Relation of Interleukine-۴ (C-۵۸۹T) and Interferon-gamma (A+۸۷۴T) Allele polymorphism with Asthma

Background and Objective: Asthma is a common respiratory disease caused by acute and chronic bronchial inflammation. Clinical manifestations of the disease are closely related to genetics. IL-۴ is a cytokine of TH۲ lymphocytes, polymorphism in prompter region, C-۵۸۹T, is associated with IL-۴ production, while IFN-γ, is a cytokine of TH۱, and A+۸۷۴T polymorphism in interon ۱ of IFN-γ is associated with it’s production and release. Cytokine gene polymorphisms could influence pathogenesis of asthma with TH۱/THh۲ ratio, being of great importance. Materials and Methods: ۸۱ unrelated asthmatic patients were selected according to ATS characteristics and separated into two groups of controlled and uncontrolled asthma. ۸۰ normal subjects were chosen as control group. After collection of peripheral blood and DNA extraction, PCR-RFLP method was used for genotyping of IL-۴, -۵۸۹ position. For evaluation of polymorphism in +۸۷۴ position of IFN-γ ARMS-PCR method was used. Results: Distribution of frequency of IFN- (A+۸۷۴T) and IL-۴(C-۵۸۹T) polymorphisms didn’t show any statistically significant difference between two patient groups and healthy control group (p≥۰.۰۵). There was neither any significant difference (p≥۰.۰۵) among other parameters. Conclusions: Studies in field of cytokine polymorphism have had variable results. So many studies have mentioned a relationship between cytokine gene polymorphism and susceptibility and/or severity of asthma and some studies have shown that there is no association between these factors we believe that there may exist factors different from IL-۴ and IFN-γ polymorphism which coner the effects of these genetic vaciants in pathogenesis and severity of asthma.

Keywords:

Key words: Astham , IL-۴ , IFN-γ , Polymorphism