Gene-Altered Catfish Raise Environmental, Legal Issues
Science: Modified plants and animals could wipe out other species, experts fear. Oversight is 'full of holes.'
By AARON ZITNER, Times Staff Writer
Electric wire keeps the raccoons at bay. Netting blocks the herons from swooping in. Filters stop the fish from slipping out with the waste water.
Federal officials asked Dunham to protect the local environment from the catfish he grows here because nothing like them has ever cut the waters of the Earth. These catfish have been laced with DNA from salmon, carp and zebrafish, which makes them grow as much as 60% faster than normal. That could help farmers feed more people for less money and boost efforts to end world hunger.
But there also is a chance that fast-growing fish might touch off an environmental disaster, according to scientists who have studied the matter. Their greatest fear is that Dunham's catfish will escape and wipe out other fish species, as well as the plants and animals that depend on those fish to survive.
And now, some scientists and government officials are raising a second and equally troubling concern: that the federal government has limited legal authority to protect the environment from Dunham's catfish--or from some of the dozens of other genetically modified plants and animals now being readied for market.
"Here we are on the brink of remaking life on Earth through genetic engineering, and we do not have a thorough process for reviewing the environmental impacts," said William Brown, science advisor to Interior Secretary Bruce Babbitt. "The system is full of holes."
"My sense is that the current system is not going to be OK and that there are going to have to be changes--or a whole new system put in," said Bill Knapp, a senior fisheries official with the U.S. Fish and Wildlife Service.
This view is far from universal. But concerns about the government's legal authority are significant enough that President Clinton ordered federal agencies in May to review the relevant laws and probe for holes. The review is due to be completed early this month.
Americans already eat modified corn, potatoes and other crops. Soon to come are the first such animals: disease-resistant shrimp, meatier chickens and fast-growing salmon. Thanks to mouse DNA, a new pig produces a less harmful manure. New crops include a rice, mixed with daffodil DNA, that includes more nutrients.
Dunham, an Auburn University researcher, already has started seeking federal approvals to sell his fish. And he could be among the first to win approvals to sell a genetically modified animal to American consumers.
Although there has been great attention paid to whether these foods are safe to eat, Brown and others say the potential risk to the environment could be an even bigger concern. And, the government is stretching outdated laws to cover the gene revolution, they say, as if using 19th century railroad laws to regulate airlines.
Some warn that genetically modified plants and animals could move into the wild and breed disruptive traits into local species, similar to the way African "killer bees" escaped a Brazilian research facility in 1957 and spread their aggressive traits. Others fear an opposite scenario: that instead of thriving, the modified plant or animal could interbreed with its natural cousins in ways that would destroy the species entirely.
Scientists call this the "Trojan gene" effect, because the modified organism is undermined by the new genes that it takes in. William M. Muir, a geneticist at Purdue University, has used a mix of laboratory observation and computer modeling to show that it could happen with gene-altered fish.
Fast-growing fish might enjoy a mating advantage in the wild, Muir says, yet produce young that are ill-equipped to survive. "This could locally take a population to extinction," he said.
And yet, federal officials say that no law requires people who alter fish genes to keep the fish isolated and away from local waters. The Agriculture Department was able to ask Dunham to build his "fish prison" only because his research is backed by federal funds.
Moreover, officials said, it is unclear whether any federal law penalizes a person who releases genetically modified animals into the wild.
More troubling to some critics is that certain species may escape federal regulation entirely.
For example, at least one company is altering the genes in creeping bentgrass, a common golf course turf, so that it is more resistant to weed killers. That would allow lawn managers to use herbicides without harming the turf. But it could also make the grass, which already invades lawns and gardens, harder for homeowners to control.
Officials are divided over whether the government has the authority to regulate genetic changes to the grass. The Agriculture Department claims authority over all "plant pests" and potential pests, and it is using that authority to supervise the company working on creeping bentgrass genes. But Brown and others disagree, saying that the legal definition of plant pests clearly excludes the grass. The department has overstepped its legal authority, Brown says.
Similarly, several teams are working to modify algae as a food and laboratory substance, said Anne Kapuscinski, a fish geneticist at the University of Minnesota. Algae is not a plant pest, she said, "so who is going to have authority over it? There's been no public statement on that."
The confusion arises because the government, starting with the Reagan administration, decided that decades-old food and agriculture laws could be stretched to cover genetically altered species.
For example, some corn and potato varieties already on the market have been genetically modified to produce their own insecticide. Because the Environmental Protection Agency has jurisdiction over insecticides, it takes a lead role in regulating these crops.
For other crops, the Agriculture Department claims a leading role because scientists commonly use bacteria and viruses to modify the crop genes. The agency already regulates those bacteria and viruses as plant pests, and it claims jurisdiction over the crops as well.
Jane Rissler, senior staff scientist with the Union of Concerned Scientists, called this rationale "an awkward stretch of the laws" that does not cast a broad net over all gene-altered plants. The mere fact that genes have been engineered should be enough to bring a plant or animal under federal scrutiny, she said.
Besides, scientists now are modifying genes in ways that do not rely on bacteria or viruses but that should not release them from federal regulation, Rissler said.
In regulating fish, some people believe the laws are being stretched in equally awkward ways.
Dunham had spent years using traditional breeding techniques to modify the channel catfish, which is by far the most farmed fish in the United States.
Then, in 1982, American scientists created one of the first transgenic animals--mice that grew to twice their normal size, thanks to rat and human genes that produce growth hormone. The mouse experiment prompted other scientists to start manipulating traits in a range of species. Many researchers saw the new technology as a way to help farmers produce more food with less resources.
"If we can grow more fish in less space, that decreases pressure on the environment," Dunham said. "And we will never be able to catch more fish than we do now from the natural environment. Yet world demand for fish is increasing."
Normally, catfish stop growing in the winter, when the genes that produce growth hormone all but shut down. Dunham and his team began producing catfish that had an extra copy of a growth hormone gene. They also added a piece of DNA from salmon, carp or other species that acts like a year-round "on" switch for the gene.
The result: Dunham's catfish grow to their market size of about 2 pounds within 12 to 18 months, rather than the normal 18 to 24 months.
Dunham and his research partner, Zhanjiang "John" Liu, hope to turn the fish into a commercial product. Several fish geneticists believe the Auburn catfish could be the second genetically modified animal to reach American consumers. A/F Protein Inc., a Massachusetts firm, is expected to be first. It is seeking approval for a fast-growing salmon that it is developing in indoor tanks in Canada.
Dunham and Liu also have begun researching how their fish would behave in the wild. So far, they say, they have found no cause for concern.
One published study found that the fish have slightly less ability to avoid predators than do native catfish. Two other studies, not yet published, determined that the Auburn catfish do not have a competitive edge over native fish for food and have equal reproductive ability.
"What it points to is that these fish have no environmental advantage, or maybe are a little handicapped in the natural environment," Dunham said. "But the principal point is that we need more research to determine what the environmental risk is."
If Dunham and Liu commercialize the catfish, the lead regulator would be the Food and Drug Administration--but not because the fish would be a food. Instead, the agency considers the fish's extra growth hormone to be a drug.
But some wildlife experts say that, although the FDA is well-equipped to assess drugs, it is the wrong agency to rule on whether genetically modified fish pose a risk to the environment. "People understand intuitively that this is asking a lot of the FDA, asking it to become a wildlife regulatory agency," Brown said.
FDA officials say they are routinely called on to consider environmental effects. John Matheson, senior review scientist for veterinary medicine, noted that, when the agency recently reviewed a growth hormone for cows, it studied potential changes in land-use patterns, soil erosion and methane levels.
Critics of the system raise another complaint about the FDA's role: It operates under a federal law that aggressively protects company trade secrets, and an often anxious public cannot learn what genetically modified plants and animals are on the road to winning federal approvals.
"If there was a chance to look at the process and contribute to the decision-making, it would be a lot easier to win over the trust of the public," Kapuscinski said. "You'd still have some criticism, but you'd have more trust."
Copyright 2000 Los Angeles Times