RESUMEN
The discrepancy between what the general public and specialist in allergic diseases regard as a true food allergy can in part depend on the frequent evidence of subjects in whom clinical symptoms elicited by a given food allergen are frequently not reproducible: this suggests the existence of allergens variably present in certain foods. In adults and older children common is a form of food allergy associated with inhaled allergens, especially pollens. In this allergic form pollens and various vegetal food often cross react but the underlying scientific rationale is largely unclear. From the study of the "latex-fruits allergic syndrome" and the "oral allergic syndrome" emerged that the cross reactivity depends on epitopes of pollens and vegetables belonging to one of the 14 classes of the "pathogenesis related proteins" (PRPs). Vegetables produce PRPs in response to infection or after plant injury or application of chemicals: long-term conservation and methods used for rapid artificial ripening of vegetables can cause plant to produce PRPs or other allergens. A genetic selection of vegetables "protecting themselves against infection and infestation" by mean of PRPs production is practiced in agroalimentary biotechnology. We deem it urgent that the two realms, Medical Science (Allergology) and Agricultural Biotechnology begin to communicate openly in order to produce food as efficiently as possible but without harming the large part of the population which is predisposed to allergy and react to PRPs.