IL1, and IL5 cytokine genes with the risk of developing chronic polypoid rhinosinusitis. Materials and methods:100 patients with chronic polyposis rhinosinusitis and 100 healthy individuals were examined at the ENT department of Kursk Regional Clinical Hospital and at the ENT department of Kursk City Hospital No. 1 named after N.S. Korotkov from 2010 to 2012 years. All patients were sampled venous blood from the cubital vein in 5 ml tubes with 0.5 ml of 0.5 M EDTA (pH = 7.8), after which the genomic DNA was isolated by a standard phenol-chloroform extraction method. Genotyping of polymorphic variants of genes was carried out by polymerase chain reaction (PCR) methods. The processing of PCR products was carried out by specific restriction enzymes according to the protocols described by the enzyme producers. Restriction of the amplified fragments was performed with 5-10 U endonucleases. The Chi-square Pearson test was used to assess the correspondence between genotype distributions and the comparison of genotype frequencies in samples of patients and healthy people. The association of genotypes with a predisposition to polypous rhinosinusitis was judged by the magnitude of the odds ratio. Results:It was established that the genotypes G/A - A/A of TNFα gene (OR = 2.00, 95% CI 1.12-3.59, p = 0.02) and the C/T genotype of IL5 gene (OR = 0.53, 95 % CI 0.30-0.95, p = 0.03) are associated with a risk of developing CPRC. The sex-stratified analysis showed that the G/A genotype of TNFα gene is associated with CPRS development in women (OR = 3.54, 95% CI 1.28-9.80, p = 0.02). Conclusion:Polymorphic variants of the TNFα and IL5 cytokines genes are significant predictors in assessing predisposition to chronic polypoid rhinosinusitis.