Scientists Leave The Lab To Defend
Bioengineered Food

Lila Guterman
April 14, 2000
Chronicle of Higher Education

The Demonstrators took to the streets of Oakland, Calif., in December, passing out leaflets and debating with anyone who would listen. They were nervous about genetically modified foods, and had timed their efforts to coincide with a public hearing on the topic, held by the Food and Drug Administration.

But their anxiety stemmed not from the health or environmental risks of bioengineered foods, nor from the trade or political issues surrounding the new technology. The demonstrators were scientists from the nearby University of California at Berkeley, joined by colleagues from u.c.Davis and Stanford University, who had turned out to express their support for agricultural biotechnology and to combat public fear of the crops.

The scientists wanted to offer an alternative view to that of environmental groups and others who have staged numerous protests in the United States against genetically modified foods in the past year. Recently, some of the protests have grown violent, with groups like the Earth Liberation Front destroying scientists' offices and genetically engineered crops at the Universities of California and Minnesota, and at Michigan State University.

Plant scientists in academe, the vast majority of whom support the use of techniques that transfer new genes into crop plants, have begun to respond to the publies outcry. Normally media-shy, they are trying to educate people about the science behind the techniques by engaging in debates, framing petitions, holding press conferences, writing newspaper articles, and addressing government agencies. They are urging the public to keep an open mind about the technology, and to heed the growing mass of data that pinpoint the risks and benefits.

The researchers see genetic engineering as a powerful tool to increase food production and protect the environment, and they worry that it could be lost if the public doesn't support it. They also worry that a loss of confidence in genetic engineering could cut off government and corporate support, forcing scientists to abandon their research. And they fear the long-term impact of scientific issues being decided based on incorrect information. "What should drive the issue is the science. Where there are legitimate scientific concerns, those clearly need to be addressed," says James N. Siedow, a professor of biology at Duke University. "The flip side of the coin is, we ought not to be basically throwing out the notion of commercialization of genetically mod ified organisms based on fear and half truths and outright falsehoods."

"We cannot approach biology as a riskfree enterprise, because it never is," says Susan R. McCouch, a plant scientist at Cornell University. Farmers and regulators should decide whether and how to apply various techniques with an understanding of how the benefits stack up against the risks. And, say many scientists, the potential that genetic engineering holds for improving crops and protecting the environment should figure large in that equation.

Changing A Cell's Dna

Techniques to insert foreign genes into plants were first developed in the 1970's. One method involves putting the gene into a bacterium that then inserts its DNA, including the new gene, into a plant cell's DNA,. Tie plant cells with the new gene can then grow into a genetically modified plant. Another technique involves coating the surface of microscopic metal balls with the genetic material to be transferred, and then shooting the balls into plant cells. The DNA sloughs off the metal balls, and the plant cells incorporate it into their own genetic material. When the plant's cellular machinery reads the new gene, it produces a protein that can do one of many things: It can ward off insects, improve the plant's nutritional value, or protect the plant from herbicides, for instance.

Social And Political Fears

The first genetically engineered crops hit the market in the mid-1990's, containing genes that protected plants against insects and herbicides. Those plants already account for around half of all the cotton and soybeans grown in the United States, and one-third of the corn. While many American farmers embrace the technology, reactions from the public have been decidedly negative, especially in Europe (see related article, Page A74).

Many of the worries are social and political. Why should the handful of large biotechnology corporations that have patented these crops exert greater and greater control over the world's agriculture? Are those companies forcing the technology onto consumers and farmers who may not want it, particularly in developing countries? Is it even ethical to patent living things? Is so much attention being focused on biotechnology that other agricultural methods, such as organic farming or integrated pest management, are being ignored? Those concerns should be discussed, say the scientists, but they believe most resistance to genetically engineered crops is born of fear.

People worry that such crops will wreak havoc on the food supply and the environment. Plant scientists say those fears are overblown. "The first thing that gets lost in these discussions is the science," says Mr. Siedow. Take the issue of food safety. No experiments that stand up to scientific scrutiny have found health risks from eating genetically modified foods. Millions of Americans have eaten the foods for several years now, and no problems have been reported. Yet fears of unsafe food still seem to be foremost in the minds of the public. When Peggy G. Lemaux, a cooperative-extension specialist for the University of California at Berkeley, recently gave a talk, an audience member began crying because she found out that the soy formula she fed her baby was made from genetically modified plants.

Ms. Lemaux and other scientists say there are no solid data to suggest that bioengineered foods can make people sick. A widely publicized experiment, in which rats were fed genetically engineered potatoes, has been written off by most scientists as inconclusive. Though the rats suffered damage to their guts and immune systems, scientists believe the problem lay in the potatoes themselves, which produce natural toxins at varying levels, and in the fact that the rats in the experiment were undernourished. Similar experiments, in which rodents were fed bioengineered tomatoes, found no ill effects.

An Allergy Problem

A food-safety concern that scientists take more seriously-but think they can resolve-is the possibility that genetically modified foods can cause allergies. If the gene added to a crop produces an allergenic protein, a previously harmless food could elicit allergic reactions. That has already happened once. In the early 1990's, Pioneer Hi-Bred International, Inc., an Iowa-based seed company, transformed soybeans to produce a protein from Brazil nuts.

When a scientist at the University of Nebraska discovered that the protein was likely to cause allergies, Pioneer Hi-Bred dropped the project. Scientists say that proteins that might cause allergies often get discovered even earlier, preventing any problematic bioengineered foods from being developed, much less marketed. Based on the molecular identity of the protein, scientists often can predict whether it will be an allergen even before engineering a plant to produce it, according to Bob B. Buchanan, a professor of plant and microbial biology at Berkeley. But critics say the strategy is not failsafe.

Rebecca Goldburg, a senior scientist for Environmental Defense, a nonprofit environmental advocacy group, points out that no guidelines exist for dealing with a protein that fails the lab tests. "The question is, what do you do? The company would like to get this protein onto the market," she says.

One of the difficulties in testing for allergenic proteins is that most animals do not experience allergies and so can't be used for experimentation. Mr. Buchanan is trying to develop tests on dogs, whose allergies are similar to those of humans. Even with tests for allergenic proteins still being developed, near-consensus exists among scientists that genetically engineered foods are not hazardous to human health.

"If you take one gene from a soybean and put it into corn, it's not going to make corn any less safe," says Channapatna S. Prakash, the director of the Center for Plant Biotechnology Research at Tuskegee University. He points out that triticale, a widely planted hybrid of wheat and rye, was produced by mating the two crops, adding tens of thousands of genes from rye to wheat. "Traditional varieties were always bred like this, and we never tested them for anything."

Similarly, scientists dismiss concerns that agricultural biotechnology will reduce the planet's biodiversity. Traditional agriculture is just as likely as newer techniques to replace wild ecosystems with single crops, they say.

Evolving Insects

But the scientists pay more heed to some other environmental concerns. Those include the risk of insects' developing resistance to a toxin the crop produces, the same toxin hurting nonpest insects like butterflies, and the spread of a crop's new genes, called transgenes, to other plant species. Many of the bioengineered corn and cotton crops that have been planted are socalled Bt crops, which produce a toxin that kills insect pests. Bt is widely used as a traditional, sprayed insecticide even by organic farmers. It gets its name from the bacterium Bacillus thuringiensis, which naturally produces the toxin. As with any pesticide, if Bt is used long enough, some insects are likely to evolve to be unharmed by it. But because Bt crops produce the insecticide constantly, resistant insects may appear even faster. If they mate with other resistant insects, they may spawn uncontrollable pests.

"It would be a real shame if the efficacy of Bt toxins was squandered on a decade or so of use of transgenic crops," says Environmental Defense's Ms. Goldburg. Research continues on the best way to delay insect resistance. One method, the "refuge" strategy, relies on growing Bt crops near non-Bt crops, so that only a few insects will evolve resistance in the Bt field, while many more will survive without developing resistance by feeding on the refuge crops. The few resistant insects are likely to mate with susceptible bugs, producing susceptible progeny.

The Environmental Protection Agency requires that growers plant at least 20 percent non-Bt crops, a fraction that has been agreed upon by scientific panels from the government, industry, and the Union of Concerned Scientists, as well as researchers working with farmers, according to Fred Gould, a professor of entomology at North Carolina State University. But insecticide-producing crops might also harm wildlife other than the pests they target.

Last spring, much publicity arose around a Cornell University study of monarch-butterfly larvae that fed on milkweed coated with pollen from Bt corn. Although almost half of the caterpillars died, many researchers say the study, which was conducted in a laboratory, has little relevance for butterflies living in the wild, near corn fields. More recent lab studies have found little, if any, danger to monarchs living near the edges of corn fields.

In any case, the scientists point out, Bt was already known to be harmful to butterflies when used as a traditional pesticide. Research continues at several universities on questions such as how far corn pollen might drift from an engineered corn field and how toxic it is to the butterflies. New Bt plants may soon be available that do not produce the toxin in their pollen.

Helping Weeds Survive

The other major environmental concern, that transgenes might move into closely related plants growing nearby, is an important one, according to Norman C. Ellstrand, a professor of genetics at the University of California at Riverside. Since many transgenes help crops survive, by protecting them from insects, for instance, the bioengineered plants could conceivably mate with related plants, including weeds, and make them hardier.

The major crops grown in the United States do not have weedy relatives here, Mr. Ellstrand points out, but it could be a problem for growers elsewhere. "We may be able to anticipate most of the problems with transgenic crops," he says. "We're not talking killer tomatoes. We're talking reasonable risks that can be anticipated." But the studies being done to identify and solve such problems are scant compared with projects aiming to make new engineered plants. "The funding is trivial," complains Mr. Ellstrand.

The Agriculture Department has dedicated $1.5million this year to studying the environmental effects of agricultural biotechnology. By contrast, a Swiss pharmaceutical and agricultural company, Novartis , gave Berkeley's plant- and microbial-biology department $25-million over five years, in a controversial deal supporting basic research on plant genetics. Research on risks would be "a wise use of resources by the people who believe in biotechnology the most," says Margaret Mellon, the director of the Union of Concerned Scientists' agriculture and biotechnology program. "But they really don't act as if they see that it's in their interest to understand the risks of the technology."

What's more, corporate support may have influenced the tenor of the scientists' arguments, others say. "It's very difficult for somebody who has grants from a company to also speak out about any of the uncertainties, because it would threaten research funds," says Sheldon Krimsky, a bioethicist at Tufts University. Of academic scientists' enthusiasm about agricultural biotechnology, he says, "It's hard to know whether or not it's a sincere belief on their part, or whether they have become invested in the same set of values as corporate interests that are heavily funding academic research."

Excitement About Benefits

But many scientists insist that the driving force behind their studies is excitement about how agricultural biotechnology can improve food's nutritional content, create new products such as edible vaccines, and even protect the environment. Already, Bt crops are reducing the use of traditional pesticides long suspected of being hazardous.

According to the National Center for Food and Agricultural Policy-a nonprofit organization in Washington financed by the federal government, charities like the Rockefeller Foundation, and several agricultural-chemical companies-the use of Bt cotton reduced insecticide use by two million pounds in 1998, or 12 percent of the total used nationwide on cotton. However, most of the benefits that might come from genetically modified crops are hypothetical, because the products are still in the pipeline.

"The best stuff is yet to come," says Ray A. Bressan, a professor of horticulture at Purdue University's main campus, who studies the genes that allow some plants to tolerate drought. His research, like that of many other academic scientists, is many years from producing a usable crop, but if successful, it could help subsistence farmers dramatically.

So could research to improve the nutritional value of foods, which is also making headway. In January, European scientists announced that they had created rice containing the substance humans convert to vitamin A, which is deficient in the diets of millions of people. Tuskegee's Mr. Prakash has developed a sweet potato with high protein levels. He hopes to bring his vegetables to the farmers of Vietnam, by working with the International Service for the Acquisition of Agri-Biotech Applications, a nonprofit group that helps interested countries develop appropriate biotechnology-methods.

That group is also working with several countries in Southeast Asia to develop virus-resistant papaya, a widely grown fruit and a source of vitamin A. Currently, according to the group's executive director, Anatole F. Krattiger, about half of the crop in this area is lost to papaya-ringspot virus. A genetically modified strain that resists the virus has already been developed in Hawaii, and the first Asian field trials are under way in Thailand.

Genetic engineering is also being used to create foods with entirely new properties. Some genetically modified foods, far from causing allergies, might actually make them less problematic. Berkeley's Mr. Buchanan has discovered an enzyme from plants that can disarm the allergens that make it impossible for some people to consume wheat or milk. "If we treat the food with our system, the vomit response is greatly reduced," he says.

The process is easy with milk, since the enzyme dissolves in it, but much harder with wheat. So Mr. Buchanan's research team is working to engineer the cereal to produce the enzyme. Mr. Buchanan hopes a similar technique will work for peanut allergies, which can be fatal. Other bioengineered foods might someday replace medicines.

Charles J. Arntzen, the president of the Boyce Thompson Institute for Plant Research, a private, nonprofit organization in Ithaca, N.Y., has already engineered potatoes to deliver vaccines against diarrhea) diseases or against hepatitis B-but only if people eat the potatoes raw. He's now working on making banana and tomato vaccines. Edible vaccines would eliminate the need for injections and the cost of purifying and refrigerating traditional vaccines. What's more, the vaccine-containing plants could be grown in developing countries. Once scientists develop such plants, critics argue, someone will need to deal with the logistics of transporting them and making sure that infants get the proper doses.

Spreading The Word

Academic scientists worry that exaggerated fears about genetic engineering could deny them the chance to use biotechnology tools to improve health and nutrition worldwide. They admit that self interest plays into their hopes for the future: With escalating public concern over genetically modified plants, they could lose grants for their research. "If people could make choices wisely, we could navigate this water," says Ms. McCouch, of Cornell University. "But it does require bringing the public along and making sure that people don't feel anything is being forced upon them that they are fundamentally at odds with."

To that end, the public-affairs committee of the American Society of Plant Physiologists has worked in the past year to involve its members in the public debate over genetically engineered food. "We've encouraged members not simply to write their congressmen, but to write editorials," says Mr. Siedow, who chairs the committee.

Mr. Prakash has drawn up a petition in support of genetic engineering as a "powerful and safe means for the modification of organisms" that can enhance the "quality of life by improving agriculture, health care, and the environment." Four days after he had posted it on the World Wide Web at http://www.agbioworld.org, 600 scientists had signed it.

Now, three months later, more than 1,600 have signed. "There's no question that activity is increasing," says Berkeley's Ms. Lemaux. Scientists can't afford to keep a low profile anymore, she says, and she has worked to galvanize her colleagues to become activists. She keeps on her Web site (plantbio.berkeley.edu/~outreach) text and slides for a generic talk about biotechnology for other scientists to use. "It's not to, quote, support the technology, as much as it is to support the gathering and dissemination of the scientific basis for the technology and its risks and benefits," she says.

Some scientists are encouraged that their message is getting across. Says John W. Taylor, a professor of plant and microbial biology at Berkeley and one of the Oakland demonstrators, "There are some people that are true believers, and I doubt you're going to have much of an effect. But most people will listen to information, and if it makes sense they'll put it in their data bank. And then they'll think about it."