Gene polymorphisms of tumor necrosis factor alpha−308 and interleukin-10−1082 among asthmatic Egyptian children

Abstract

Tumor necrosis factor (TNF) alpha-308 and interleukin (IL)-10(-1082) have potent inflammatory responses in the process of airway inflammation in asthma. The purpose of this study was to check for association of polymorphisms related to cytokine genes with susceptibility and severity of bronchial asthma in Egyptian children. Blood samples of 69 asthmatic children receiving treatment and follow-up at the Allergy and Respiratory Medicine Unit, Mansoura University Children Hospital, Mansoura, Egypt, were subjected to DNA extraction and amplification using polymerase chain reaction with sequence-specific primers for detection of single nucleotide polymorphisms in the promoter regions of cytokine genes TNF-alpha(-308(G-->A)), IL-10(-1082(G-->A)). Compared with normal controls, Egyptian asthmatic children showed a significant higher frequency of IL-10(-1082) G/G homozygosity genotype (p < 0.001; odds ratio [OR] = 7) with lower frequency of G/A heterozygosity genotype among cases. This finding also was detected in cases with persistent asthma and eczema. These cases showed significant lower frequency of TNF-alpha-308 G/A heterozygosity (p < 0.05; OR = 0.44). Also, male cases, cases with positive family history, and those patients with persistent types of asthma showed a higher frequency of TNF-alpha-308 G/G homozygosity. IL-10(-1082(G-->A)) G/G and TNF-alpha-308(G-->A) G/G may be a contributing factor in susceptibility as well as severity of asthma among Egyptian children. Separate studies should be specified relating these cytokine genotypes to response to various modalities in asthma therapy. This study reports that IL-10(-1082(G-->A)) G/G and TNF-alpha-308(G-->A) G/G genotypes may be contributing factors in susceptibility as well as in severity of asthma among Egyptian children. Separate studies may be specified relating these cytokine genotypes to response to various modalities in asthma therapy.