QUOTE OF THE WEEK:
"...the lure of this technology is so great that much, more meaningful, work has been displaced. In essence, I regard our present direction regarding transgenics as an enormous, and enormously expensive, gamble."
- Andrew Spielman, professor of Tropical Public Health, Harvard University
Frankenbugs in the Wings
By Jeffrey Benner
Dec. 7, 2001
While the nation's attention was occupied by war and terrorism, U.S. scientists quietly conducted the world's first confined field test of a genetically modified insect.
In October, hundreds of genetically modified moths were released into an Arizona cotton field. The test is bound to stir up controversy: It is a big step toward extending the frontier of genetic manipulation beyond plants and into the wild kingdom of insects.
"This first permit has opened the door," said Robert Rose, a regulator with the U.S. Department of Agriculture who gave the go-ahead for the historic test. Rose expects other scientists working with genetically modified insects, including malaria- carrying mosquitoes, to test their bugs in field cages soon.
The tightly controlled release -- the moths were sterilized and confined to mesh cages -- was conducted in October under strict security at a USDA facility in Phoenix. Afraid of attacks by radical environmentalists like the Earth Liberation Front, the four field cages were fenced off and placed under guard. But with all eyes on anthrax and Afghanistan, the tests went unreported and activists stayed home.
"No one bombed us," said Tom Miller, the University of California, Riverside entomologist who bred the pink bollworms used in the test. "It happened after September 11th. We went off the radar screen."
The researchers were testing the breeding ability of hundreds of genetically modified pink bollworms. The moths contained a jellyfish gene that makes them glow green. The glowing gene is a common "marker gene" that tests the moth's ability to mate; any offspring have a glow that's easy to spot.
Eventually, the researchers hope to substitute the harmless jellyfish gene with a lethal one, taken from a bacterium, that will kill the moth's larvae. The gene alters the larvae's metabolism to make them reliant on a chemical unavailable in the wild. The researchers hope genetically modified moths will compete successfully with fertile moths in the race for mates, and will decimate the population by producing larvae that can't survive outside a lab.
The pink bollworm is one of the most destructive cotton pests in the world; every year the insect's larvae cause millions of dollars' worth of damage to the cotton crop. It is controlled only by the liberal application of harmful pesticides.
The October bollworm test was in a cage, but an open field release of a genetically altered bug is probably only a few years way, according to government officials and scientists working in the field.
Although it has not yet received a formal application, the USDA is already planning to prepare an Environmental Impact Statement for an open field test of the pink bollworm. "We want to anticipate the public concerns," USDA's Rose said. The first public meetings on the issue are tentatively scheduled for next summer.
But the prospect of releasing genetically modified insects into the wild is something that makes environmentalists shudder.
Environmentalists say there is no way to predict a modified gene's effect on an ecosystem, and, once it's out, there's no way to get the genie or demon -- back in the bottle. Genetic changes could "jump" to related species, or lead to new diseases, environmentalists warn. Genetic modifications may have unforeseen consequences, like the discovery that genetically modified corn can kill monarch butterflies (although recent research reached the opposite conclusion). And a furor erupted when it was discovered that Starlink corn -- a genetically modified plant not approved for human consumption - - had crept into the food supply.
"We oppose any release of genetically modified organisms into the wild," said Craig Culp, a Greenpeace spokesman. "There's no way to anticipate what will happen generations down the road."
Tom Miller, the bollworm experiment's lead entomologist, defended lethal genes as a safe, cheap alternative to pesticides. "The public has been up in arms for 40 years now about pesticide use," he said. "You have to control (pink bollworm) somehow, and this is an alternative."
Miller said this particular genetic modification was safe because the genetic code could be passed only to one generation: The larvae die before they mature to breeding age. "This is designed to be the softest use imaginable," he said. "We're putting out insects that are supposed to die."
The genetically modified bollworm's breeding limitation is part of the reason scientists working with agricultural pests like the pink bollworm are years closer to open field tests than their counterparts working on disease-bearing insects like the mosquito.
Efforts at controlling diseases like malaria have focused on altering the genetic makeup of the entire disease-carrying species. Releasing genetic modifications that could affect the entire species have far more sweeping, and irreversible, effects on the ecosystem than Miller's bollworm moths.
Nevertheless, the first transgenic mosquitoes that can pass genetically modified traits to offspring were successfully created in the lab just this year, prompting scientists in the field to start pondering a release into nature.
"Now that we have them, we can start considering moving them into the wild," said Tony James, a biology professor at the University of California, Irvine who created the world's first transgenic mosquito in 1998.
James and his colleagues in the field held two groundbreaking conferences this fall -- one in Britain, the other in Atlanta -- dedicated to assessing the risks of a release. They were the first formal meetings held on the topic. It was a significant step, but many obstacles remain. "No one is confident now any release should be done," James said. "I think we're still decades away from a safe release."
But unintended consequences aren't the only risk. Andrew Spielman, a professor of Tropical Public Health at Harvard University, is concerned that the resources used to study genetically modifying mosquitoes could be used more effectively elsewhere, particularly in the study of mosquito ecology and its relationship to malaria.
"I do have reservations about the current focus on transgenic insects," Spielman wrote in an e-mail, "because the lure of this technology is so great that much more meaningful work has been displaced. In essence, I regard our present direction regarding transgenics as an enormous, and enormously expensive, gamble."