3.1—GM soybeans are no more allergenic than conventional soybeans
Scientists ensure that GM soybeans don’t cause allergies
Analysis of Peer-Reviewed Research:
The story about the Brazil nut allergen that was transferred into soybeans by genetic engineering is offered as proof by Smith that GM technology could be used to transfer an allergen to a food. To reinforce his case he argues that it is hard to detect such potential allergens because if scientists had taken serum from people who weren’t Brazil nut allergy sufferers, they would have missed the potential allergen. In his zeal to criticize GM crops, Smith completely misses, or intentionally obscures, the point. Brazil nut allergy sufferers are always selected when testing for potential Brazil nut allergens because they are known to have antibodies to those allergens in their blood while normal subjects will not have them—that’s the way the allergy works. Smith also obscures the fact that researchers were able to detect the potential problem in the early stages of development. Nobody wants food that causes allergies and this story demonstrates that we have robust scientific methods to ensure that doesn’t happen. It should be told as a scientific success story that should reassure consumers that GM foods won’t cause allergies. It should also be mentioned that researchers strongly avoid using genes isolated from organisms to which humans are known to be allergic.
1. Developers understand the need for safety testing. It is well established that almost all food allergens are proteins—and we know that proteins are encoded by genes (Mills and other 2004). It was therefore obvious that if a gene is taken from a plant to which people are allergic, one should be careful that an allergen has not been transferred. When Pioneer started this project the protein they selected was not known to be a potential allergen. Nonetheless, they asked food allergists to evaluate the safety of their nutritionally-enhanced soybean (Nordlee and others 1996). It is important to note here that evaluating the potential for allergenicity is a required step in the pre-market safety assessment process (Lehrer and Bannon, 2005).
2. It is not difficult to determine if a protein is a known food allergen. Scientists can evaluate the sequence of a protein to determine if it resembles any known allergen. If a protein comes from a plant that causes allergies, or if it resembles an allergen, researchers can test if allergy antibodies in serum samples from allergy sufferers react with the protein—if the protein react positively with allergy-associated antibodies, it is concluded that it may be an allergen since false positives can also occur. Scientists can also do tests to determine if antibodies are present in allergic serum that bind to a protein of the same size as the known allergen. This provides further evidence since it is unlikely that another protein of exactly the same size will give a false positive test. Skin prick tests with allergic subjects can be used to confirm that the protein reacts in humans. These are exactly the tests performed by food allergy specialists in this case (Nordlee and others 1996). Because they observed positive results, they cautioned the developer that they had probably transferred a previously undescribed food allergen to the soybean. The conclusion to be drawn is that scientists have developed very reliable methods with which they can identify food allergens.
3. The developer terminated the project. The purpose of safety testing is to evaluate if a product will be safe for consumers (Lehrer and Bannon 2005; Goodman and others 2008). In this case, when it became clear that the transferred protein with potentially an allergen—remember nobody has ever eaten this soybean or suffered an allergic reaction—the project was stopped. The soybean never made out of early stages in development; it was never submitted to regulators nor was any attempt ever made to market it. This is exactly how the premarket safety assessment is supposed to help developers ensure that only products that are as safe as any other food reach the market. It is a fact that no GM product has ever caused a food allergy (Goodman and others 2008). Ironically, about 10 common foods cause over 95 percent of all food allergies (Bannon and Lehrer 2005). No premarket testing is required for non-GM foods and they are not taken off the market when they cause allergies.
4. The premarket safety system protects the consumer and the producer. Companies do not benefit from selling defective products that make consumers sick, and consumers don’t want tainted products. The premarket safety evaluation that is applied to GM crops, but not conventional crops or organic products, has little difficulty detecting known food allergens.
Goodman RES, Vieths S, Sampson HA, Hill D, Ebisawa M, Taylor SL and van Ree, R. (2008). Allergenicity assessment of genetically modified crops: what makes sense? Nat. Biotech. 26: 73-81.
Lehrer SB and Bannon GA (2005). Risks of allergic reactions to biotech proteins in foods: perception and reality. Allergy, 60: 559–564
Mills ENC, Jenkins JA, Alcocer MJC and Shewry PR (2004). Structural, biological, and evolutionary relationships of plant food allergens sensitizing via the gastrointestinal tract. Critical Reviews in Food Science and Nutrition, 44:379–407
Nordlee JA, Taylor SL, Townsend JA, Thomas LA and Bush RK (1996). Identification of a Brazil-nut allergen in transgenic soybeans. N. Engl. J. Med., 334:688–92.
A gene from a Brazil nut carried allergies into soybeans
- A gene from a Brazil nut was inserted into soybeans
- When tests verified that people allergic to Brazil nuts would react to the GM soy, the project was canceled.
- This research verified that genetic engineering can transfer allergenic proteins into crops
A gene from a Brazil nut was transferred into soybean and routine safety assessment found that serum from people with Brazil nut allergies gave a positive reaction.