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Giant Genetically-Altered Salmon Set To Enter
Unregulated US Market
Published on Monday, May 1, 2000 in the New York
Times
By Carol Kaesuk Yoon
With quaint
fishing villages dotting its shores and farming
still one of its mainstays, the pastoral
landscape of Prince Edward Island seems an
unlikely place to encounter one of the most
modern creatures on earth. Yet it is in the
tanks at Aqua Bounty Farms on the island off New
Brunswick, Canada, that hundreds of truly novel
fish swim: schools of genetically engineered
salmon that await approval for sale in the
United States.
These fish look like Atlantic salmon found in
groceries around the world, but for their age
they are enormous. Endowed with foreign genes
that produce growth hormones, they grow to
market size -- about seven pounds -- in 18
months, twice as fast as normal salmon.
Experts on the biotechnology industry predict
that these fish will be the first genetically
modified animal to make it onto American dinner
plates, alongside genetically engineered
vegetables like corn and potatoes, which have
been available for several years.
Elliot Entis, president of A/F Protein Inc., the
biotech company that owns Aqua Bounty Farms,
said that the company already had orders for 15
million eggs and would be ready to ship them
next year, should they receive federal approval.
Approval is also being sought to sell the fish
in Canada.
A menagerie of other genetically modified
animals is in the works, promising what biotech
backers say will be advantages like cheaper and
more nutritious food. Borrowing genes from
various creatures and implanting them in others,
scientists are creating fast-growing trout and
catfish, oysters that can withstand viruses, and
an "Enviropig," whose feces are less harmful to
the environment because they contain less
phosphorus.
Scientists are also developing a pig that makes
a leaner pork chop, one of the first genetically
modified animals that would offer direct
benefits to consumers and something biotech
advocates hope will make the marketing of
genetically modified foods easier.
Mr. Entis and colleagues describe their
fast-growing fish as part of a blue revolution
in aquaculture that could feed more people more
efficiently and more cheaply.
But critics and even some Clinton administration
officials say that genetically engineered
creatures are threatening to slip through a net
of federal regulations that has surprisingly
large holes.
While food safety issues should be addressed,
some scientists say, the bigger concern is the
environmental threats posed by genetically
modified animals like the salmon. For example, a
recent study showed that populations of wild
fish could, in theory, be wiped out by mating
with certain kinds of genetically engineered
fish, should they escape. In addition, there is
the possibility of unpredictable environmental
disruptions, like those that occur when
non-native species invade ecosystems, as the
zebra mussels have the Hudson River.
Yet United States regulators interviewed could
not point to any federal laws specifically
governing the use or release of genetically
engineered animals.
"This is a very big hole," said Dr. Rebecca
Goldburg, senior scientist at the Environmental
Defense Fund, a group that has been highly
critical of the biotech industry and the federal
regulators. "There's nothing clearly on the
books. There are no regulations about what you
can and can't do."
Instead, federal agencies seeking to regulate
genetically engineered organisms are stretching
regulations written for other purposes to what
critics describe as surprising lengths.
So far, for example, only the Food and Drug
Administration appears to have any authority
over the new salmon, which the agency claimed by
designating the fish's foreign genes and the
growth hormone they produce as a drug for
animals.
The Environmental Protection Agency and the
Department of Agriculture, the two other
agencies overseeing genetically modified
organisms, have bowed out of the salmon case, a
decision that many with an interest in the issue
regret. The F.D.A. is likely to be rigorous in
examining food safety, these critics say, but
the agency is less experienced in reviewing
environmental risks.
"The F.D.A. is not qualified to evaluate the
ecological risks of engineered fish," said Dr.
Jane Rissler, senior staff scientist at the
Union of Concerned Scientists, a watchdog group
that is a longtime critic of biotech regulation.
"We should be concerned that the environment
will be at risk."
John Matheson, senior regulatory review
scientist at the Food and Drug Administration's
Center for Veterinary Medicine, defended the
agency's ability to conduct environmental
reviews, saying that it routinely investigates
the environmental impact of new drugs.
"We look at the environmental impacts of
approving an antibiotic, how much is released
into the environment, what does it do," Mr.
Matheson said. "I don't have any more discomfort
about this than reviewing other animal drugs for
environmental impacts."
Yet other administration officials said
increasing concern over the handling of
ecological risks by the three federal agencies
that monitor biotech organisms had prompted
consideration of a review of the current
regulatory framework.
"We need a system that lets us check things
beforehand, that shifts the burden of proof onto
those that would introduce them," said Dr.
William Brown, science adviser to the secretary
of the Department of the Interior. "I don't
think the potential impacts on nature have been
thought through as well as they should be."
FOOD SAFETY
Agency Cites Low Levels of Growth Hormone
Dr. Choy Hew and Dr. Garth Fletcher were among
the first researchers to genetically engineer
fish when they inserted two foreign genes into
Atlantic salmon in 1989. One gene, taken from a
chinook salmon, produces growth hormone. A
second gene, taken from an ocean pout, a distant
relative of salmon, functions to keep the first
gene constantly producing its hormone.
Finally, last year, after a decade of genetic
tinkering, researchers had a reliable breeding
stock of salmon that could grow up to six times
faster than normal.
Company officials are quick to point out that
the new fish produces no more growth hormone
than normal salmon. The reason the fish grows
faster, Dr. Fletcher said, is that the fish
produces the hormone year-round, unlike normal
salmon, which produce it only in warm-weather
months.
In fact, levels of growth hormone in the fish
are so low, Mr. Matheson said, that the Food and
Drug Administration will not require one
particular set of tests -- feeding the salmon to
rodents -- that are typical for new drugs for
animals.
"You can't choke rats with enough salmon to
cause an effect other than choking," he said.
Some scientists not involved with the company
also pointed out that fish growth hormone was
unlikely to have an effect on humans.
The salmon do not even grow to be unusually
large, Dr. Fletcher said, as even 7-year-old
salmon at AquAdvantage have never weighed more
than 17 pounds, large but far from
record-breaking for the species.
Mr. Entis also said that the new fish taste just
like other salmon grown on farms.
Some scientists not involved with the company
also played down food safety concerns but said
it would be important to know, for example, if
the foreign growth hormone triggered increased
production of other compounds, like insulinlike
growth factors. Mr. Entis of A/F Protein said
the company had been asked to look into that
question and others as part of the continuing
Food and Drug Administration review.
ENVIRONMENTAL SAFETY
Studies Are Done on Hypothetical Situations
Salmon are typically grown in enclosures in the
sea, known as net pens, renowned for being torn
by waves or hungry wild animals. Fish routinely
escape, sometimes by the tens of thousands.
If the genetically engineered, or transgenic
fish, are grown in such pens, some will
eventually slip out into the wild, some
researchers say.
If they do, wild fish could be potentially
devastated, according to a study published in
the journal Proceedings of the National Academy
of Sciences in November by Dr. William Muir, a
population geneticist, and Dr. Richard Howard,
an aquatic ecologist, both at Purdue University.
The two researchers studied mating and
survivorship in normal and genetically
engineered versions of a fish known as a medaka.
Using this information, researchers developed a
computer model simulating the escape of a
genetically modified fish into the wild. The
study showed that if wild females preferred to
mate with genetically engineered males and if
those matings produced offspring that did not
survive well, wild populations could be wiped
out, a result they called the Trojan gene
effect.
Those, of course, are a couple of big ifs -- no
studies have shown whether any fish could create
the Trojan gene effect in the real world. But
there is evidence of its potential. In many
species of fish, females prefer larger males as
mates, setting the scene for an advantage for
growth-enhanced fish.
In addition, Dr. Muir said the genetically
engineered fish he is now studying, the tilapia,
could be three times larger than normal tilapia
at sexual maturity, providing a possible mating
advantage. In addition, in some new fish,
including the medaka and coho salmon endowed
with foreign growth hormone genes, rapid growth
can be harmful, lowering the fish's survival
rate.
Whether all these pieces would come into play in
the wild, in the AquAdvantage fish or any other,
remains to be seen. But even the possibility has
jolted some researchers.
"It really surprised me," said Dr. Muir, who has
been developing transgenic fish that he hopes to
sell. "I went into this thinking that
transgenics are not a risk."
Dr. Muir said that while in theory the Trojan
gene effect could occur with traditionally bred
salmon as well, he believed it was essentially
impossible. Traditional breeding tends to result
in incremental changes, not the kind of rapid
growth that produces radically different size
fish or that causes physiological disruptions
that are likely to alter a fish's survivorship.
At A/F Protein, Mr. Entis said that he and
colleagues did not believe their AquAdvantage
salmon could cause a Trojan gene effect. "We
don't think that they are bigger," he said.
"They don't seem any bigger."
But he acknowledged that the company had not
done the critical experiments to determine
whether the fish were larger at sexual maturity
or had a mating advantage.
he power of genetic engineering is providing
scientists with the ability to create animals
that confound the imagination.
The most striking of the new creatures being
concocted by plucking a gene from one organism
and inserting it into the DNA of another are
what are known as pharm animals. These
domesticated beasts -- cows, pigs, goats, sheep
and chickens -- have been given the ability to
produce pharmaceuticals and other valuable
substances in their milk, eggs or semen.
Endowed by scientists with foreign genes, often
taken from humans, these animals, or
bioreactors, as they are also known, earn their
keep as living chemical factories.
Two companies, the Genzyme Corporation of
Cambridge, Mass., and PPL Therapeutics, a
Scottish company, already have products from
pharm animals being tested in clinical trials
supervised by the Food and Drug Administration.
Many other animals are still in the development
stage. For example, Nexia Biotechnologies in
Canada is working on a goat that carries a gene
from spiders allowing it to produce spider silk
in its milk. When the spider silk, which
consists of extremely strong, light proteins, is
extracted from the goat's milk, the substance,
potentially, can be used in applications like
bulletproof vests.
Scientific competition is fierce. Some compounds
of interest, like the human blood protein
erythropoietin, which has not yet been produced
by a pharm animal, command prices of more than
$15 million an ounce.
"There is no limit to what can be done," said
Dr. Francois Pothier, reproductive biologist at
the University of Laval in Canada, who is
working on a pig that is genetically engineered
to produce a drug. Dr. Pothier declined to name
the substance.
But because research required to create these
animals can take years, the drugs they produce,
he said, have to be "very interesting and very
expensive." Dr. Pothier said his pigs would
produce a drug in their semen, which the pigs
could be trained to donate regularly in
voluminous quantities.
Dr. Ann Gibbins, molecular geneticist at the
University of Guelph, in Canada, and her team
are trying to create chickens that make
antibiotics in their eggs.
Researchers say pharm animals are the only way
to produce some of the more complex proteins
needed for use as drugs. Some very simple
proteins, like insulin, can be churned out by
genetically modified bacteria. But some proteins
require being folded in particular ways or
having sugars added before they can be used.
Bacterial cells cannot carry out these advanced
tasks but animal cells can, making pharm animals
the producers of choice.
Pharm animals are also of interest because some
therapeutic proteins otherwise have to be
collected from blood donated by people, which
can be tainted by viruses.
Because they are domesticated and are so
valuable, pharm animals are extremely unlikely
to escape or pose any environmental threat. But
they may still pose risks. Animal tissues and
fluids can contain other disease-causing
contaminants, like prions, a poorly understood
class of molecules associated with maladies
including mad cow disease.
In addition, while animal rights groups have
remained relatively quiet on the issue of
genetically engineered animals, some say that
the use of animals as living factories raises
troubling ethical issues.
There are also food safety issues.
"Those goats are not going to just get a decent
burial after they grow old and stop producing
silk," said John Matheson, senior regulatory
review scientist at the Center for Veterinary
Medicine at the Food and Drug Administration,
"so we have to look at them as potential food
and as potential feed ingredients."
In fact, Mr. Matheson said some genetically
engineered animals had already been approved for
use in animal feeds. He said he was unable to
disclose what kinds of animals had been approved
for such use or what animals they might be fed
to as these genetically engineered animals are
still experimental and under confidential review
within the Food and Drug Administration.
But to prevent the spread of prion-associated
maladies, Mr. Matheson said, cows would not be
given feed made from cows, genetically
engineered or not. Noting that animal feed often
contains ingredients like rotting animals killed
on highways and parts of slaughtered animals,
Mr. Matheson said, "Transgenics should be the
least of your worries, frankly."
Mr. Entis said the Food and Drug Administration
had not specified what studies, if any, would be
required that directly addressed such ecological
risks. So far the company has done none.
"Lord knows we can't promise total safety for
anything," Mr. Entis said.
But, he said, "We believe that our fish are poor
survivors out there to start with." Normal fish
do not produce growth hormone in the winter,
presumably because it is disadvantageous to do
so. Mr. Entis reasoned that since AquAdvantage
fish produce the hormone year-round, they would
not last long enough in the wild to do any harm.
Dr. Anne Kapuscinski, a fish geneticist at the
University of Minnesota who has studied
potential impacts of the release of genetically
engineered fish, said, "Belief is a great thing,
but what we need is some risk assessment
research."
Similar arguments were once made with
traditionally bred or normal salmon raised on
farms, which were said to be too pampered to
survive in the wild. But escapees have since
been found thriving and spawning in the same
streams as wild salmon.
In fact, environmental groups have long been
concerned that salmon from farms might
genetically pollute wild salmon or carry
diseases into the wild. But little research has
been done and it is still unclear what role, if
any, these escapees are playing in the decline
of wild salmon stocks.
As for the new genetically engineered salmon,
the Trojan gene effect is only one possibility
should the fish escape. The new fish could also
breed with wild fish, genetically polluting
dwindling native stocks of Atlantic salmon.
In response to concerns, Mr. Entis has said the
company would only sell fish that have been
rendered sterile for use in net pens. Then even
if the fish do escape, they cannot breed with
wild salmon.
A/F Protein employs a standard technique for
sterilization that Mr. Entis described as "100
percent effective." But scientists outside the
company said that in other laboratories the
technique often left some eggs fertile.
In addition, some researchers pointed out that
even sterile fish could cause problems by
competing with native salmon or otherwise
disrupting ecosystems.
THE REGULATORS
Marine Agency on the Sidelines
If the three agencies that have so far overseen
the approval of genetically engineered
organisms, only the the Food and Drug
Administration has sought to regulate the new
fish.
Mr. Matheson said the agency had decided to
regulate the new salmon as a drug for animals
after extensive discussions at all levels at the
agency.
Mr. Matheson said it had not been an option to
review the fish as a food since the agency did
not require approval of new foods before they
entered the marketplace. Because the growth
hormone is not used to alter the quality of the
salmon as food, he said, it could not be
regulated as a food additive either. Instead,
the hormone is used to change the growth of the
animal itself, which qualifies it as an animal
drug. In its review of this and other animal
drugs, the agency examines human food safety,
animal welfare and environmental issues.
While Mr. Matheson defended the decision, some
scientists said the handling of the new salmon
put a spotlight on the holes in regulation.
"This kind of stretching of the law places the
emphasis on the wrong things," said Dr.
Kapuscinski of the University of Minnesota,
"Plus, it's ludicrous." She urged "a serious
revisiting" of the regulation now in place.
So far the Food and Drug Administration has not
outlined any explicit policy or process for
regulating genetically engineered fish.
Critics point out that because the salmon is
being regulated as a drug for animals, it is
covered by confidentiality laws that prevent
officials from discussing the review without
permission from A/F Protein. As a result, there
remain many unanswered questions about what
steps will and will not be taken to ensure
environmental safety.
An additional problem, critics say, is that the
Food and Drug Administration is reviewing
environmental risks under the National
Environmental Policy Act, which requires only
that an environmental assessment be done.
Even if the fish should be found to be
environmentally damaging, it can still be
released.
Noting that the Food and Drug Administration's
food safety review is continuing, Mr. Matheson
said the agency was keeping all its options
open, still considering whether A/F Protein
would be allowed to sell fertile fish or only
sterile fish and whether farmers would be
allowed to grow the fish in net pens or only in
tanks on land.
He said the agency would consult with other
agencies in making its decision. But the
agencies typically in charge of fish have yet to
get involved, and it remains unclear what role
they will play.
Dr. Brown, the science adviser to the Interior
Department secretary, said the department might
possess the authority to regulate genetically
engineered animals under statutes for
controlling injurious wildlife and aquatic
nuisances.
If existing authorities should be insufficient,
he added, "Congress might need to get involved."
In an interview in March, Edwin Rhodes,
aquaculture coordinator for the National Marine
Fisheries Service, said he was surprised to hear
that the Food and Drug Administration was
overseeing the environmental review regarding
the new salmon and making decisions on such
things as whether fish would be grown in net
pens. Mr. Rhodes said the National Marine
Fisheries Service, not the Food and Drug
Administration, had the expertise to make such
decisions, and it would need to be involved.
"We have to have absolute certainty that
transgenic fish do not interact with wild
stocks," Mr. Rhodes said.
It remains unclear what role the fisheries
service will play.
Dr. Eric Hallerman, fisheries geneticist at
Virginia Polytechnic Institute and State
University, likened the situation with fish to
that of genetically engineered plants in the
early 1990's when the first crops were being
pushed toward commercial use.
"Environmental safety assessments should be done
before these fish are stocked out on an
industrial scale," Dr. Hallerman said. "It's
time we got our policies together."
THE CONSUMERS
Salmon Producers Eyeing Competitors
Anti-biotech organizations around the world are
already up in arms over the possible dangers to
the food supply and the environment from
genetically modified plants, like corn that
produces its own pesticide, and the use of a
growth hormone in cows. Public concerns over the
new crops have even caused a few prominent
companies to ban their use.
In Scotland and New Zealand, efforts to develop
other salmon using the foreign genes developed
by A/F Protein have been abandoned amid cries of
"Frankenfish."
Likewise, many salmon farming groups, motivated
by a fear of consumer rejection, have already
declared that they will not use genetically
engineered fish, whether governments approve
them or not. So far, none have.
The International Salmon Farmers Association,
which represents the vast majority of salmon
farmers worldwide, has taken a strong stand
against the new fish.
"Genetically engineered salmon is a solution
looking for a problem," said Joseph McGonigle,
executive director of the Maine Aquaculture
Association. "Virtually everyone in the world
has taken a position against them."
But while salmon farmers deny any interest, Mr.
Entis said, "There's not a salmon company in the
world that hasn't talked to us privately."
As adamantly against the new fish as anyone, Odd
Grydeland, a salmon farmer in British Columbia,
said, "If the rest of the world's salmon farming
industry moved to adopt this type of technology
and we were left behind, obviously we'd have to
reconsider our position."
Scientists say genetically modified carp may
already be in commercial use in China and
genetically engineered tilapia may be in use in
Cuba.
"There's going to be more," Dr. Kapuscinski
said. "These fish are just the beginning."
Copyright 2000 The New York Times Company
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