Heterozygosity of 198LEU mutant allele in glutathione peroxidase-1 gene as a risk factor of bronchial asthma associated with smoking

摘要

AIM: To investigate whether smoking has a differential effect by Pro198Leu genotypes of the glutathione peroxidase-1 (GPx1) gene on the risk of bronchial asthma (BA) in Russian population. MATERIAL AND METHODS: DNA samples from 195 asthmatics and 167 healthy volunteers were genotyped for Pro198Leu polymorphism of the GPx1 gene by polymerase chain reaction and restriction fragment length analysis. RESULTS: Smoking was significantly associated with an increased risk of non-allergic BA in males but not in females (p < 0.00001). When smoking was examined according to Prol98Leu polymorphism of the GPx1 gene, association of 198Pro/Leu genotype with susceptibility to allergic BA was found only in male smokers (odds ratio = 2.51, 95% confidence interval = 1.04 to 6.06, p = 0.04). CONCLUSION: The risk of allergic BA associated with smoking is increased in males who are heterozygous carriers for the low-activity 198Leu allele of the glutathione peroxidase-1 gene. The importance of molecular mechanisms is shown by which functional variants of antioxidant defense genes may mediate potentially oxidative effects of tobacco smoke on asthmatic phenotype.