There Is No Evidence of Difference in Polymorphisms in the IL-1 β -511 Promoter and IL-1Ra Gene Between Asthmatic and Healthy Groups

Asthma is a chronic inflammatory disease of the airway. Both genetic and environmental factors are thought to be involved in the onset of the disease. We aimed to investigate if the interleukin-1β (IL-1β)-511 promoter and IL-1 receptor antagonist (IL-1Ra) gene polymorphisms could be used as markers of susceptibility to bronchial asthma in children. Children were divided into two groups: (1) bronchial asthma (n = 202) and (2) healthy control (n = 144). Polymorphisms for the IL-1β-511 promoter and IL-1Ra were detected by polymerase chain reaction. Genotypes and allelic frequencies for these polymorphisms in both groups were compared. The difference in the proportions of different IL-1β-511 promoter and IL-1Ra polymorphisms in both groups were not significant. Proportions of C homozygote/heterozygote/T homozygote for IL-1β-511 promoter were (1) 34.2/46.0/19.8% in the asthma group and (2) 33.3/48.6/18.1% in the control group. Alleles I/II/III/IV for IL-1Ra were (1) 91.8/7.7/0.5/0% in the asthma group and (2) 90.3/9.4/0/0.3% in the control group. There was no association of pediatric asthma with the IL-1β-511 promoter and IL-1Ra gene polymorphisms. These polymorphisms are not useful markers for prediction of asthma susceptibility.