Peggy G. Lemaux, Ph.D.
Department of Plant and Microbial Biology
University of California, Berkeley CA 94720
In order to understand and appreciate the differences that this new technology brings to agricultural crops and to understand what scientific risks are involved in using and consuming these varieties, it is important to have a cursory understanding of how the methods by which crop 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.
In our analogy the crossing of the two species is comparable to combining the information in the two different stacks of books randomly. The resulting variety was then backcrossed over many years to the commercial variety, resulting in more and more of the "text" of the final book being from the commercial variety. By doing this, a higher sugar tomato was achieved. In this example, the final stack of books had mostly volumes from the domesticated species; the information from the wild species was restricted to only about 100-200 pages. In those pages was the information for higher sugar content and other information that they hadn't "read". Part of the extra 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 information retained from the wild species.
In the second approach the goal was the same, to increase the sugar content of the commercial tomato. This time they did it by looking at the "recipe" for the tomato fruit and figuring out what made it sweet. They were able to identify a single gene responsible for the sweetness; it prevented the breakdown of sugar. By manipulating that single gene, they made a sweeter tomato by turning off the machinery that makes the sugar-degrading enzyme. That single gene in the analogy is equivalent to a half page of information.
In the second case where "genetic engineering" methods were used, the researchers could "read" the information in the half-page and predict more precisely the outcome of adding the half-page of information to the tomato because it involved more defined and smaller amounts of genetic material. Although not obvious from this example another difference with genetic engineering is that the source of the half page of information can be any living organism; the donor and recipient organisms need not be related as is necessary with classical breeding.
Another area of interest, so-called "functional foods" or nutraceuticals, is likely the area of greatest activity in the private sector in the future. What does this mean? This is the engineering of an edible plant part to deliver an extra benefit to the consumer. This can be accomplished in one of two ways. First through the removal of an antinutritional, e.g., making foods like rice and wheat less allergenic or removing toxic compounds, like the glycoalkaloids from potatoes and cassava. A second way to create a functional food would be through the addition of a component that renders a food more nutritious, e.g., by raising the level of certain vitamins, amino acids or minerals in the food. Examples of this approach include increasing the beta-carotene or iron content of rice or the antioxidant content of broccoli. Another goal of functional foods is to use foods as a delivery vehicle for medicinals. Examples of this use are foods that when consumed vaccinate humans and animals against disease. Foods can also be used as a vehicle to develop immunotolerance, which can help prevent diseases like Type II juvenile diabetes.
Plants can also be used to make other products currently being made with non-renewable resources, items like industrial oils, gasoline substitutes and biodegradable plastics. Plants are our ultimate renewable resource and can be grown year after year to provide these in-demand products.
The preceding paragraph describes the spectrum of types of engineered varieties that can be made, but only a small fraction of them are grown commercially. The commercial varieties involve only a limited number of crop species and focus on a few agronomic and pest-resistance traits. Despite this fact, acreage being planted in engineered cotton, soybean, corn and potato varieties is substantial and has been rising over the last three years. In the summer of 1998, 26.5% of the corn planted in the U.S. was genetically engineered; 27% of the soybeans; 44% of the cotton and 3% of potatoes. Acreage continued to rise to approximately 75 million acres during the 1999 growing season and was anticipated to continue rising during the 2000 planting season.
But how are these first varieties performed for farmers in the field? Some farmers have been pleased with the new varieties; others see a lot of room for improvement. As with the first products of many technologies, these offerings are crude in comparison to later generation versions that will likely be more efficient and efficacious and in a wider variety of genetic backgrounds. These new varieties have brought some new changes for farmers, like having to pay upfront for the high-cost seeds before knowing whether the investment would pay off because of high pest or weed pressure. They also have realized that, as with hybrid crops, they are not able to re-plant from saved seeds, although most high-yield farmers do not engage in this practice.
In July of 1999 a report was released by the National Center for Food and Agricultural Policy that attempted to quantify the effects of the new B.t. crops. These are varieties that have been engineered with their own pesticidal compound, a naturally occurring protein made by a soil bacterium known as Bacillus thuringiensis. With some of the engineered varieties, like Bollgard cotton, profits for farmers were realized. Adjusted figures showed an overall reduction of 5.3 million less pesticide treatments, resulting in an overall net benefit to cotton producers of $92 million.
In other crops, like B.t. corn, profits for farmers varied from year to year. Infestation pressure was heavy in 1997, leading to savings for farmers of $72 million; in 1998 when infestations were low, farmers lost $28 million! This resulted from the fact that farmers had to decide whether to pay the increased costs for the engineered varieties before knowing the severity of the infestation. ?For herbicide-tolerant (HT) varieties, the conclusions were also mixed. A report from Iowa State University showed that in 1998 Iowa soybean farmers using Roundup Ready seed saved roughly 30% on their herbicide costs. This was impressive but the savings realized in chemical inputs was offset by a yield drag in the engineered varieties that caused a loss of 2 bushels per acre, meaning that total costs per acre for GM (i.e., genetically modified) and non-GM soybean were about the same. Recently Charles Benbrook, an independent biotechnology consultant, published a review on Roundup Ready soybean based on over 8200 university soybean varietal trials performed in eight Midwestern states. His report concluded that in 1998 the yield drag of Roundup Ready soybean, compared to all other varieties tested, averaged between 5 and 10 percent lower, again wiping out the savings realized by the lower inputs. Why the yield drag? Likely it is due to the fact that the Roundup Ready trait was only put into a limited number of soybean varieties, which were not optimally suited for growing in all areas. Putting the trait into a larger number of varieties optimized for growth in diverse areas should improve the savings realized by the farmers. Despite the lack of dramatic financial savings, Benbrook claims that the varieties are popular with farmers because of simplified and more diversified weed management options.
Analysis of the use of HT canola showed similar patterns. Although these varieties offer a large weed-control advantage, this did not necessarily translate into yield advantages as large as farmers had hoped for. A big factor in how advantageous these varieties were depended on whether or not weeds were present that were hard-to-control with conventional systems. If farmers had a big problem with difficult weeds, like stork's-bill or cleavers, then the herbicide-tolerant system was a huge advantage, with yield increases of 13 to 39 percent over conventionally controlled fields. But, if the most competitive weeds were not present, yields using conventional seed and weed-control systems were not that much lower. A clear advantage of HT crops is that more weed control options are available, which with proper management can lead to improved weed control strategies and more sustainable systems that include herbicide rotations.
Foods created by classical breeding methods and consumed in the U.S., Europe and Japan are perceived as safe for themselves and their families. There is a long history of safety, or acceptable risk, associated with these foods. This sense of safety exists, despite the fact that in their natural state many of our foods contain toxic compounds. Even one of the staples of the American diet, the potato, contains compounds that can make consumers sick. But years of selection by breeders have lowered the levels of these natural toxins in the potato and other species and very few cases of acute disease caused by such compounds occur. But, as with nearly every activity in which humans engage, food consumption is not zero risk, but is perceived as acceptable risk.
Genetic engineering or biotechnology is a new technology used to modify foods. In the U.S., consumer surveys over the last ten years have found the majority of consumers willing to eat the products of the technology. This trend was seen in surveys in the U.S. by the International Food Information Council (EFFACE) as recently as February and October of 1999. 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 fell in the most recent survey, the vast majority of consumers are still willing to eat these foods.
The EFFACE poll and another recently conducted poll, a Gallup poll conducted on September 23-26, 1999, however, do show some significant shifts from earlier polls. 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, 20% were unsure, but a significant fraction, 27%, thought it did pose a serious health 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 and assuring that they are safe. In the October EFFACE poll, 76% of Americans had a lot or fair amount of confidence in the federal government to assure food safety; in the Gallup poll, 76% expressed confidence.
The reasons for this difference in attitude are very complex. A major contributing factor is that there were several food safety scares that made E.U. consumers fear that their regulatory system could not assure food safety. These included 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 an easier platform for activists' claims of demonstrable risks with GM food.
In addition, there is an element of involuntariness to the consumption of GM foods. The engineered varieties were large-acreage crop varieties, like corn, cotton and soybean, the processed forms of which are found in most processed foods. Because of this, large numbers of products streamed into the marketplace, containing GM corn starch and soy flour and soy, corn and cottonseed oil made from G.M. varieties. Consumers felt that they had not been consulted on this aspect of food production and in many cases were led to believe that they were "guinea pigs" in a large corporate "food experiment".
There are some additional, more fundamental differences and issues that vary between Europe and the U.S. that have played a role in the differing attitudes.
The role of science and technology. In the U.S., Canada and Japan it is generally accepted that science and technology play a role in improving people's lives. Many European citizens are wary of technological change and are not convinced of its potential long-term, positive consequences.Physical Separation from GM crops. Agricultural land in the U.S. is plentiful and urban dwellers are far away from the land on which GM crops are grown. In Europe, open space is rare and individuals find themselves located squarely next to fields of GM corps, causing them to be much more prone to concerns that these plants might have a negative impact on the environment.Economic Issues. Food imports and farm subsidies in the E.U. are high, creating a strong economic incentive to ban U.S. food imports. Obviously a trade embargo results in a favorable economic cash flow situation for the E.U.Public Education Efforts. In the early 1990's, members of U.S. public and private research organizations, including universities and trusted governmental and professional agencies, began pro-active efforts to educate the public about genetic engineering, helping to avoid the existence of an informational void, which could be filled by other organizations.Role of Multinational Corporations. Lastly, a new paradigm for agriculture arose, resulting in part from the increased costs of product development with the new biotechnological methods. This led to the situation where the development, deployment and production of the new foods were largely controlled by a handful of multinational companies. This type of control, unparalleled in the history of agricultural production, is unsettling to both those involved in food production and those who consume the foods.
Tensions and unrest reached a feverish peak in Europe in late 1999. Anti-biotechnology efforts then crossed the Atlantic to Canada and the U.S. A very significant early event in the U.S. was getting baby-food giant, Gerber, to agree not to use GM ingredients in their baby food. Not only did they agree to that, but they also agreed to use "organically grown" ingredients to the extent possible. After this pronouncement several other large companies followed suit.
Perhaps the most significant was Archer Daniels Midland, one of the country's largest grain handlers. In late summer of this year, ADM demanded that their suppliers segregate GM from non-GM grain, because, as they said, of "a changeºin consumer demand". International trade had become a question. What products would and would not be accepted in Europe? Would they have to be guaranteed to be GM-free? Soon food processors paid premiums for GM-free grain. According to a Kiplinger article of January 6, ADM and Con Agra paid a premium of as much as 50 cents a bushel for non-GM grains - about 10% above the average price for soy and 25% above the average for corn.
But Cargill, another large processor, bucked the trend. They told producers that this season and next they will accept GM crops at all U.S. grain-handling, oilseed processing and wet corn milling facilities, even varieties approved in the U.S. but not yet approved in Europe. And Kellogg, despite an advertising campaign focusing on "Frankenflakes", is standing firm in the U.S. in using GM ingredients in their cereals, although they have removed them from products destined for Europe. They believe products made from GM crops are safe and that the majority of consumers are not demanding their removal.
Perhaps in part because of such newspaper headlines and the uproar in Europe, interest in labeling in the U.S. rose. This was reflected in the Gallup poll, where numbers supporting labeling climbed to over 2/3 of respondents, even if it meant an increase in price. This increased interest led the FDA to convene a series of town hall meetings around the U.S. to seek consumer input on their labeling policies.
What are the issues with labeling? First of all, for many it is likely not 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 out of a right to know. Others want to use the label to identify GM foods so they can use their "economic clout" to vote against the technology.
Is the unrest over GM foods and interest in labeling just a hiccup that will go away after a short time? Not likely. There are many differences in the situation from that of a year ago. Now the issues go beyond the actual safety of such foods. It has to do with increasing public awareness and fear of the unknown, with international trade issues and with the larger sphere of organizations involved in the effort to question GM foods and with the public's attitudes toward agriculture and risk. We live in a technologically complex world and it is often difficult for people to understand the nuances of complicated technologies. In such a situation, it is much more common to fear the consequences of the technology in the short term than to feel comfortable with its safety. In addition, when direct personal benefit is not seen, consumers will not want to take a risk, no matter how small. Benefits of GM crops so far have not been directed to the consumer; benefits to farmers, even if they are said to help the environment, simply don't carry weight anymore since only 2.7% of the population is involved in farming.
How will it all play out?
How will the whole labeling and public acceptance scenario play out? It is difficult to make predictions for the short-term (2-5 years), but it is likely that in ten years the technology will pervade food production. Why? Many of the current products have not achieved the potential necessary for user or consumer acceptance. New information gained from studies of the genome will provide new avenues for crop improvement that cannot be achieved in any other way.
Strategies for creating the new foods will be improved and refined, just as the computer evolved from a machine that took up city blocks to one that fits on your wrist. In addition consumers will gain familiarity with the foods and have time to judge their safety and new generation GM crops will offer more tangible benefits to them.
In the end, some products of the technology will find favor with users and consumers; some will not. Some will be a commercial success; some will not. Some will be developed in the private sector; some in the public sector. But in the long-term, biotechnology is likely to find applications and result in products that will be important tools in the farmer's toolbox and that will be accepted and likely even sought after by consumers.