Food Safety - The Oxford Topic of Food, Politics, and Society - page 601

What remains difficult is to predict if a protein with no history of safe use will become
a novel allergen . Molecular-structure studies are beginning to lead to an ability to predict
if a novel protein will be an allergen (Goodman, et al., 2008; Radauer, et al., 2008). There
is, unfortunately, no validated and internationally accepted animal model system with
which it is possible to predict if a protein will become an allergen; however, the search
for a predictive animal model continues.
Critics of plant genetic engineering are particularly skeptical that novel allergens
will not be introduced into crops. They often point to studies in which an allergen
from Brazil nuts was introduced into soybeans as part of a project designed to raise the
sulfur-containing amino acid content of soybeans as evidence of the dangers involved.
Researchers screened the candidate soybean extracts with serum from Brazil-nut
allergy-sensitive patients and observed a positive reaction (Nordlee et al., 1996). The
protein allergen had not been previously identified, but the safety-assessment process
detected its presence and the research was stopped in a very early stage. The experience
proves that it is, in fact, possible to introduce allergens through genetic engineering and
that it is also possible to effectively test for known or suspected allergens.
Critics also point to a study conducted by researchers in Australia who reported in
2005 that the production of a bean α-amylase in peas led to immune responses in a
rat-model system that might signify that the protein would become an allergen (Prescott
et al., 2005; Goodman et al., 2008). In spite of the fact that the rat-model system was
not widely accepted in the scientific community, CSIRO10 discontinued the research.
In a recent publication, these, together with other investigators, were unable to confirm
the previously reported results and observed no difference in immune response of rats
between exposure to control or experimental peas (Lee et al., 2013).
Food allergy is a very important and emotional issue. There is an especially large
amount of misinformation with regard to the potential for transgenic crops to cause
allergy. Perhaps the worst of these is the claim that since the introduction of GM soy-
beans in 1996 the rate of food allergy has doubled (Smith, 2007). This is a classic example
of a post hoc fallacy in which there is no causal connection demonstrated.
Rat Studies: What They Can and Can't
Tell Us
All chemicals are poisons; it is only the dose that makes that a thing is not
a poison . . .
—Paracelsus (1493-1541)
Toxicologists rely heavily on studies in animals to assess toxicity of chemical com-
pounds. The 90-day chronic-toxicity animal study in which various fixed amounts of
a compound to be tested are administered each day to determine a dose-response curve
has become a standard for evaluating the maximum dose at which no adverse effects are