Association of <i>MnSOD</i> and <i>GPX1</i> gene polymorphisms with a risk of chronic dust-induced bronchitis

Abstract

Aim. To assess the association of the MnSOD (rs4880) and GPX1 (rs1050450) gene polymorphisms with a risk of developing chronic dust-induced bronchitis in workers of the coal mining industry. Materials and methods. The study included 182 coal miners with prolonged exposure to high concentrations of coal dust, including 116 people with a previously established diagnosis of chronic dust-induced bronchitis (CDB) and 66 people without pathology of the bronchopulmonary system, working under the same sanitary and hygienic conditions. Polymorphisms of the MnSOD (rs4880) and GPX1 (rs1050450) genes were studied using polymerase chain reaction. Results. For the first time, we established a statistically significant association between the polymorphisms of the MnSOD (rs4880) and GPX1 genes (rs1050450) and CDB. Thus, the chance of detecting the homozygous A/A (Val/Val) MnSOD genotype in miners with CDB was 2 times higher than in the comparison group ( χ 2 – 5.42; р = 0.02; odds ratio (OR) 2.21; 95% confidence interval (CI) 1.13–4.33), while the chance of detecting the homozygous G/G (Pro/Pro) GPX1 genotype in miners with CDB was almost 6 times higher than in the comparison group (χ2 – 21.47; р = 0.001; OR 5.89; 95% CI 2.65–13.08). It was found that the combination of AA/GG genotypes of the MnSOD / GPX1 genes was significantly associated with a 1.5-fold risk of developing CDB (χ 2 – 11.49; р ˂ 0.001; relative risk (RR) 1.59; 95% CI 1.36–1.84), while the chance of detecting this combination of genotypes in miners with bronchopulmonary pathology was 15 times higher than in the comparison group (OR 15.09; 95% CI 1.99–114.64). Conclusion. Carriage of homozygous genotypes A/A at the rs4880 MnSOD locus and G/G at the rs1050450 GPX1 locus was shown to be a marker of genetic predisposition to the development of CDB. The combination of homozygous genotypes of the studied AA/GG MnSOD / GPX1 genes indicated a 1.5-fold risk of developing CDB. Carrying one of the three combinations of the MnSOD and GPX1 genotypes (GG/AA, AA/AA, and AG/AA) indicated resistance to the development of CDB.