First GM insect release set to get go-ahead
Friday, 9 February, 2001, 10:08 GMT
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1150000/1150796.stm
The pink bollworm is a major pest of cotton worldwide
By BBC News Online's Helen Briggs
The first release of a genetically modified insect is expected to take
place in the United States this summer.
A moth has been engineered to contain a gene from a jellyfish in the
first stage of a genetic experiment designed to eradicate the
cotton-destroying pest from the wild.
A total of 3,600 of the moths will be set free under a cage within a
one-hectare (three-acre) cotton field in Arizona.
The experiment is likely to raise
concern among environmental
groups.
But the researchers behind it say
there is "minimal" risk of the
genetically modified insects
escaping. As an added precaution,
the insects have been sterilised.
Pink pest
Thomas Miller of the Department of Entomology, University of
California, told BBC News Online: "It is very important for us that
the public understands what we're doing and why. We are not trying
to create something that causes more trouble than we already have.
"We have plenty of trouble with pink bollworm. It's an absolute
nightmare and it's caused a lot of people to go bankrupt.
"There's two things about this release. Number one, we're only
going to use sterilised insects in the first go around. Even if they
get out, there's no chance of them breeding.
"Second of all, they are going to be in field cages. The people who
are going to do this work have years of experience working with
these field cages.
"They know what is involved in maintaining them and the only way
an enclosed population is going to get loose is if a hurricane comes
through and rips the field cages to shreds. There hasn't been a
hurricane in Arizona in these areas in living memory.
"One thing we do know: the native population is a champion at
survival. It has so far resisted any attempts to eradicate it except in
central California.
"Our ultimate plans are to insert conditional lethal genes that will
fight against this enormously successful tendency to survive and
infest cotton."
Approval pending
US regulators have yet to give the greenlight to the release but
Professor Miller says he is optimistic the field trials, planned for the
summer, will be given the go-ahead in the next few weeks.
The pink bollworm, a major pest of commercial cotton in the
southwest, is not native to the US but hitched a ride there in the
1920s, probably in cotton shipments from India.
The larvae are tiny white caterpillars with dark brown heads that
burrow into cotton bolls causing devastation to the crop. They grow
into greyish-brown moths.
The engineered moths contain a
genetic marker, a green
fluorescent protein (GFP) derived
from the jellyfish, which makes
caterpillars inheriting the gene
glow green under fluorescent
light.
In the first stage of the
experiment, the scientists plan to
release the moths under a
seven-metre (24-foot) long cage
in a small test site remote from
commercial cotton fields.
Although the laboratory insects
are confined to a cage, they will
be able to mate with native
insects already present on the cotton at the time of the release,
allowing the scientists to track the spread of the gene through the
population.
Insect control
The field trials could pave the way for the first attempt to eradicate
insects from the wild by releasing genetically modified laboratory
strains. By inserting an inherited lethal trait into the moth the
scientists believe they might be able to "get rid of the pink
bollworm" from the US altogether.
Similar research is focusing on the disease-carrying mosquito.
Researchers from the US and Taiwan have modified the yellow fever
mosquito to make it produce a powerful antibacterial protein, limiting
its ability to transmit disease.
If such insects were ever released in the wild, they might supplant
infected natural populations, helping in the fight against human
disease.
Besides insects, a number of
other transgenic animals are on
the way. The US Food and Drug
Administration (FDA) is currently
deciding whether to allow a
fast-growing genetically modified
salmon on to American dinner
plates. Scientists believe
genetically modified carp may
already be in commercial use in
China while genetically modified
tilapia may be in use in Cuba.
Other examples of aquatic GMOs
include transgenic channel catfish,
modified Pacific oysters and
hybrid striped bass.