The cyclooxygenase-2-765C promoter polymorphism protects against the development of chronic obstructive pulmonary disease

SummaryBackgroundSusceptibility to Chronic Obstructive Pulmonary Disease (COPD) has a genetic component. We undertook a study to determine if a genetic variant of the gene encoding the cyclooxygenase-2 gene influences the likelihood of developing COPD.MethodsIn a case control study the frequency of a single nucleotide polymorphism in the promoter region of the cyclooxygenase-2 gene (-765 G → C) was determined in 205 subjects with COPD, 171 chronic smokers with normal lung function (resistant smokers) and 95 healthy blood donors using the polymerase chain reaction and restriction enzyme fragment length polymorphism.ResultsThe frequency of the C allele of the -765 cyclooxygenase-2 polymorphism was higher in resistant smokers (24.6%) compared with subjects with COPD (14.4%, OR = 1.98, 95% CI = 1.28–3.06, p = 0.003) and blood donors (14.7%, OR = 1.97, 95% CI = 1.14–3.41, p = 0.03).ConclusionsThe -765C allele, which has been shown to be associated with decreased promoter activity of the cyclooxygenase-2 gene, is more common in resistant smokers. This raises the possibility that decreased activity of cyclooxygenase-2 may protect smokers against the development of COPD.