COMBINATIONS OF SUSCEPTIBLE GENOTYPES AND INDIVIDUAL-RESPONSES TO TOXICANTS

The variation in individual responses to exogenous agents has been sho wn to be exceptionally wide. It is because of this large diversity of responsiveness that risk factors to environmentally induced diseases h ave been difficult to pinpoint, particularly at low exposure levels. O pportunities now exist for studies of host factors in environmentally induced cancer or other diseases in which an environmental component c an be presumed. Many of the studies have shown an elevated disease pro neness for individuals carrying the potential at-risk alleles of metab olic genes, but a number of controversial results have also been repor ted. One possible explanation for the divergent findings is lack of kn owledge of the other potentially relevant genotypes for a given exposu re, This paper gives an overview of the published data on combinations of metabolic genotypes in relation to individual susceptibility to en vironmental toxicants.