Genes From Engineered Grass Spread for Miles, Study Finds

By Andrew Pollack
NY Times
September 21, 2004

A new study shows that genes from genetically engineered grass can spread much farther than previously known, a finding that raises questions about the straying of other plants altered through biotechnology and that could hurt the efforts of two companies to win approval for the first bioengineered grass.

The two companies, Monsanto and Scotts, have developed a strain of creeping bentgrass for use on golf courses that is resistant to the widely used herbicide Roundup. The altered plants would allow groundskeepers to spray the herbicide on their greens and fairways to kill weeds while leaving the grass unscathed.

But the companies' plans have been opposed by some environmental groups as well as by the federal Forest Service and the Bureau of Land Management. Critics worry that the grass could spread to areas where it is not wanted or transfer its herbicide resistance to weedy relatives, creating superweeds that would be immune to the most widely used weed killer. The Forest Service said earlier this year that the grass "has the potential to adversely impact all 175 national forests and grasslands."

Some scientists said the new results, to be published online this week by the journal Proceedings of the National Academy of Sciences, did not necessarily raise alarms about existing genetically modified crops like soybeans, corn, cotton and canola. There are special circumstances, they say, that make the creeping bentgrass more environmentally worrisome, like its extraordinarily light pollen.

Because Scotts has plans to develop other varieties of bioengineered grasses for use on household lawns, the new findings could have implications well beyond the golf course. And the study suggests that some previous studies of the environmental impact of genetically modified plants have been too small to capture the full spread of altered genes.

Scotts says that because naturally occurring bentgrass has not caused major weed problems, the bioengineered version would pose no new hazards. And any Roundup-resistant strains that might somehow develop outside of intentionally planted areas could be treated with other weed killers, the company said.

In the new study, scientists with the Environmental Protection Agency found that the genetically engineered bentgrass pollinated test plants of the same species as far away as they measured -about 13 miles downwind from a test farm in Oregon. Natural growths of wild grass of a different species were pollinated by the gene-modified grass nearly nine miles away.

Previous studies had measured pollination between various types of genetically modified plants and wild relatives at no more than about one mile, according to the paper.

"It's the longest distance gene-flow study that I know of," said Norman C. Ellstrand, an expert on this subject at the University of California, Riverside, who was not involved in the study but read the paper.

"The gene really is essentially going to get out," he added. "What this study shows is it's going to get out a lot faster and a lot further than people anticipated."

One reason the grass pollen was detected so far downwind was the size of the farm - 400 acres with thousands of plants. Most previous studies of gene flow have been done on far smaller fields, meaning there was less pollen and a lower chance that some would travel long distances. Those small studies, the new findings suggest, might not accurately reflect what would happen once a plant covers a large area.

"This is one of the first really realistic studies that has been done," said Joseph K. Wipff, an Oregon grass breeder. Dr. Wipff was not involved in the latest study but had conducted an earlier one that found pollen from genetically engineered grass traveling only about 1,400 feet. That test, though, used less than 300 plants covering one-tenth of an acre.

The effort to commercialize the bentgrass has attracted attention because it raises issues somewhat different from those surrounding the existing genetically modified crops.

It would be the first real use of genetic engineering in a suburban setting, for example, rather than on farms. And the grass is perennial, while corn, soybeans, cotton and canola are planted anew each year, making them easier to control.

Bentgrass can also cross-pollinate with at least 12 other species of grass, while the existing crops, except for canola, have no wild relatives in the places they are grown in the United States. And crops like corn and soybeans have trouble surviving off the farm, while grass can easily survive in the wild.

The bentgrass, moreover, besides having very light pollen - a cloud can be seen rising from grass farms - has very light seeds that disperse readily in the wind. It can also reproduce asexually using stems that creep along the ground and establish new roots, giving rise to its name.

Because of the environmental questions, the application for approval of the bioengineered bentgrass is encountering delays at the Department of Agriculture, which must decide whether to allow the plant to be commercialized.

After hearing public comments earlier this year, the department has now decided to produce a full environmental impact statement, which could take a year or more, according to Cindy Smith, who is in charge of biotech regulation.

Ms. Smith, in an interview yesterday, said the new study "gives some preliminary information that's different from previous studies that we're aware of." But more conclusive research is needed, she said.

Bentgrass is already widely used in its nonengineered form by golf course operators, mainly for greens but also for fairways and tee areas, in part because it is sturdy even when closely mown. It is rarely used on home lawns because it must be cared for intensively. And creeping bentgrass does not cross-pollinate with the types of grass typically used on lawns, scientists said.

Executives at Scotts, a major producer of lawn and turf products based in Marysville, Ohio, said the genetically engineered bentgrass would be sold only for golf courses. They said golf courses cut their grass so often that the pollen-producing part of the plants would never develop.

And because nonengineered creeping bentgrass has not caused weed problems despite being used on golf courses for decades, they said, the genetically modified version would pose no new problems.

"There has been pollen flow but it has not created weeds," Michael P. Kelty, the executive vice president and vice chairman of Scotts, said in an interview yesterday. He said Scotts and Monsanto, the world's largest developer of genetically modified crops, had spent tens of millions of dollars since 1998 developing the bioengineered bentgrass.

The questions about the grass come after Monsanto, which is based in St. Louis, said earlier this year that it was dropping its effort to introduce the world's first genetically engineered wheat, citing concerns by farmers that its use in foods might face market opposition.

Scotts is also developing genetically modified grass for home lawns, like herbicide-tolerant and slow-growing types that would need less mowing. But those products still need several more years of testing, Dr. Kelty said, adding that the company would avoid types of grass that could become weeds. "We don't want to put a product out there that is going to be a threat," he said.

Scotts and Monsanto have received some support for their argument from the Weed Science Society of America, a professional group, which conducted a review of the weed tendencies of creeping bentgrass and its close relatives at the request of the Department of Agriculture.

"In the majority of the country these species have not presented themselves as a significant weed problem, historically," said Rob Hedberg, director of science policy for the society, summarizing the conclusions of the review. He said that because people have generally not tried to control bentgrass and similar species with Roundup, known generically as glyphosate, "the inability to control them with this herbicide is a less significant issue."

Still, the society's report noted that bentgrass could be considered a weed by farms that are trying to grow other grass seeds. And the Forest Service, in comments to the Agriculture Department earlier this year, said that bentgrass has threatened to displace native species in some national forests.

John M. Randall, acting director of the Invasive Species Initiative at the Nature Conservancy, said bentgrass and related species had been a threat to native grasses in certain preserves that the group helps manage, including a couple near Montauk Point on eastern Long Island.

Other opponents of the genetically modified grass seized on the results. "This does confirm what a lot of people feared - expected, really," said Margaret Mellon, director of the food and environment program for the Union of Concerned Scientists in Washington. "These kinds of distances are eye-popping."

The new study was done by Lidia S. Watrud and colleagues at an E.P.A. research center in Corvallis, Ore., who were trying to develop new methods to assess gene flow, not specifically to study the bentgrass.

They put out 178 potted and unmodified creeping bentgrass plants, which they called sentinel plants, at various distances around the test farm. They also surveyed wild bentgrass and other grasses. They collected more than a million seeds from the plants, growing them into seedlings to test for herbicide resistance and doing genetic tests.

The number of seeds found to be genetically engineered was only 2 percent for the sentinel plants, 0.03 percent for wild creeping bentgrass and 0.04 percent for another wild grass. Most of those seeds were found in the first two miles or so, with the number dropping sharply after that. Still, said Anne Fairbrother, one of the authors of the report, finding even some cross pollination at 13 miles "is a paradigm shift in how far pollen might move."

Fear of Pharming

By Alla Katsnelson
Scientific American
September 20, 2004

Controversy swirls at the crossroads of agriculture and medicine

Farming, one of the world's oldest practices has suddenly found itself entangled with modern medicine. Imagine this: at your child's appointment for a routine vaccination, the doctor proffers a banana genetically engineered to contain the vaccine and says, "Have her eat this and call me in the morning." Though still far-fetched, the scenario is getting closer to reality, with the first batch of plant-made medicines--created by genetically modifying crops such as corn, soy, canola and even fruits such as tomatoes and bananas to produce disease-fighting drugs and vaccines--now in early clinical testing.

Splicing foreign genes into plants is nothing new--biologists have been doing it for about 25 years. Using the technology to produce protein-based medicine could revolutionize the drug industry, proponents say. Plants are inherently safer than current methods of using animal cell cultures, which carry a risk of spreading animal pathogens; plants also provide a much cheaper means of production. But fears that these "pharma crops" will contaminate the food supply are casting shadows on the promise of the technology.

The problem is that containing genes from GM plants seems to be harder than scientists expected. Recent data suggest that bioengineered genes spread more widely than previously thought. A pilot study released in February by the Union of Concerned Scientists (USC) found that more than half of native species of corn, soybean and canola tested contained low levels of DNA from strains engineered to confer resistance against herbicides. An analysis published in March established that genetically engineered corn had found its way into Mexico despite that country's six-year-old ban on growing GM varieties of the crop. And a major review of biologically modified organisms conducted last year by the National Academies of Science stressed the need to develop better confinement techniques. These findings and others illustrate the reality that experts are starting to acknowledge: the way things are going, maintaining zero levels of contamination from GM plants may be impossible.

Leaks of pharma crops have occurred as well. Two years ago, USDA inspectors found experimental corn plants containing a pig vaccine growing in nearby conventional fields in two separate incidents in Nebraska and Iowa. ProdiGene, the Texas biotech company responsible for the mishaps, was heavily fined for violating its permit and ordered to destroy 500,000 bushels of soybeans and 155 acres of corn plants. But perhaps more importantly, the leak shook the public's confidence in the technology. So far, no one has shown that current GM crops carry any health risks. But pharma crops, the new generation of GM plants, raise the safety stakes: the proteins spliced into these plants are specifically chosen to target physiological function.

The USDA Animal and Plant Health Inspection Service (APHIS), which oversees crops, responded to the ProdiGene incident by revising its regulations for growing pharma crops. Companies must now use designated equipment for planting and harvesting, provide better crop containment training for growers, and undergo at least five inspections a year. The new rules also require that pharmaceutical corn be grown at least one mile away from any other fields and planted at least 28 days before or after surrounding corn crops are planted. Lisa Dry, spokeswoman for the Biotechnology Industry Organization (BIO), says the new rules make drug pharming so distinct from producing commodities crops that future contamination is preventable. And industry, keen to avoid any further negative publicity, takes contamination very seriously. In fact, according to Neil Johnson, regulatory programs director at APHIS's Biotechnology Regulatory Services, many if not most companies running field tests for pharma crops currently operate under tighter restrictions than government regulations demand.

But even with stringent compliance by industry, the science of gene flow could flout APHIS's rules. Corn in particular, which accounts for about two thirds of pharmaceutical crops being tested, has a strong tendency to cross-pollinate. "Corn is the world's worst organism for this," says Norman Ellstrand, a plant geneticist at the University of California at Riverdale and director of the Biology Impacts Center. "When I heard about this, my first thoughts were, 'What were they thinking?'" Corn pollen is viable for only a few days, and the 28-day segregation requirement provides a good deal of additional protection against contamination. But the problem, Ellstrand observes, is that there is little actual data on how far genes can travel.

"We're working on isolation standards based on research done in the 1950's," declares Joseph Burris, an emeritus professor of seed science at Iowa State University who now owns a consulting company specializing in gene containment issues. "A lot of things have changed." More recent work is starting to suggest that genes can travel farther than previously thought. One report presented at the First European Conference on the Co-existence of Genetically Modified Crops with Conventional and Organic Crops last November found viable corn pollen as high up in the atmosphere as 2,000 meters. If pollen is present that high, the researchers say, there may be a chance that it can spread over dozens of kilometers if there is enough convection to maintain it aloft. "Our fields are factories without walls. We can't control the environment," Burris asserts. "With isolation distances of [1 mile], our odds of having a problem are very much reduced, but they are not eliminated."

On the other hand, says Michael Pauly of the Chicago-based biotech company Chromatin Inc., current techniques for detecting gene contamination, such as PCR, which measures DNA levels, may be too sensitive for our own good. (Chromatin is developing a novel technique for inserting drug-producing genes into plants.) "You can detect a level of DNA that doesn't actually reflect risk," he explains. Indeed, people and animals ingest foreign DNA with every hamburger they eat. "It's not the nucleic acid that's the problem, but the protein," he says, because it is protein, not the DNA itself, that has a biological effect. Burris, too, notes that the improvement in detection technology has essentially redefined contamination. "We've gotten so abstract about zero contamination. I don't even know what that means," he says.

Many researchers, as well as groups including the Union of Concerned Scientists, the Food Manufacturers of America, and the Consumer Union, contend that the only measure sufficient to ensure zero contamination by pharmaceutical crops would be to avoid developing the technology in plants that can find their way into the stomachs of people or farm animals. But the biotech industry bristles at the suggestion, countering that oilseed crops such as corn not only provide the best medium for obtaining a high level of very pure protein, but are also safer because they are so well studied. "These are the crops that have formed the basis of our culture, our civilization, our economy. This is our knowledge base, and that is fundamentally enabling," Pauly insists.

A consensus about how worried people should be about contamination seems unlikely to emerge in the near future. When it comes to the risk of drugs making their way into the food supply, says Ellstrand, "I wouldn't say zero tolerance for all pharmaceuticals, because presumably some of those things would be totally benign if they got into the food supply." Those products that might not be harmless, he advises, "should be put into non-foods, grown inside of buildings, or simply shouldn't be created in plants at all." Margaret Mellon, head of UCS's food biotechnology program, disagrees. "We can't have a policy which only allows safe drugs in our food. It has to be no drugs."

Scientists Engineer Mosquitoes That Can't Cause Malaria Infection

By Rhiannon Edward
September 23, 2004

Scientists are genetically engineering mosquitoes in an attempt to wipe out malaria, the disease responsible for more deaths worldwide than any other.

Anthony James, a professor of microbiology and molecular genetics at the University of California, whose lab is working on mosquitoes that cannot host the malaria parasite, said some strains are now ready to be tested outside the lab.

Speaking at the Biotech Bugs conference in Washington DC, sponsored by the Pew Initiative on Food and Biotechnology, Prof James said his team has been working on "introgressing" genes for malaria resistance into existing populations of mosquitoes. The theory of the work is that such genes introduced at high enough frequencies will decrease transmission and result in less disease and death from malaria, possibly even bringing an end to it.

The research is timely as the emerging insecticide resistance of mosquitoes is crippling some of the once-effective approaches used to control them, such as spraying.

Malaria is caused by any one of four species of one-celled parasites called plasmodium. The parasite is spread to people by the female anopheles mosquito. The World Health Organisation estimates that about 1.3 million people die from the disease annually.

Prof James said public concern about the release of genetically modified organisms into the wider environment needed to be addressed before his work could be taken into the field.

He said: "I think we have reached quite a critical point in the development and use of these organisms. We need to identify the next level in this whole adventure. What we need to do is develop a catalogue of what the concerns are. Scientists are going to have different lists from people who do legal work, people who are ministers of health, people who are looking for votes."

But scientists have a history of getting it wrong, even as they try to save the world from insect-borne scourges, said entomologist Fred Gould of North Carolina State University. "In the late 1940s entomologists had no reason to doubt that DDT would cure the world’s pest problems," he told the conference.

DDT, it turned out, affected a range of animals and drove some bird species to near-extinction by weakening their eggshells.

"In the 1960s, advocates of biological control did not consider that imported predators of insect pest species might cause extinction of rare species," Mr Gould added.

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