Association of Interleukins 17A and 17F Gene Polymorphism with Asthma: A Case Control Study in North Indian Population

The number of cases of asthma patients has been on rise globally due to several factors. The available scanty information concerning attributes of certain genes in asthma’s pathophysiology is a blockade in its early diagnosis and treatment. The objective of present study was to investigate roles of IL-17A and IL-17F in occurrence and severity of asthma in North Indian population. This study involved 150 cases with asthmatics and 150 healthy controls. Asthmatic patients were confirmed by Spirometry and other clinical parameters. The genotype frequencies observed for all genes in controls were in Hardy Weinberg Equilibrium (HWE). The results suggested that the asthmatics of the same height and age had lower weight and higher smoking rate in comparison to controls. The asthmatics displayed cough, breathlessness, congestion, disturbed sleep, headache, and wheezing. These parameters were found to be significantly elevated in asthmatics. Excepting Hb, levels of blood eosinophils, AEC, TLC and serum IgE were higher in cases than controls. The lower serum IL-17F and IL-17A levels were recorded in asthmatics. In IL-17F, rs 2397084 and rs763780 mutants and variant genotypes were found to be increased in cases than in controls. In rs 2397084 CC, CT + CC was significantly higher in cases. Also, rs763780 mutant and variant genotypes were significantly higher in cases. In contrast, IL-17A rs2275913 showed hetero GA variant GA + AA significantly higher in cases. The rs3748067 indicated variant GA + AA to be non-significantly higher in cases. The RFLP analysis of certain regions in IL17F and IL17A genes and increased IL-17A and IgE levels in the blood of asthmatics have generated evidences to indicate that these markers might be playing key roles in onset and severity of asthma. These indices may therefore be exploited for timely diagnosis and adequate management of asthma.