Talk presented at the California/Arizona Watermelon Association meeting in San Francisco, CA, on January 14, 2000
Peggy G. Lemaux, Ph.D.
Department of Plant and Microbial Biology
University of California
Berkeley CA 94720
Take a look at the marketplace. Consumers' awareness of the value of eating fruits and vegetables and, in fact, their consumption of fruits and vegetables has increased. The Five-A-Day program, initiated in 1991, aimed to increase public awareness of the value of eating five servings of fruits and vegetables a day and it worked! But is increasing market awareness the only factor that is going to drive fruit and vegetable sales upward? I would say no. Have you looked on the shelves of your favorite supermarket lately? Your local drug stores? With increasing frequency consumers are choosing food products that claim health benefits. Manufacturers of cereals and whole grain products claim improved health by eating their foods. Consumers have turned to calcium-fortified orange juice in large numbers to bolster calcium intake during both the formative years and during later years to alleviate symptoms of osteoporosis. Consuming wine has some positive health effects, perhaps in part because of compounds that serve as very strong antioxidants. If you listened to your mother about eating your broccoli, you would be well-served; this much maligned vegetable has naturally occurring products with anti-cancer properties.
Why this new interest in natural products? For years, folk remedies based on compounds found naturally in certain foods have been used by some to enhance their health and to treat their ills. Often these approaches were not accepted by the U.S. medical community. Recently, however, it has been possible to identify the compounds suspected of causing the beneficial, or sometimes detrimental, effects, which can then be tested to confirm their biomedical effects. This leads to a new era of foods, the health claims of which have been validated by the scientific community and more widely accepted by consumers.
What does this mean? People will likely be looking more and more to their foods to help them create a healthier lifestyle. And one of the cornerstones of this new, healthier diet will be fruits and vegetables, both as they exist today and as they will evolve through using genetics to change the attributes of foods. One of the technologies that can be used take advantage of this new knowledge to change fruits and vegetables is biotechnology. Just last Friday evening on NBC Nightly News with Jane Polley, she featured the work of my colleague and me on developing hypoallergenic foods and milk through the molecular manipulation of a basic molecule present in all living cells. Researchers have been talking about the "promise of biotechnology" for over a decade, but until recently there were no products in the marketplace. Today biotechnology is a reality. We have crops in the field that have been genetically engineered and we have products in the marketplace that are being eaten by consumers. Beginning in 1994, the first wave of fruits and vegetables resulting from biotechnological applications were introduced into pilot test markets in the U.S. Foods like longer shelf-life melons, viral resistant squash and virus resistant potatoes.
In order to appreciate the power of this new technology, it is important to have a cursory understanding of how the methods by which vegetable and fruit varieties have been traditionally developed differ from or are similar to the new genetic engineering techniques. This is easiest to explain using an analogy. The genetic information in a cell is the recipe that determines what cells will do; that recipe is written in chemical units. If we represent each chemical unit in the genome by an alphabetic letter, it would take 1700 books, each of 1000 pages, to hold all the information needed to "build" a wheat plant, for example. Stacked on top of one another, the books would be as high as a 20-story building! So when we do classical breeding, it is like mixing two stacks of books, but genetic rules state that we can only end up with one 20-story building. To demonstrate how these two technologies are different yet similar, I will use an example based on work done by Alan Bennett at UC Davis. His laboratory crossed a wild tomato with a commercial variety in order to transfer the higher sugar content of the wild species into the domesticated tomato. The idea was to transfer only the higher sugar characteristic to the domesticated tomato, leaving behind the small size, bitter taste and lower yield of the wild relative. By crossing the two tomato species and backcrossing to the commercial variety over many years, a higher sugar tomato was achieved. The end result was a sweeter tomato. It resulted from the fact that the two different stacks of books were combined and the information randomly mixed. The final stack of books had mostly volumes from the domesticated species, with about 100-200 pages from the wild species. In that 100 pages was the information for higher sugar content and other information that they hadn't "read".
Part of the additional information from the wild species turned out to cause reduced fertility in the resulting tomato plants. This is because with classical breeding, the breeder has only limited control over the final outcome. In the second approach the goal was the same, to increase the sugar content of the commercial tomato. This time they did this by looking at the "recipe" for the tomato fruit and, by doing so, they identified a single gene, one responsible for the breakdown of sugar. Through molecular technologies they engineered a sweeter tomato by turning off the machinery that makes the sugar-degrading enzyme. This is equivalent to a half page of information in our analogy. In the second case where "genetic engineering" methods were used, they knew everything about that new half-page of information they were adding; they had "read it". Therefore, the outcome of genetic engineering is often more predictable because it is more precise and involves the exchange of much less information. Although not obvious from this example another difference is that the source of the genetic material with genetic engineering is any living organism; the donor and recipient organisms need not be related.
Is the development of new varieties using genetic engineering a temporary market fluctuation or are these varieties likely to become major parts of the marketplace in the years to come? Mr. Alfonso Roma, the president of Empresas La Moderna SA, or ELM, the largest vegetable seed company in the world, believes that within ten years, 80% of all fruits and vegetables will be genetically engineered in one way or another. Further he envisions vegetables such as nonbrowning lettuce, broccoli with enhanced cancer-fighting properties, and produce of all kinds that won't wrinkle, spoil or blemish. Some products are already well along in the commercial pipeline, viral-resistant squash and longer lived tomatoes; others are only in early stages of development, sweeter peas and insect-resistant cucumbers. Other products, not directly requiring biotechnology but making use of indirect benefits of the development of genetic engineering, are currently being developed. These include a milder jalapeo pepper for salsa, a product that now competes with ketchup in dollar sales in the U.S., baby carrots, a hit in packed lunches and airline meals, and hamburger-sized pickle slices that fit perfectly in a bun!
Outside the walls of ELM, there is much activity in both the public and private sectors. Some of the activity is aimed at increasing resistance to pests, like this example of viral resistance in papaya or European Corn Borer resistance in maize. Molecular approaches are also being devised to provide tolerance for plants from stresses, such floods, cold and salt. These strategies are more complicated and will require longer to accomplish. Agronomic traits are also being targeted. By understanding the basis for fertilizer usage by plants it is hoped that one can engineer them to be more efficient at the process. Genes have also been identified from algae that appear to increase yield significantly. Herbicide tolerant crops, if deployed responsibly, can lead to lower inputs of pesticides and to lower soil erosion from low-till approaches to weed control. Another area of interest is under the broad term "functional foods" or nutraceuticals; this is likely the area of greatest activity in the private sector in the future.
What does this mean? This is the engineering of a edible plant part to deliver an extra benefit to the consumer. This can be accomplished in one of two ways. First the removal of an antinutritional or by the addition of a component that renders a food more nutritious by raising the level of certain vitamins, amino acids or minerals in the food. Examples of the latter include increasing the beta-carotene or iron content of rice or the antioxidant content of broccoli. Examples of the first approach would be making foods like rice and wheat less allergenic or removing toxic glycoalkaloids from foods like potatoes and cassava. Another goal of functional foods or nutraceuticals is to use foods as a delivery vehicle for medicinals. Examples of this use are the use of foods to vaccinate humans and animals against disease. Foods can also be used as a vehicle to develop immunotolerance, which can help prevent Type II juvenile diabetes, currently being tested in human and animal models. Plants can also be used to make other products currently being made with non-renewable resources, items like industrial oils, gasoline substitutes and in this example biodegradable plastics.
Plants are our ultimate renewable resource and can be grown year after year to provide these in-demand products.
Despite its promise, consumers are nervous about some of the products of the technology and by whom they are being developed. But, biotechnology is not the first technology over which intense public discussion has arisen and, if constructive, such discussions can help shape constructive deployment and use of the technology. Furors have arisen in the past, over the shift from margarine to butter, over pasteurization, microwave ovens, and food irradiation. The latter is a technology that held a great deal of promise for increased food safety and might have prevented the deaths associated with Jack in the Box hamburgers.
But fear was struck in consumers by activists, who claimed that there were unknown risks involved in the consumption of irradiated foods. Only recently have those fears been quelled and irradiation of poultry and beef been approved and implemented in the U.S. Consumers in the U.S., Europe and Japan take for granted that the foods created by classical breeding methods are safe for themselves and their families. This despite the fact that in their natural state many plants contain toxic compounds. Even the potato, a very close relative of the tomato, contains compounds that can make human consumers sick. But years of selection for less poisonous varieties have lowered the levels of toxins in the potato and other crop species. Despite the presence of these natural toxins, there are very few cases of acute disease caused by food. But, as with nearly every activity in which we engage, food consumption is not zero risk. It is important to differentiate between safety and zero risk.
What individuals define as "safe" is, for them, "acceptable risk" and cannot be determined scientifically. Genetic engineering or biotechnology is a new technology used to modify foods. In the U.S., consumer surveys over the last ten years, and up until the last few months, have found the majority of consumers are supportive of biotechnology. This trend toward acceptance was seen in recently conducted surveys in the U.S. by the International Food Information Council (IFIC) in February and again in September of this year. U.S. consumers were asked if they would be willing to "purchase a food modified by biotechnology to taste better or fresher" (62%, Feb; 51%, Oct.) or a food "modified by biotechnology to be protected from insect damage and requiring fewer pesticides" (77%, Feb; 67%, Oct.). Although the numbers have fallen somewhat in recent months, still the vast majority of consumers are willing to eat these foods. The more recent publicly released polls, a Gallup poll conducted on September 23-26, 1999 and the IFIC poll taken in late October, do show some significant shifts from earlier polls, however.
Respondents in the Gallup poll were asked to rate the likelihood that biotechnology poses a serious health hazard to consumers; 53% thought it did not present a serious hazard, 20% were unsure, and what I thought to be a significant fraction, 27%, thought it posed a serious hazard. This result seems to be at odds with the expressed confidence that the respondents have in the U.S. Food and Drug Administration, the regulatory arm that is responsible for monitoring genetically engineered food products. In the September 1999 IFIC poll, 76% of Americans polled had a lot or a fair amount of confidence in the federal government to assure safety in our food supply. In the Gallup poll, a similar result was obtained; 76% of Americans had a great deal or fair amount of confidence in the federal government to ensure food safety.
The situation is quite different in the European Union. There had been several recent food safety scares, such as the mad cow disease crisis in the U.K. and the dioxin scare in Belgium. The pronouncements and decisions made by government officials during these controversies were perceived by many to be based on political expediency rather than on public safety concerns. This undermined consumers confidence in the government to assure food safety with biotech foods and led to more willingness to listen to activists' claims. Labeling Interest in labeling, as evidenced in the Gallup poll, has risen dramatically over previously conducted polls with over 2/3 of respondents in favor of labeling, even in light of a possible increase in price. This difference from earlier polls is interesting because it is in apparent contrast to expressed faith in FDA regulations. This is an added indication that the labeling issue is not a food safety issue, rather a consumer choice issue. U.S. consumers are interested in labeling of GM foods, but recent polls indicate that they also favor labeling to indicate what pesticides are used on the plants and the country of origin of the foods.
A federal bill was introduced, supported by 48 Senators and Representatives that demands labeling of GM foods; a bill is also being introduced into the California legislation, as well as a drive to get an initiative on the ballot related to labeling in CA. Perhaps in light of this activity and in issues related to international trade, the FDA recently conducted public hearings to listen to consumers' concerns and what role the FDA should play in the labeling of these foods. I attended these rather contentious hearings where pro and con sentiments were heard.
First of all, I don't think for many it is a food safety issue, rather it is a personal choice issue. Some consumers just want to know that they are eating something that has been genetically engineered, simply out of a right to know. Others want to use the label to identify GMOs so they can use their "economic clout" to vote against the technology. Conclusion How will the whole labeling and public acceptance scenario play out? I recently participated in a panel for a T.V. series on biotechnology. With me on the panel were a former president of the Sierra Club, one of the organizations openly opposed to genetic engineering, and a former FDA administrator, who now spends his time at an academic think tank. When asked by the commentator to make a prediction about where GM crops would be in three years, we all looked at each other and shrugged our shoulders. Despite this inability to predict in the short-term, we were all confident that in ten years the technology would pervade agriculture and lead to advances that will deliver consumer benefits and improvements in the environment. It is likely that some products and some applications of the technology will not survive in the marketplace. In other instances products will be delivered to the consumer where the human health and environmental benefits will be easily seen and appreciated.
© 1999 Peggy G. Lemaux