Aim: to analyze the occurrence of chronic obstructive pulmonary disease (COPD) and its association with the polymorphisms of -308G/A, -238G/A of TNF gene and +252A/G LT gene polymorphism in smokers.
Methods: cross-sectional study, comparing the genetic group of people who have COPD and who do not have COPD with the same smoking history. The study was conducted from January 2011 to March 2012 at several health centers; such as Adam Malik Hospital, Pirngadi Hospital, Tembakau Deli Hospital, Siti Hajar Hospital in Medan and several health centers in the city of Medan. Examination of lung function was done using spirometry and the existence of genetic polymorhisms in the TNF and LT gene was performed using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP).
Results: of the total of 227 samples that met inclusion criteria and after equalizing the age and history of smoking, 186 subjects were enrolled, of which, 93 people as COPD group and 93 people as non-COPD group. Analysis of the association between the -308G/A polymorphism with the COPD revealed the odds ratio (OR) 0.436 (95% CI 0.224-0.850, p=0.014). Polymorphism at -238G/A of the TNF gene showed the OR 2.094 (95% CI 0.608 - 7.211, p=0.241). Polymorphism at +252A/G LT gene showed OR 1.256 (95% CI 0.694 - 2.272; p=0.450). The findings indicated that polymorphism at -308G showed a protective factor whereas the -238G/A of the TNF and +252A/G of the LT genes did not show any significant association with the COPD.
Conclusion: polymorphism -308 TNF gene shown to be a protective factor for the occurrence of COPD. Polymorphism -238 TNF gene and +252 LT gene did not show any significant association with COPD.