The field of biotechnology reached a milestone when the Flavr Savr tomato became the first genetically engineered food product available to U.S. consumers.
In May, 1994, Calgene, Incorporated,
In 1991, chief executive officer of Calgene Roger Salquist examines genetically modified tomatoes that are able to ripen on the vine before shipping instead of having to be picked green.
The Flavr Savr differed from other tomatoes in that it had been genetically engineered to ripen more slowly. This gave it a significant advantage because the tomato could remain on the vine until it had begun to ripen yet be marketed before it deteriorated. Although picked before fully ripe, it reddened naturally, without exposure to ethylene gas, and developed vine-ripened flavor and texture.
In the Flavr Savr, the production of polygalacturonase (PG), an enzyme that causes the pectin in tomato cell walls to break down, had been inhibited through genetic engineering. Scientists had identified the tomato gene responsible for producing PG and had used antisense ribonucleic acid (RNA) technology, discovered in cancer research, to suppress the gene’s expression.
Genetic engineering, also known as recombinant DNA (deoxyribonucleic acid) technology, enables scientists to target the specific gene responsible for a plant characteristic and suppress it or supplement it with a gene from a species with which that plant would traditionally be unable to breed. Genes from animals, bacteria, or other unrelated plant species can thus be inserted into plants.
Genes code for the production of enzymes, proteins that cause cellular reactions, through an intermediary called messenger ribonucleic acid (mRNA). Protein factories called ribosomes attach themselves to the mRNA and read it in order to assemble amino acids into enzymes. To produce the Flavr Savr, researchers determined the sequence of nucleic acids in the mRNA for PG, then reversed and inserted into the plant cells of the Flavr Savr’s parent. This reversed sequence adhered to the mRNA for PG and prevented ribosomes from manufacturing it.
The gene for reversed, or antisense, mRNA was inserted into the tomato’s DNA through plasmids
The Flavr Savr was controversial because it contained a marker gene from a bacterium that made it resistant to the antibiotics kanamycin and neomycin. Some people feared that eating antibiotic-resistant tomatoes would make them resistant to these antibiotics during illness. Others feared allergic reactions to the protein generated by the marker gene.
Calgene, a biotechnology agribusiness founded in Davis, California, in 1980, saw the potential for substantial profit from the vine-ripened tomato market and began developing the Flavr Savr in 1982. From 1987 to 1992, Calgene conducted premarket testing on the Flavr Savr. To reassure consumers, who were becoming increasingly uneasy about genetically engineered foods, Calgene asked the FDA to examine its test results and rule on the safety of the tomato variety. Agricultural plant products, whether produced by genetic engineering or traditional plant breeding, are regulated by the FDA under the guidelines of the Federal Food, Drug, and Cosmetic Act of 1938
In May, 1992, under increasing pressure to clarify its position on the regulation of genetically engineered foods, David A. Kessler, commissioner of food and drugs for the FDA, released a document titled Statement of Policy: Foods Derived from New Plant Varieties. In the report, Kessler stated that because the FDA was not aware of any data demonstrating that foods created through genetic engineering present any greater safety concern than traditionally developed foods, the FDA would regulate all food products on the basis of their individual characteristics, not their mode of origin. Furthermore, the producer is legally responsible for ensuring that a food product is safe. The FDA would require premarket testing and labeling of new foods only if they contained lowered concentrations of the important nutrients for which the food was widely consumed, if they had toxicant concentrations above an acceptable range, or if unexpected allergens were present.
The FDA’s refusal to regulate or label genetically engineered foods evoked a storm of protest from organizations such as the Environmental Defense Fund
In November, 1990, Calgene requested that the FDA issue an advisory opinion on the use of the marker gene in tomatoes. The FDA ruled it safe. In October, 1991, Calgene requested that the FDA issue a separate advisory opinion on the status of the Flavr Savr tomato as a whole food subject to the same regulation as other tomato varieties. Calgene also made the results of its premarket testing available to the FDA and to the public through the dockets branch of the FDA.
Disturbed by the public outcry following the May, 1992, FDA statement regarding its regulatory policy for genetically engineered foods, and realizing that successful marketing of the Flavr Savr depended on public acceptance, Calgene filed a food additive petition for the selectable marker gene with the FDA on January 4, 1993. This is the most stringent safety test that the FDA applies to a food.
In April, 1994, Calgene published the FDA’s review of Calgene’s data on the Flavr Savr, which concluded that the tomato had not been significantly altered, that the marker gene could not transfer antibiotic resistance to other organisms, and that the marker did not possess any of the characteristics of allergenic proteins. Also in April, the FDA’s Food Advisory Committee undertook a discussion of the safety review of foods produced by new biotechnologies, with the Flavr Savr serving as the discussion’s focus. The FDA issued a food additive regulation on the marker gene in May, 1994.
The Flavr Savr was marketed at the end of May, 1994, in the Midwest and in California. Calgene voluntarily labeled the tomato and provided in-store displays explaining its origin. It was reported to have sold out where offered.
The Flavr Savr tomato was the test case for the industry; its successful transit through the regulatory process and subsequent marketing ushered in an era of genetically engineered agricultural products. Marketing of these products was expected to result in enormous profits and growth, over time, for the agribiotech industry. Public pressure on the FDA to increase its regulatory oversight of genetically engineered food products continued, as did the debate between producers of genetically engineered foods and those who feared adverse environmental effects.
By 1994, more than thirty genetically engineered agricultural products had been developed and field-tested and were waiting to be marketed; numerous others were in various stages of development. Products expected to move into the market during the 1990’s included crops resistant to specific herbicides, viruses, fungi, drought, frost, salinity, and insects. Also in development were crops with superior food-processing traits such as longer ripening time or higher starch content, grains with the full complement of amino acids required by humans and domestic animals, healthier vegetable oils, and biodegradable plant substitutes for petroleum products such as motor oil.
Surveys indicated that although 70 percent of the American public was not opposed to genetically engineered foods, people favored labeling of these products as well as review of them by the FDA. The presidential administrations of Ronald Reagan
Bill Clinton’s
Environmental organizations, organic farmers, and scientists outside the biotech industry continued to express various concerns over the ecological effects of genetically engineered plants and urged extreme caution in introducing new plant species. They acknowledged that genetic engineering could be an extremely beneficial technology but pointed to the harm done by other new technologies, such as atomic energy and the insecticide dichloro-diphenyl-trichloroethane (DDT), which were implemented before their full effects were known.
In general, concerns centered on the fact that all elements of the environment exist in sensitive balance with one another. This balance is disrupted and existing elements evolve or are eliminated when a new element is introduced. There is no way to predict all the effects of introducing a new gene into a plant species or of introducing that plant into the environment. Laboratory tests are inconclusive in revealing all possible effects of genetic engineering because the environment cannot be simulated in a laboratory, and field testing poses the danger of releasing organisms into the environment that may affect it negatively and irreversibly.
The agribiotech industry claimed that the new plant species were the basis for a new, more ecologically sound agriculture. Many opponents, however, viewed genetically engineered plants as a temporary solution to serious, long-term environmental mismanagement or as a potential source of continued misuse. Environmentalists were alarmed by the industry’s concentration on the development of crops engineered to tolerate herbicides.
Insect-resistant crops engineered to contain a gene-producing toxin isolated from Bacillus thuringiensis (Bt), an environmentally safe pesticide,
Gene transfer of engineered characteristics from crops to related weeds was also an issue. The transfer to weeds of resistance to drought, salinity, frost, bacteria, fungi, viruses, herbicides, and pesticides would make them more competitive with both crops and noncrop plants in the environment. Hardier weeds would be more difficult to manage, perhaps requiring stronger herbicides than those currently in use, and might outcompete other species of noncrop plants, diminishing species diversity.
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Avise, John C. The Hope, Hype, and Reality of Genetic Engineering: Remarkable Stories from Agriculture, Industry, Medicine, and the Environment. New York: Oxford University Press, 2004. Examines the potential of genetic engineering and provides examples of achievements and failures in the field. Includes discussion of the Flavr Savr tomato. -
Ellstrand, Norman C., and Carol A. Hoffman. “Hybridization as an Avenue of Escape for Engineered Genes.” BioScience 40 (June, 1990): 438-442. Presents clear discussion of the threat to plant species diversity and weed control proposed by natural crossbreeding between weeds and related domestic crops genetically engineered to withstand drought, frost, salinity, insects, and herbicides. -
Gasser, Charles S., and Robert T. Fraley. “Genetically Engineering Plants for Crop Improvement.” Science 244 (June 16, 1989): 1293-1296. Discusses issues from the biotechnology industry’s standpoint, such as the need for patent protection to offset the cost of developing crops. Authors are employed by Monsanto, a leading agrichemical company. -
Hindmarsh, Richard. “The Flawed ’Sustainable’ Promise of Genetic Engineering.” Ecologist 21 (September/October, 1991): 196-205. Presents an articulate, well-supported environmental argument against genetically engineered plants and biopesticides. Discusses the threat to organic farming and the hidden agenda behind the restructuring of the agrichemical industry. -
Hubbard, Ruth, and Elijah Wald. “Genes for Sale.” In Exploding the Gene Myth: How Genetic Information Is Produced and Manipulated by Scientists, Physicians, Employers, Insurance Companies, Educators, and Law Enforcers. Boston: Beacon Press, 1993. Examines the dangers posed by conflicts of interest resulting from the pervasive links between the biotechnology industry and university faculty members and administrators, who often hold patents on biotechnological developments or act as paid consultants to the industry yet testify as government experts on the safety of products and regulatory processes. -
Kessler, David A. “Statement of Policy: Foods Derived from New Plant Varieties.” Federal Register (May 29, 1992): 22964-23005. Provides an excellent, readable overview of the FDA’s regulatory policy for genetically engineered foods. -
Lee, Thomas F. “Field of Genes.” In Gene Future: The Promise and Perils of the New Biology. New York: Plenum Press, 1993. Comprehensive discussion of the pros and cons of genetically engineered agricultural products. Presents the positions of the biotechnology industry, government regulatory agencies, and environmental groups with objectivity and balance. -
McKelvey, Maureen. Evolutionary Innovations: The Business of Biotechnology. New York: Oxford University Press, 1996. Examines the commercial development of biotechnology. Features figures, bibliographic references, and index. -
Suzuki, David, and Peter Knudtson. Genethics: The Clash Between the New Genetics and Human Values. Rev. ed. Cambridge, Mass.: Harvard University Press, 1990. Addresses the ethical issues that arise from the possibilities presented by DNA technology. Includes discussion of the importance of genetic diversity, recombinant DNA technology, and the use of plasmid for transferring genes from one species to another.
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