[The genetics of chronic obstructive pulmonary disease]

COPD is a heterogenous disease caused by the interaction of genetic susceptibility and environmental influences. The best example to support this is tobacco smoke. Although cigarette smoking is the most important aetiological factor, only up to half of chronic smokers develop significant COPD. There are three main themes within the pathogenesis of COPD: 1) imbalance between proteases and anti-proteases, 2) oxidative stress, 3) inflammation. Disparity between levels of exogeneous oxidants, e. g., tobacco smoke, and endogeneous antioxidants leads to oxidative stress which, in turn, causes an inflammatory response involving pro-inflammatory mediators. The activated inflammatory cells release further proteases and oxidants, leading to chronic inflammation and irreversible destruction of connective tissue in the lung. Individual genetic variations influence these processes in many ways. This article summarises the results of recent candidate gene studies for COPD.