Antithetical effect of tumor necrosis factor-αgene polymorphism on coal workers' pneumoconiosis (CWP)

Inter-individual variation in the severity of pneumoconiosis has been described, even with the same environmental exposure. We hypothesized that TNF-alpha promoter polymorphisms associate with lung responses to environmental exposure in coal worker's pneumoconiosis (CWP) patients. We examined polymorphisms at -238, -308, and -376 in 124 patients with CWP who had similar dust exposure history and in 122 non-exposed controls. CWP patients were divided into two groups: (1) nodular CWP (n = 84): (2) progressive massive fibrosis (PMF) (n = 44). The -308 A allele frequency was higher in patients with CWP compared to controls (6.35% and 2.05%, P {lt} 0.01). It was also higher in patients with nodular CWP compared to PMF (P {lt} 0.05). Logistic regression analysis revealed that patients with the -308 A allele were 3.8 times (P = 0.036) and those with smoking habit were 2.3 times (P {lt} 0.002) more likely to have nodular CWP than PMF. Thus TNF-alpha-308 A allele might interact with smoking to enhance susceptibility to nodular CWP.