HPGDS and colonic neoplasm: Since genetic polymorphisms of enzymes such as glutathione S-transferases (GSTs) have been shown to have an important role in detoxifying foreign substances from tobacco smoke, influencing susceptibility to both lung and colon cancer [11], [12] it is tempting to speculate that such polymorphisms may be of importance also for the development of RA, and that such influences may be very complex [13].