More Information on Futures Steps

As outlined in both the 1996 IFBC/ILSI and the 2001 FAO/WHO decision trees, transfer of a gene known to be an allergen is unlikely to occur when the testing procedures outlined on the left side of the tree are followed. For proteins from less commonly allergenic foods or sources without any history of allergy or consumption, the results from sequence homology, gastric digestibility, processing stability and quantity of protein expressed in the plant are interpreted in context with each other to evaluate the risk of transferring an allergen. This weight-of-evidence approach has proved reliable for the rapidly digestible proteins and was endorsed by both the National Academy of Sciences (NAS, 2000) and two Joint Food and Agriculture Organization/World Health Expert Consultations (FAO/WHO 2000, 2001).

While the 1996 tree does not include animal models in the decision tree, the FAO/WHO 2001 tree does. Data on several food allergy models in the rat (Knippels et al., 1998, 1999a, 1999b, 2000; Atkinson et al., 1996; Dearman et al., 2000), mouse, (Li et al., 1999; Van Halteren et al., 1997; Hilton et al., 1997) and dog (Del Val et al., 1999; Ermel et al., 1997) as well as in vitro models (Yamanishi et al., 1997; Zafiropoulow et al., 1997; Akesson et al., 2000) have been published. None of these methods have been validated with both known food allergens and non-allergens despite their inclusion in the 2001 FAO/WHO decision tree. In the text of that report, it was acknowledged that the animal models are not validated, and that “they do not reflect all aspects of IgE-mediated food allergies in humans.” In a report by another panel of scientific experts convened by the USEPA stated:

“Although available, rodent models are not yet regarded as valid models for extrapolation to sensitization in human food allergy. It is also unlikely that any animal model will reliably predict the equivalent of human clinical reactivity.” (SAP, 2000).

The need for more research aimed at the development of validated and relevant models for food allergy in humans is acknowledged and supported by many scientists, including those from industry, government and academia.