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incomplete. Therefore, we cannot examine the sequence of a nucleic acid molecule and predict its regulatory function in a given organism. Inserting DNA sequences that possess unanticipated regulatory activities into the genome of a food-producing organism could disrupt any of the cellular processes in which DNA or RNA par- ticipate, including replication, transcription, translation, recombi- nation and transposition. Disruption of transcription or translation could alter the level of expression or the timing of the expression of any protein that is normally expressed in a food-producing organism. This could alter the allergenicity or toxicity of the food derived from that organism, as described below, and could also alter its nutritional or other characteristics. Disruption or alteration of replication, recombination or trans- position mechanisms could, among other things, alter the plastici- ty or stability of the recipient organism's genome, leading to increased rates of mutagenesis and consequently to a range of problems, as described below. In addition to allergenicity, recombinant proteins could mani- fest a variety of other biological activities, and, in the case of recombinant enzymes, could catalyse the production of other compounds with biological activities not normally present in a particular food. For instance, such substances could act as toxins, irritants, hormone mimetics, etc., and could act at the biochemi- cal, cellular, tissue or organ levels to disrupt a range of physiolog- ical functions. An example of a class of genetically engineered foods of partic- ular concern are those that have been modified to produce biologi- cal control agents, such as the family of insecticidal Bt enterotox- ins. Each of the Bt toxins is specific for a certain class of insects. The Btk toxin, which has been used topically in organic farming for many years, has not been reported to cause toxic reactions in consumers when used in this way. However, it would not be sur- prising if a compound such as Btk toxin, which has powerful bio- logical activity in one class of organisms, might also have some biological activity even in a distant phylum such as the verte- brates. Such activity might become apparent if the toxin is con- sumed in larger amounts, as will occur in transgenic foods derived from organisms engineered to express this toxin constitutively at high levels. Narmoller Ate ln, De WINRAR Ne Ane ane ee teen meaty Met rr ate ee tee Cate wate Bee eee ee ALLERGENS GENERATED IN RECOMBINANT FOODS from organisms engineered to express this toxin constitutively at There exist several mechanisms by which allergens could be high levels. expressed in foods through genetic Normally when used topically, Bt engineering. A number of molecu- toxin is degraded to undetectable lev- lar mechanisms have also been iden- els by solar UV light and other mecha- tified through which the genetic . nisms in just a few days. However, manipulation of food-producing Because allergen-carrying Bt-engineered plants produce this organisms could generate new aller- transgenic foods will in most cases toxin continually, resulting in much gens or increase the allergenicity of . . . higher steady-state levels. proteins normally present in food- maintain the appearance of their Furthermore, the toxin will be present producing organisms. natural non-allergenic not only on the surface of the plant but Because allergen-carrying trans- u internally where, protected from UV genic foods will in most cases main- counterparts, they pose a serious light degradation, it may accumulate. tain the appearance of their natural, The result is that consumers of these non-allergenic counterparts, they hazard to the consumer. foods may take in much larger pose a Serious hazard to the con- amounts of Bt toxin than is the case sumer. Consumers will not be able with foods derived from topically- to avoid these allergenic foods treated plants. Consequently, the because they will not be able to distinguish them from the corre- excellent safety record of topically-applied Bt toxin does not con- sponding natural foods. The labelling of all genetically engi- stitute reliable evidence indicating that foods derived from plants neered foods could, of course, solve this problem and would also genetically engineered to produce Bt toxin will be safe. oo make it possible for health authorities to trace allergen problems that arise. About the Author: At present, empirical evidence regarding the generation of aller- Dr John Fagan has spent more than 24 years using cutting-edge mole- eg . 5 Og : cular genetic techniques in cancer research. He earned a B.Sc. (cum genic foods through genetic engineering Is sparse, since few of laude with distinction in chemistry) from the University of Washington the genetically engineered foods now under development have and a Ph.D. in biochemistry and molecular biology from Cornell been thoroughly tested for allergenicity. However, one example —_ University. He has authored more than 50 technical articles, which has already come to light. have been published in international, peer-reviewed journals including Pioneer Hybrid has developed soybeans with a nutritionally Biochemistry and Molecular and Cellular Biology. A biochemistry pro- balanced amino acid composition. They accomplished this by _ fessor at Maharishi University, he recently published Genetic engineering into these beans the gene for a brazil nut storage pro- Engineering: The Hazards; Vedic Engineering: The Solutions. tein. However, this protein turns out to be allergenic to a signifi- In recent years Dr Fagan has been increasingly concerned about the cant proportion of the population. Pioneer Hybrid has wisel dangers of genetically engineered foods, the hazards of releasing geneti- . P : pop’ . ny y cally engineered organisms into the environment, and the risks of germ- decided to terminate plans to commercialise this product. line genetic engineering in humans. In November 1994 he took an ethi- About the Author: Dr John Fagan has spent more than 24 years using cutting-edge mole- cular genetic techniques in cancer research. He earned a B.Sc. (cum laude with distinction in chemistry) from the University of Washington and a Ph.D. in biochemistry and molecular biology from Cornell University. He has authored more than 50 technical articles, which have been published in international, peer-reviewed journals including Biochemistry and Molecular and Cellular Biology. A biochemistry pro- fessor at Maharishi University, he recently published Genetic Engineering: The Hazards; Vedic Engineering: The Solutions. In recent years Dr Fagan has been increasingly concerned about the dangers of genetically engineered foods, the hazards of releasing geneti- cally engineered organisms into the environment, and the risks of germ- line genetic engineering in humans. In November 1994 he took an ethi- cal stand against these applications, urging scientists to take safer, more productive research directions and to focus more on prevention and less on high-tech therapeutics. He underscored these warnings by returning a US$613,882 grant to the National Institutes of Health and withdrawing grant applications worth another US$1.25 million. Currently, Dr Fagan is conducting a global campaign to alert the pub- lic to the hazards of genetically engineered foods. His goal is to reshape national and international policy and regulations regarding the safety, testing, labelling and importation of genetically engineered foods. TOXINS AND IRRITANTS GENERATED IN RECOMBINANT FOODS Most substances that will occur in foods as a result of genetic engineering will be proteins that will be present in only trace con- centrations. Nevertheless, those added components, in even trace amounts, may substantially alter either the nutritional or other bio- logical characteristics of the food. 20 - NEXUS FEBRUARY - MARCH 1997