Hazards

(Excerpt from: Assessing the safety and nutritional quality of genetically engineered foods by John Fagan)

The hazards that may be introduced into foods through genetic engineering are three, (1) allergens, (2) toxins, and (3) reduced nutritional quality. This paper begins with a discussion of how genetic engineering may introduce these risks into foods, and then outlines the procedures for assessing whether or not a given genetically engineered food contains such hazards. In this discussion, foods, food ingredients, and food additives produced through recombinant DNA technologies will be called "genetically engineered," "recombinant," or "transgenic" foods, and the term food will be used to refer collectively to foods, food ingredients, food additives, and nutritional supplements.

Three sources of risk

The genetic engineering of foods involves the introduction of new genetic information into a food-producing organism. Some of the health risks associated with genetically engineered foods can be anticipated on the basis of what we already know about the characteristics of the food-producing organism in its unmodified state (called the unmodified organism UMO), from which the genetically engineered organism (GEO) is to be generated.

Other aspects of the risks associated with genetically engineered foods can be deduced from the characteristics of the organism that is the source of the genetic information introduced into the food-producing organism (called the gene source or GS). For instance, if a gene derived from peanuts is introduced into a tomato, food produced from the resulting genetically engineered tomato might cause allergic reactions in people that are allergic either to tomatoes (the unmodified organism) or to peanuts (the gene source).

In addition to risks that can be foreseen by considering the characteristics of the UMO and gene source, there is another source of potential risks. This is the procedure of genetic engineering itself. Current recombinant DNA methods and those likely to be developed in the future are all capable of accidentally introducing unintended changes in the function and structure of the food producing organism. As a result, the genetically engineered food may have characteristics that were not intended by the genetic engineer, and that cannot be foreseen on the basis of the known characteristics of the unmodified organism or gene source. The mechanisms by which gene modifications can lead to such changes are discussed briefly below and described in detail in Section C.