Manganese and extracellular superoxide dismutase polymorphisms and risk for asbestosis.

Manganese and extracellular superoxide dismutases (SOD2 and SOD3) are part of the enzymatic defence against reactive oxygen species, which are involved in the pathogenesis of asbestosis. This study investigates whether SOD2Ala - 9Val and SOD3 Arg213Gly genetic polymorphisms represent risk factors for asbestosis in workers exposed to asbestos. The study included 262 cases with asbestosis and 265 controls with no asbestos-related disease. Cumulative asbestos exposure was calculated for each subject. A real-time PCR assay was introduced for genotyping. Logistic regression analysis was used to assess asbestosis risk. Asbestosis was associated with the homozygous SOD2 - 9Ala/Ala genotype (OR = 1.50, 95% CI 1.01-2.24), whereas the association for the SOD3 Arg/Gly genotype was not significant (OR = 1.63, 95% CI 0.62-4.27). The finding that the SOD2 - 9Ala/Ala genotype increases the risk for asbestosis indicates that, in addition to asbestos exposure, genetic factors may also have a significant influence on the development of asbestosis.