sealPurdue News

April 18, 2002

Terminator tussle: Controversial technology needed, experts say

WEST LAFAYETTE, Ind. – A genetic plant sterilization technology – known as the Terminator gene – that is heralded by scientists as a possible solution to the ecological problem of gene drift is being scorned by many environmentalists.

It's a conundrum that has some scientists scratching their heads.

The United Nations Convention on Biological Diversity, which is being held in The Hague this week (4/15-19), is examining the issue of whether plant sterility genes should be banned internationally. So far, India is the only nation to ban the technology, although the technology is not being used in any nation.

Purdue University bioethicist Paul Thompson says much of the opposition to plant sterilization technology is misplaced fury.

"It's an issue that's not very well understood, and I think environmental groups haven't thought through the potential benefit of the gene," Thompson says. "The important thing that is being overlooked is that incorporating the gene is a good strategy for limiting the environmental impact of genetically modified plants."

Thompson holds the Joyce and Edward Brewer Chair in Applied Ethics in Purdue's Department of Philosophy, and is the author of "Agricultural Ethics: Research, Teaching, and Public Policy" and "Food Biotechnology in Ethical Perspective."

William Muir, professor of animal sciences, has done extensive work on the ecological risk of introducing genetically modified plants and animals into the environment.

Through his research, Muir and Rick Howard, professor of biology, have shown that if a genetically modified plant or animal has a reproductive advantage, such as being larger, it could become an invasive species or even drive the native population to extinction.

"Any ecosystem took billions of years to co-adapt to other species and become established," Muir says. "A major problem with maintaining such an ecosystem is the introduction of exotic plants and animals, as we see with the introduction of things such as zebra mussels and the gypsy moth.

"Genetically modified species are similar in many aspects to exotic species. Genetically modified organisms should only be introduced into wild ecosystems after extensive study of the risk and they are found to be safe. The so-called Terminator technology would bypass this hazard, and the downside of the technology is minor in comparison to the potential benefits."

If a plant sterilization gene is inserted in a genetically modified plant, the plant is unable to produce fertile seeds. Critics of the technology say this is unfair to poor farmers because it prevents them from setting aside a portion of the harvest as seed for the following year and forces them to buy seed each year.

However, farmers in the United States and other industrialized nations don't commonly replant seed from the previous year's crop.

Marshall Martin, associate director of Agricultural Research Programs at Purdue, says that most U.S. farmers do not save seed.

"Farmers cannot save seed from hybrid corn because it will not produce a good yield. Farmers who buy genetically modified soybeans sign an agreement saying they won't save the seed," Martin says. "With crops such as soybean, cotton or wheat, because private companies and land-grant universities continuously develop and release new varieties that offer greater yields and disease resistance, farmers prefer to buy this improved seed rather than save seed from the previous year."

Because of poor profit potential in low-income developing nations, major seed companies don't consider farmers in these countries to be attractive customers, Martin says.

"When they have developed biotech crops for these nations, such as Monsanto did with the disease-resistant sweet potato, they have often given away their discoveries to public institutions," he says. "In the case of the sweet potato, Monsanto gave the discovery to the Ministry of Agriculture in Kenya for further development and distribution. The companies realize they're not going to make much money off of farmers who are growing crops mostly for their families. The transaction costs are fairly high to deliver small amounts of seeds to farmers in remote areas who have limited capital and acreage, so they try to get as much humanitarian and public relations value out of it as they can by giving it away.

"For a seed company there would be limited commercial opportunity for a crop such as sweet potato compared to crops such as corn, soybeans, wheat, cotton, canola, etc., that are grown in many parts of the world by larger commercial farmers."

The large seed companies were interested in plant sterilization technology, also known as trait protection technology, because it would allow them to sell genetically modified seed to farmers without having to enforce a user's agreement. Now, when some farmers violate the user contracts companies must take them to court, which is an expense and detracts from the company's public image.

Drew Kershen, who is the Earl Sneed Centennial Professor of Law at the University of Oklahoma College of Law, says scientists in the U.S. Department of Agriculture and in Delta and Pine Land Company first developed trait protection genes as an environmental protection technology in 1993.

When the patent for the gene was issued in 1998, some companies, particularly Monsanto, were interested in licensing the patented technology. This interest melted away in face of the controversy, and no crops containing the plant sterilization genes were ever put on the market.

"After environmental groups campaigned vigorously against trait protection systems, the United Nation's Food and Agriculture Organization declared it an immoral technology," Kershen says. "As a result, scientists who work with the Consultative Group on International Agricultural Research adopted a policy prohibiting the use of the technology in their breeding programs. The FAO decision was a political decision not based on understanding neither the science nor the environmental benefits of trait protection systems.

"This occurred despite the fact that the USDA scientists who created the genes envisioned the technology as a means of preventing an unwanted spread of transgenic traits into weedy relatives of crop plants and into other non-transgenic crops. Delta and Pine Land Company continues to develop trait protection technology."

Thompson says the Terminator technology has garnered more than its share of attention.

"Terminator has captured the public's attention unlike any other form of biotechnology out there," he says. "I have no idea why that is. My speculation is that making a seed sterile goes against some basic sense of what's right."

But Thompson says it may be the Terminator label itself that caught the public eye.

The Terminator name was given to the technology by anti-biotechnology interest groups. The scientists who developed the gene originally gave it the name "control of gene expression." Thompson says the Terminator tussle is just one example of how language has been used to misconstrue science.

"This happens on both sides of the biotechnology debate," he says. "On the one hand you have some groups using scare tactics and using labels such as Terminator or Frankenfoods. On the other hand you have corporate public relations departments doing massive consumer attitude research to come up with names for the products that get people to think about the products in cuddly and friendly terms.

"Either way you're manipulating the issue rather than addressing it."

When the U.S. Department of Agriculture examined the issue of the Terminator gene in 2000, there was disagreement between the scientists and the environmental groups, says Martin, who was a member of the USDA Agricultural Biotechnology Advisory Committee when it examined the issue.

"The majority view of those of us on the USDA committee was that we should go forward with research on the technology," he says. "But all of the public comments that we received from the environmental groups were opposed."

Because the technology would seem to prevent an environmental problem, some people in agriculture have suggested that the issue of plant sterilization genes is a stalking horse – that these groups are opposed to the technology simply because they oppose any type of genetic modification.

"If an environmental group gets to the point where it is trying to make the technology as dangerous as possible to stop people from using it, that strikes me as a cynical approach," Thompson says. "If we shouldn't be doing any genetic engineering of plants, we should be making that argument on the merits. We should not encourage reckless policy decisions that make biotechnology more dangerous."

Writer: Steve Tally, (765) 494-9809;

Sources: Paul Thompson, (765) 494-4295,

William Muir, (765) 494-8032;

Marshall Martin, (765) 494-8365;

Drew Kershen, (405) 325-4784;

Ag Communications: (765) 494-2722; Beth Forbes,;

Purdue News Service: (765) 494-2096;

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