RESUMO
<p><b>OBJECTIVE</b>To approach the effect of tumor necrosis factor-alpha (TNF-alpha) and tumor necrosis factor receptor II (TNFRII) gene polymorphisms on genetic susceptibility of coal worker's pneumoconiosis and their relationship with pulmonary fibrosis.</p><p><b>METHODS</b>Two hundred and thirty-four cases of coal worker's pneumoconiosis (CWP) and four hundred and forty coal mine workers (controls) were selected, and the cases of CWP were divided into three subgroups based on the various stages of I, II and III. 3 ml peripheral vein blood was drawn from every subject. Using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) techniques, TNF-alpha and TNFRII gene polymorphisms were analyzed.</p><p><b>RESULTS</b>In both group matching and 1:1 paired matching, there was no significant difference between CWP workers and controls in distribution frequencies of G/A + A/A (TNF-alpha -308) and T/G + G/G (TNFRII 196) genotypes. The distribution frequency of G/A + A/A genotype in CWP with stage III (20.00%) was higher than those in control (10.91%), and CWP cases with stage I (10.34%) and II (7.50%) respectively. The risk of CWP with stage III in those with G/A + A/A genotype was 2-fold higher than with G/G genotype (OR = 3.00, 95% CI: 0.35 approximately 25.84) for 1:1 paired matching.</p><p><b>CONCLUSIONS</b>TNF-alpha and TNFRII gene polymorphisms does not play an important role in susceptibility to CWP of Han race. TNF-alpha gene promoter polymorphisms might be related with the degree of severe pulmonary fibrosis in CWP.</p>