PURPOSE: A polymorphism of TNF-α has been reported, but inconsistent results may arise from different populations of COPD. This research was conducted to study the TNF-α polymorphisms and to investigate the association between genetic polymorphisms and levels of TNF-α in the sputum.
METHODS: 25 COPD patients and 13 controls were recruited. Genomic DNA was used as a template for amplification by PCR to determine the TNF-α polymorphism. The products were investigated by auto-sequencing analysis. The level of TNF-α in induced sputum was measured by ELISA.
RESULTS: The levels of TNF-α were significantly increased in sputum of COPD patients(53.410.7pg/
) as compared with control subjects(19.711.9pg/). The level of TNF-α in induced sputum was inversely correlated with FEV1 (r= −0.42, p=0.008). The frequencies of GG genotype in the TNF-α gene promotor region were 88.0%(22/25) in the COPD and 84.6%(11/13) in the controls. The frequencies of GA genotype in the TNF- gene promotor region were 12.0%(3/25) in the COPD and 15.4%(2/13) in the controls. There was no association between TNF- polymorphism and TNF- levels of sputum.
CONCLUSION: The level of the TNF-α was markedly increased and inversely correlated with airflow obstruction. Although it has been speculated that TNF-α might have a causal relationship with COPD,TNF-α gene promoter polymorphism does not seem to play a major role as genetic risk factor in Korean COPD.
CLINICAL IMPLICATIONS: However, we cannot exclude that other mutations in the TNF gene complex may play a role. Further study in association with mutations in other genes will be needed.
DISCLOSURE: Sung Chul Lim, No Financial Disclosure Information; No Product/Research Disclosure Information