Allergenicity

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Issue in Brief:
Biotechnology Products Are Tested for Allergenicity

One of the major food safety concerns raised in connection with agricultural biotechnology is the issue of allergenicity. No approved biotech product has been found to be allergenic, and federal regulatory and international organizations have concluded that these products pose little or no risk to people with food allergies.

Food allergies are triggered when the immune system responds to certain proteins in foods. There are many foods that contain allergenic proteins, the main sources being tree nuts, peanuts, soybeans, milk, eggs, fish, crustaceans and wheat.

While virtually all known food allergens are proteins, only a very small number of food proteins are allergens. As genes "code" for proteins, the addition of a new gene, no matter its source, to a crop plant using biotechnology could potentially introduce an allergen, though the risks of this happening are quite low.

Although the chance that a new gene will introduce an allergen is extremely small, the products of biotechnology still go through a battery of tests to ensure that allergens are not present. This is especially the case when the transferred gene comes from a known allergen source.

In the 1990s, one biotech firm tried to improve the protein content of a soybean variety by transferring a gene from the Brazil nut. Subsequent testing showed that this gene encoded for an allergen, and development of the project was halted. Often cited as an example of what can go wrong, it actually demonstrates how good testing according to scientific protocols can ensure safety.

It is Food and Drug Administration policy that when genetic material from a known allergenic source is transferred to a new plant variety, the plant developer should assume that it encodes for an allergen until it can be conclusively shown otherwise. Also, new products including genetic material from known allergens must be labeled to that effect so that consumers susceptible to allergies can make informed choices. Biotechnology companies avoid using genetic material from known allergen sources.

The Environmental Protection Agency also has a regulatory role in ensuring that pest-protected plants do not pose a risk to allergy-susceptible individuals. EPA's October 2000 reregistration action document for Bt crops considered potential allergenicity and determined that these crops pose little, if any, risk.

For more on U.S. regulation of biotech crops and foods, click here.

Moreover, a number of scientists and organizations-such as the joint work of the U.N. Food and Agriculture Organization and World Health Organization, the International Food Biotechnology Council, and the Allergy & Immunology Institute of the International Life Science Institute (Metcalfe et al.) -have developed scientific protocols to assess the potential allergenicity of new foods. These protocols include the source of the genetic material, the structure of the new protein compared with known allergens, the reactivity of the protein with antibodies from individuals with known allergies, and the digestive stability of the protein.

An advantage of using biotechnology is that the number of genes being transferred from one organism to another is limited. This allows scientists to focus on the newly introduced proteins during testing. The large exchange of genetic material resulting from traditional breeding practices makes allergenicity testing of new traditionally produced varieties impractical.

Researchers also are using antisense technology to remove allergenic proteins from food, such as rice and soybeans, and similar approaches could be used for allergenic foods such as peanuts. Researchers also are at work on reducing the risk to people with food intolerances from such common foods as wheat, rye and barley. Continued research and product development in this area will expand the choice of foods available to those who suffer from food-related allergies.

For information on the potential allergenicity of StarLink^TM corn, click here.

Resources:
General Information on Food Allergies:

• Food and Drug Administration, Center for Food Safety and Applied Nutrition, Information about Food Allergens.
• International Food Information Council, IFIC Review: Understanding Food Allergy (2001).
• National Institutes of Health, National Institute of Allergy and Infectious Diseases.
  Provides information on the latest research into allergies.
• S.L. Taylor and S.L. Hefle, Food Allergies and Other Food Sensitivities, Institute of Food Technologists Scientific Status Summary (2001).

• Maryanski, J. 1997. Bioengineered foods: Will they cause allergic reactions? Food Allergy News vol.7 no. 1.
• "Statement on Policy: Foods Derived from New Plant Varieties; Notice," Federal Register May 29, 1992, 57(104): 22984-23001.

Environmental Protection Agency:

• Bt Plant-Pesticides Biopesticides Registration Action Document, II Science Assessment, B. Human Health Assessment (October 15, 2001).
  The EPA concludes that Bt proteins pose little risk of allergic reactions.

Related Link:

• National Research Council, Genetically Modified Pest-Protected Plants: Science and Regulation (2000).

• 2nd Joint Food and Agriculture Organization/World Health Organization Consultation on Foods Derived from Biotechnology, Allergenicity of Genetically Modified Foods, January 22-25, 2001, Rome, Italy.
• International Life Sciences Institute, The Safety Assessment of Novel Foods, Guidelines, ILSI Europe Novel Food Task Force (1995).
• Taylor, S.L., and Hefle, S.L. 2001. Assessing the allergenicity of foods produced through agricultural biotechnology: A new decision tree approach. Food Allergy Intolerance 2: 149-156.
• Organization for Economic Cooperation and Development, Safety Assessment of New Foods: Results of an OECD Survey of Serum Banks for AllergenicityTtesting, and Use of Databases (1997).
  Available in English and French.
• Metcalfe, D.D., et al. 1996. Assessment of the allergenic potential of food derived from genetically engineered crop plants. Crit. Rev. Food Sci. Nutr. 36: S165-S186.

• Buchanan, B.B. 2001. Genetic engineering and the allergy issue. Plant Physiology 126: 5-7.
• FAO/WHO Expert Consultation on Foods Derived from Biotechnology, Biotechnology and Food Safety, Working Papers.
  Papers covering allergenicity and other food safety issues.
• Hodgson, E. 2001. Genetically modified plants and human health risks: Can additional research reduce uncertainties and increase public confidence? Toxicological Sciences 63: 153-156.
• Institute of Food Technologists, "Human Food Safety," Expert Report on Biotechnology and Food (2000).
  Food safety chapter, a one-page chapter summary and an IFT backgrounder on food safety available.
• Nordlee, J.A., et al. 1996. Identification of a Brazil-nut allergen in transgenic soybeans. New England Journal of Medicine 334: 668-693.
• Samuel B. Lehrer, "Potential Health Risks of Genetically Modified Organisms: How Can Allergens be Assessed and Minimized?" Agricultural Biotechnology and the Poor, Consultative Group on International Agricultural Research (1999).
• National Food Processors Association.
  A good source of information about food allergies, including an "Industry Code of Practice" to manage food allergens.
• Pew Initiative on Food and Biotechnology, A Snapshot of Federal Research on Food Allergy: Implications for Genetically Modified Food (June 2002).

• Matsuda, T., Alvarez, A.M., Tada, Y., Adachi, T., and Nakamura, R. 1993. Gene engineering for hypo-allergenic rice: Repression of allergenic protein synthesis in seeds of transgenic rice plants by antisense RNA. Proceedings of the International Workshop on Life Science in Production and Food-consumption of Agricultural Products, Tsukuba, Japan.
• Food and Agriculture Organization/World Health Organization Expert Consultation on Foods Derived from Biotechnology, Biotechnology and Food Safety, Working Papers, Topic 10: Potential of Foods from which Unfavourable Components have been Removed (2000).
• U.S. Department of Agriculture, Agricultural Research, "Researchers Develop First Hypoallergenic Soybean," (September 2002).

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