While the nation's attention was occupied by war and
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."