p53 mutations in lung cancer associated with residential radon exposure

Unusual mutation patterns in lung tumors among underground miners have been indicated, suggesting radon-specific alterations in the genome, but the da ta are not consistent. To investigate the association between residential r adon exposure and p53 mutations in lung tumors, we performed a study on cas es from a nationwide population-based investigation in Sweden, Our study in cluded 83 nonsmoking lung cancer cases and 250 smoking lung cancer cases, d iagnosed 1980-1984, with a time-weighted average radon exposure over 140 Bq /m(3) or up to 50 Bq/m(3). Radon was measured in dwellings occupied by the study subjects at some time since 1947, Information on smoking habits and o ther risk factors was obtained from questionnaires. After exclusions becaus e of the initiation of treatment or insufficient material, the p53-status o f 243 tumors was determined using PCR-single-stranded conformation polymorp hism analysis and sequencing determination of exons 5-8, The overall mutati on prevalence was 23.9%. An increased mutation prevalence was suggested amo ng those with high exposure to residential radon [odds ratio (OR), 1.4; 95% CI, 0.7-2.6], especially among nonsmokers (OR, 3.2; 95% CI, 0.7-15.5), but no specific mutational pattern was indicated. Furthermore, the mutation pr evalence seemed to be higher among smoking lung cancer cases than among non smoking cases (OR, 2.1; 95% CI, 0.9-5.0), and particularly among those smok ing less than 10 cigarettes per day. It may be concluded that residential e xposure to radon seems to contribute to a higher mutation prevalence of the p53 gene in lung tumors.