RESUMEN
Working Group 3 (Sensitivity to Organic Dusts-Atopy and Gene Polymorphisms) was convened to review the current understanding of how effects of inhaled organic dust may be modified by genetic factors-both those that increase as well as those that may reduce susceptibility. Furthermore, the group was asked to suggest areas that require more investigation in this field. The discussion focused on individual sensitivity to inhaled agents as the most important determinant of inter-individual heterogeneiety in responses to exposures. Genetic modifiers are known for a number of pathologic conditions (including asthma, atopy, chronic obstructive pulmonary disease, and hypersensitivity pneumonitis) associated with inhalation of organic dusts; modifiers are likely to be identified for a number of other disease states. Further studies are required to delineate more precisely the contribution (and the role in inflammatory cascade modulation) of these known polymorphisms, as well as to identify novel genetic factors.