By Anna Merlan
By Anna Merlan
By Julie Seabaugh
By Jon Campbell
By Albert Samaha
By Anna Merlan
By Alex Distefano
By Scott Snowden
Starting this summer, thousands of genetically modified insects could be released in Arizona. Assuming that scientists get the green light from the government, this field test will mark the first time a GM bug has been let loose in the U.S.
The critter in question is a tinkered-with version of the pink bollworm, a moth whose larvae have a distressing appetite for cotton. Most prevalent in the Southwestern states, this archenemy of the "fabric of our lives" tears through 20 to 50 percent of each crop it infests, leading to millions of dollars in losses each year. It's been causing problems in the U.S. since 1917, when bollworm larvae hitched a ride in some cotton brought into Texas from Mexico. Since then, growers have waged an all-out war. In the latest salvo against the bug, scientists have come up with a plan to introduce a "self-destruct" gene into the population. The goal is complete eradication.
These scientists insist they're not trespassing on virgin territory. "The bollworm has been spread because of mankind's intervention," says Dr. Thomas Miller, the lead scientist for the project, which is being run with the Department of Agriculture's Animal and Plant Health Inspection Service (APHIS). Speaking from his office at the University of California, Riverside, the entomology professor emphasizes, "Mankind is responsible for sending the bollworm all over the world. We're just using nature to correct the problem."
The situation may not be that simple, warns Dr. Jane Rissler, a senior staff scientist in the Food and Environment division of the Union of Concerned Scientists. Her group doesn't consider genetic engineering inherently unnatural, but argues that each case needs to be looked at closely. Still waiting to see all the research on the pink bollworm, Rissler says she's not inclined to endorse the release of GM bugs. "Insects raise a lot of issues," she says. "They reproduce often. They're small, and they occupy a lot of ecological niches.
"Besides the risks, we also need to examine the benefits," Risler adds. "Is this really the best solution? So far, genetic engineering isn't contributing very much to agriculture."
Phase one of the APHIS effort involves giving the bollworms an enhanced gene from a jellyfish, which causes them to turn bright green when placed under a certain kind of light. This marker will allow scientists to tell which bollworms carry the identifying trait. Scientists will study whether the GM bollworms survive in the semi-wild enclosure, whether they live as long and attempt to mate as much as their non-GM counterparts.
Researchers will move to a second phase of the project, in which they'll give bollworms a self-destruct gene. This second bit of DNA will cause any eggs produced in mating with normal bollworms to be duds. Scientists believe that by continually releasing the barren bug throughout the growing season, they can wipe out the general population. The approach could applied to other pests, including that bane of farmers, the Mediterranean fruit fly.
A crucial step in this processand, actually, an enormously important event for all of usis the scheduled release this summer. If the government gives its nod, starting this July 15 and continuing for a year, scientists will turn loose 2350 adult GM bollworms under enclosures in a cotton field in Phoenix, Arizona, to see how they fare under real-world conditions. No more than 300 will flit at any one time through the three-acre testing area. The three pens, designed to keep the creatures from flying away, consist of a mesh-fiberglass screen over a galvanized-pipe frame.
According to the application submitted to the division of APHIS that grants permission for releases, "The potential for escape from the three field cages will be minimal, barring a major weather catastrophe."
To further prevent the escape of the bollworms, sticky traps scented with sex hormones will be set immediately outside the cages to catch stray males, and the female moths will have their left wings removed. What's more, the bollworms released in the experiment's first phase will be sterilized with a dose of radiation. "If one escapes, it's not going to do anything," Miller says. "It's going to die."
On their way to the field, the moths will be transported in containers that don't exactly seem industrial grade. The official application says the bugs will be kept in "shatter-resistant capped plastic vials or sealed cardboard cup-type containers. The lids on each of these containers will be further secured with tape. Additionally, the containers will be transported in a cardboard box lined with Styrofoam and sealed with a nylon strap."
Asked if the scientists could get their application approved in time for the proposed July 15 release, Rissler declares, "They won't make it." The wheels of bureaucracy turn at a snail's pace, and that's just fine with her. She wants the FDA to convene panels to study the issue. "It would behoove the government to act very slowly and deliberately regarding thiscarefully, slowly, and deliberately."
If the bollworm field test isn't approved in time for summer, it'll have to wait until the cotton-growing season next summer. Though that would allow more time for debate, it's important to note that some mutated animals have already left the labs where they were created. Rissler says that GM nematodes (a tiny worm) and mites (similar to insects but technically arachnids) have been released. "Some genetically engineered fish have also been released, but only in isolated ponds," she says.