July 28, 2005 12:20 PM PDT
Are scientists playing God with Frankentrout?
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The modified fish are bigger because they have three sets of chromosomes, rather than two sets, as is normal. Rainbow trout with the extra chromosomes--the long strands of DNA that determine genetic makeup--grow faster because they are unable to reproduce. The energy from the food they eat is shifted from reproduction to growth, said William Hershberger at the agency's Center for Cool and Cold Water Aquaculture.
Additionally, the flesh of these modified fish, which are called triploids, doesn't become soft with age, and their skin doesn't become dark--common traits in normal fish. The trout's prominent hook nose doesn't develop so rapidly either. While these characteristics aren't problems for the trout, consumers tend to shy away from ugly fish, Hershberger said. Ugly, unsold fish, of course, means wasted food and lower profits.
Under a strategy used by some fish hatcheries, embryos are exposed to heat or pressure about 20 minutes after fertilization to add the third set of chromosomes.
But under the technique created at the Agricultural Research Service, scientists apply heat or shock to actually add two extra sets of chromosomes, creating a tetraploid. When they grow, the four-chromosome-set fish breed with normal fish and give birth to a three-chromosome-set generation. The addition of the two extra chromosome sets can occur up to five hours after fertilization.
A three-chromosome-set trout grown in a hatchery will weigh 10 to 12 pounds after two years, he said, while a normal, two-chromosome-set fish from a hatchery will weigh 8 to 10 pounds. In the wild, a trout might make it to 5 pounds.
The technique promises a couple of advantages. One, all of the fish bred in the new generation will have three sets of chromosomes. Only about 70 percent of the fish created using the earlier technique ended up with three sets. The fish produced from the breeding of tetraploids with diploids also grow faster.
Genetic engineering remains highly controversial. Opponents say it creates hazards for the ecosystem and that tomatoes and other genetically modified foods don't taste nearly as good as natural ones. Proponents assert that genetic modification, in the form of selective breeding, has been around since the dawn of agriculture at the end of the last ice age. Genetic modification also curbs pesticide consumption and increases yields.
Hershberger added that trout with three sets of chromosomes do not present a danger to the ecosystem if they get out of the lab because they are sterile. Thus, they can't breed with wild stocks.
However, the lab and breeders will have to take careful measures to make sure none of the four-chromosome-set fish get out.
"The tetraploids would breed with the duploids and create sterile triploids," he said.
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been around since the dawn of agriculture"
No. Never before have genes from totally unrelated species (i.
fish and tomato) been forced to recombine, or embryos been
exposed to heat or pressure about 20 minutes after fertilization.
Not by God, not by nature.
"Genetic modification also curbs pesticide consumption and
increases yields."
Organic farming methods reduce pesticide usage to zero, and
healthy soils increase yields.
Genetic modification = short term gains to corporate coffers,
long term damage to man and his environment.
been around since the dawn of agriculture"
No. Never before have genes from totally unrelated species (i.
fish and tomato) been forced to recombine, or embryos been
exposed to heat or pressure about 20 minutes after fertilization.
Not by God, not by nature.
"Genetic modification also curbs pesticide consumption and
increases yields."
Organic farming methods reduce pesticide usage to zero, and
healthy soils increase yields.
Genetic modification = short term gains to corporate coffers,
long term damage to man and his environment.
What's next, chicken with no heads?
I am glad Europe has been opossing GM foods in a while. I hope they never allow that trash to come in.
I live in the US, and fresh food in here is terrible. Waxed, GM'ed, with no taste. And organic food is considered luxury, so it cost$ too much.
Even my country, Albania has much better access to fresher and healthier food.
What's next, chicken with no heads?
I am glad Europe has been opossing GM foods in a while. I hope they never allow that trash to come in.
I live in the US, and fresh food in here is terrible. Waxed, GM'ed, with no taste. And organic food is considered luxury, so it cost$ too much.
Even my country, Albania has much better access to fresher and healthier food.
Also, if by some mischance a few of the modified trout escape there will not be any effect on the wild populations. Triploids are sterile so all they do in the wild is compete for food and if a tetraploid escapes, it might mate, but all of its offspring will be triploids which (again) are sterile.
Big waste of time and effort as nobody is going to purchase a genetically modified fish that is larger with the same characteristics.
If you like to eat trout you'll go fishing and will never ever get that experience or taste from your local grocery store.
Also, if by some mischance a few of the modified trout escape there will not be any effect on the wild populations. Triploids are sterile so all they do in the wild is compete for food and if a tetraploid escapes, it might mate, but all of its offspring will be triploids which (again) are sterile.
Big waste of time and effort as nobody is going to purchase a genetically modified fish that is larger with the same characteristics.
If you like to eat trout you'll go fishing and will never ever get that experience or taste from your local grocery store.
Our children's children's children will wake up to a harmless little engineered food productivity experiment gone bad. Beautiful trout living in the streams and lakes for thousands of years are introduced to a few hundred, thousand or hundred thousand sterile trout. Trying to breed the real trout mate with sterile trout. Again and again. The result...no trout eggs, hatchlings and soon no trout.
Buy hey, we're better looking than those real guys...till we become extinct.
Our children's children's children will wake up to a harmless little engineered food productivity experiment gone bad. Beautiful trout living in the streams and lakes for thousands of years are introduced to a few hundred, thousand or hundred thousand sterile trout. Trying to breed the real trout mate with sterile trout. Again and again. The result...no trout eggs, hatchlings and soon no trout.
Buy hey, we're better looking than those real guys...till we become extinct.
If you grew up in a murky pond and were fed a diet of what looks and tastes like compressed dog food pellets, you'd be dark and ugly to.
The trout you see in every grocery store are nasty. I tried one once and will never purchase another. If you've not got enough energy to grab rod and reel and go fishing for fresh trout the experience of eating them should be skipped.
Another big problem is most trout nowdays are stocked into streams from those murky ponds usually around two weeks before the fishing season opens. This renders most of them just as nasty as those purchased at the grocery.
Bottom line is you can't purchase a good trout and you really have to get off the beaten path to catch one.
If you grew up in a murky pond and were fed a diet of what looks and tastes like compressed dog food pellets, you'd be dark and ugly to.
The trout you see in every grocery store are nasty. I tried one once and will never purchase another. If you've not got enough energy to grab rod and reel and go fishing for fresh trout the experience of eating them should be skipped.
Another big problem is most trout nowdays are stocked into streams from those murky ponds usually around two weeks before the fishing season opens. This renders most of them just as nasty as those purchased at the grocery.
Bottom line is you can't purchase a good trout and you really have to get off the beaten path to catch one.
The trout pictured in this article is either pond raised or a brown trout.
Trout raised in ponds loose all their color and flavor.
<a class="jive-link-external" href="http://www.flyfishalberta.com/trout/rainbow.htm" target="_newWindow">http://www.flyfishalberta.com/trout/rainbow.htm</a>
The trout pictured in this article is either pond raised or a brown trout.
Trout raised in ponds loose all their color and flavor.
<a class="jive-link-external" href="http://www.flyfishalberta.com/trout/rainbow.htm" target="_newWindow">http://www.flyfishalberta.com/trout/rainbow.htm</a>
go into your local gardening store. all those roses, orchids, tomatoes, whatnot, are all genetically modified. what, you think granny apples, delicious red apples, and green apples all existed when the dinosaurs were walking around?
many plants can cross pollinate, for example, pumpkins and squash. that's genetic modification. what, are you going to propose we stop all the bees from pollinating them?
do you think your pet golden retreiver was running around with the dinos too? ALL domesticated animals are genetically modified. you think all your varieties of dogs and cats have always been around? even the purebred breeds have been genetically modified. are they harmful to our environment? are they endangering our health and the health of our offspring?
mules are the genetic combo of a donkey and a horse. they're sterile, by the way. OMG, that's so unnatural and harmful to our environment, just like the sterile triploid trout!
to the poster of the first comment, PLEASE APPLY THOUGHT. and common sense. try reading a book sometimes. try to educate yourself. nowhere in the article did it mention combining a fish and a tomato. but yes, genes CAN and HAVE been combined between different species as in the examples i just gave. and what's this about embryos being exposed to heat as "Not by God, not by nature?" HAHAHA. embryos NEED heat. was your mother in a freezer the whole time she was pregnant? why do you think eggs are INCUBATED? they need warmth, heat. now what the fish hatcheries probably do is apply MORE heat than usual to cause the genetic mutation. but even this is not unnatural. you think a hot sun can't provide extra heat to eggs spawned in shallow water? you think genetic mutations never occur in nature? tell that to the next kid you meet with down's syndrome. people so misinformed and uneducated like you should not be making decisions about social issues.
am i antagonizing myself with these harsh words? yes, most likely. but i just can't stand it when people spew this kind of crap. OMG, genetically modified foods are bad! scientists are playing god! hint: everything around you is genetically modified (unless everything just pre-existed during the inception of the earth). YOU are genetically modified (unless your family tree doesn't branch). farmers have been genetically modifying forever. you don't have to accept it (you should), but you need to at least acknowledge it.
go into your local gardening store. all those roses, orchids, tomatoes, whatnot, are all genetically modified. what, you think granny apples, delicious red apples, and green apples all existed when the dinosaurs were walking around?
many plants can cross pollinate, for example, pumpkins and squash. that's genetic modification. what, are you going to propose we stop all the bees from pollinating them?
do you think your pet golden retreiver was running around with the dinos too? ALL domesticated animals are genetically modified. you think all your varieties of dogs and cats have always been around? even the purebred breeds have been genetically modified. are they harmful to our environment? are they endangering our health and the health of our offspring?
mules are the genetic combo of a donkey and a horse. they're sterile, by the way. OMG, that's so unnatural and harmful to our environment, just like the sterile triploid trout!
to the poster of the first comment, PLEASE APPLY THOUGHT. and common sense. try reading a book sometimes. try to educate yourself. nowhere in the article did it mention combining a fish and a tomato. but yes, genes CAN and HAVE been combined between different species as in the examples i just gave. and what's this about embryos being exposed to heat as "Not by God, not by nature?" HAHAHA. embryos NEED heat. was your mother in a freezer the whole time she was pregnant? why do you think eggs are INCUBATED? they need warmth, heat. now what the fish hatcheries probably do is apply MORE heat than usual to cause the genetic mutation. but even this is not unnatural. you think a hot sun can't provide extra heat to eggs spawned in shallow water? you think genetic mutations never occur in nature? tell that to the next kid you meet with down's syndrome. people so misinformed and uneducated like you should not be making decisions about social issues.
am i antagonizing myself with these harsh words? yes, most likely. but i just can't stand it when people spew this kind of crap. OMG, genetically modified foods are bad! scientists are playing god! hint: everything around you is genetically modified (unless everything just pre-existed during the inception of the earth). YOU are genetically modified (unless your family tree doesn't branch). farmers have been genetically modifying forever. you don't have to accept it (you should), but you need to at least acknowledge it.
of yours and release that s*** for brains that you have. Leave the fish alone!!
of yours and release that s*** for brains that you have. Leave the fish alone!!