Polymorphisms in nucleotide excision repair genes, smoking and intake of fruit and vegetables in relation to lung cancer.

Polymorphisms in nucleotide excision repair genes have been associated with risk for lung cancer. We examined gene-environment interactions in relation to lung cancer in 430 cases and 790 comparison persons identified within a prospective cohort of 57,053 persons. We included polymorphisms in the XPC, XPA and XPD genes involved in the nucleotide excision DNA repair pathway and analysed possible interactions with smoking and dietary intake of fruit and vegetables in relation to risk for lung cancer. We found that intake of fruit was associated with lower risk for lung cancer only among carriers of the XPA A23G variant genotype. The incidence rate ratio for lung cancer was 0.60 (95% confidence interval: 0.43-0.84; p=0.003) per 50% increase in fruit intake. No convincing interactions were detected between the polymorphisms and smoking.