Interactions between traffic air pollution and glutathione S-transferase genes on childhood asthma

AIM: To evaluate the role of glutathione S-transferase P1(GSTP1) genetic polymorphisms potentially modifying the association between NO2 and asthma/wheeze in Taiwanese children. METHODS: We investigated 3714 schoolchildren in Taiwan Children Health Study from 14 communities. Children’s information was measured from questionnaire by parents. The traffic air pollutant was available from Environmental Protection Administration monitoring stations. RESULTS: A two-stage hierarchical model and a multiple logistic regression model were fitted to estimate the effects of NO2 exposures and GSTs polymorphisms on the prevalence of asthma and wheeze. Among children with GSTP1 Ile/Val or Val/Val genotypes, those residing in high-NO2 communities had significantly increased risks of asthma(OR = 1.76, 95%CI: 1.15-2.70), lateonset asthma(OR = 2.59, 95%CI: 1.24-5.41), active asthma(OR = 1.93, 95%CI: 1.05-3.57), asthma under medication(OR = 2.95, 95%CI: 1.37-6.32) and wheeze(OR = 1.54, 95%CI: 1.09-2.18) when compared with children in low-NO2 communities. Significant interactions were noted between ambient NO2 and GSTP1 on asthma, late-onset asthma, asthma under medication and wheeze(P for interaction < 0.05). However, we didnot find any association with polymorphisms in GSTM1 and GSTT1. CONCLUSION: Children under high traffic air pollution exposure are more susceptible to asthma, especially among those with GSTP1 Val allele.