Science

Transgenic trout given body-builder physique with six-pack abs

Transgenic trout given body-bu...
What are you lookin' at? The transgenic trout flexes its six-pack
What are you lookin' at? The transgenic trout flexes its six-pack
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The transgenic trout
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The transgenic trout
What are you lookin' at? The transgenic trout flexes its six-pack
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What are you lookin' at? The transgenic trout flexes its six-pack
The transgenic trout
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The transgenic trout
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Researchers have developed transgenic rainbow trout with enhanced muscle growth that results in fish with what have been described as six-pack abs and muscular shoulders. Aside from ensuring the muscular trout don't get bullied by other fish, the development could provide a boost to the commercial aquaculture industry.

The transgenic trout are the result of a ten-year effort by University of Rhode Island (URI) professor of fisheries and aquaculture, Terry Bradley, who researched the effect of inhibiting myostatin in the fish. Myostatin is a protein that is produced primarily in skeletal muscle cells, circulates in the blood and acts on muscle tissue to slow muscle growth.

According to Bradley, the number of muscle fibers in mammals is limited after birth, but in fish, muscle fiber numbers increase throughout their lifespan. Since inhibition of myostatin increases the numbers of muscle fibers, it had been a mystery as to whether inhibiting myostatin would cause an increase in muscle growth in fish.

"Belgian blue cattle have a natural mutation in myostatin causing a 20-25 percent increase in muscle mass, and mice over-expressing myostatin exhibit a two-fold increase in skeletal muscle mass. But fish have a very different mechanism of muscle growth than mammals, so we weren't certain it was going to work," Bradley said.

But work it did with the transgenic trout growing 15-20 percent more muscle mass than standard fish. To achieve this, Bradley and a team of graduate students spent 500 hours injecting 20,000 rainbow trout eggs with various DNA types designed to inhibit myostatin.

Of the eggs that hatched, 300 carried the gene that led to increased muscle growth. After two years, most exhibited a "six-pack ab" effect, even though fish lack standard abdominal muscles. They also had increased musculature throughout, including a prominent dorsal hump that made them look like they had muscular shoulders.

The first generation of transgenic trout were subsequently spawned, and offspring carrying the gene in all of their muscle cells have been produced. Studies are underway to determine if the fish grow at a faster rate, as well.

"Our findings are quite stunning," said Bradley, who also studies salmon, flounder and tuna. "The results have significant implications for commercial aquaculture and provide completely novel information on the mechanisms of fish growth. The results also allow for comparisons between the mechanisms of growth of muscle in mammals versus fish, and it could shed light on muscle-wasting diseases in humans."

About 500,000 metric tons of rainbow trout are raised each year in aquaculture facilities in the US and Europe. In the US, some 1,000 trout farms produce approximately US$80 million of trout annually, mostly in Idaho, New York, Pennsylvania and California. Assuming Bradley's transgenic fish meet with regulatory approval, it could provide a boost to the industry by enabling aquaculturists to grow larger fish without increasing the amount of food the fish are fed.

"One of the advantages of this approach is that the modified genes introduced into the fish use the same mechanism and cause the same type of effect that occurs naturally in Belgian blue cattle and other 'double muscled' animals," said Bradley.

While the transgenic trout may look like bodybuilders, Bradley said they exhibit normal behaviors. He will continue to study the fish to learn if the new gene affects any other genes, and to determine if new husbandry practices will aid in the raising of the trout.

Personally, I hope these muscle-bound trout don't escape confinement. Getting sand kicked in my face by Herculean humans at the beach is bad enough – getting beaten up by a shoal of burly trout would be one humiliation too many.

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32 comments
masimons
Who the heck would want to eat that ? Short of Ricardo Montalban (star trek ref). Stop the rsch, esp if gov\'t funded, and kill all those fish before they get loose.
Nick Gencarelle
There is nothing scarier than this out there right now for fisheries-imaging the damage such a fish could wreak on the whole ecosystem if someone put it into the wild and they would! This should be banned way more than embryo testing, way more than any stem cell research or genetically altered crops. It is wrong and should be stopped immediately. I doubt they can make these male sterile.
Lafferty1947
We could save a lot of money for the school and taxpayers by firing morons that come up with these ideas! I would never eat any fish like this!
Facebook User
Killer Bees come to mind!
Raum Bances
The concept is just disgusting. We really need to stop mucking around and genetically modifying food.
They think this will improve sales but it will have the opposite affect. Once other countries find out we are putting fish with bastardized DNA in with other fish, they will stop buying any of it. If you don\'t believe me, look into Monsanto and see what is going on right now with GE vegetables. (GMO food)
They are ruining things for everyone and worse still, run the risk of damaging the original DNA pool of the species by polluting it with this crap.
Ravenacious
I think that fears of this type of fish somehow escaping and wreaking havoc on the ecosystem are probably unfounded. There is almost always a down-side to being some kind of super animal. Rainbow trout have been about for some millions of years and, in that time, if the particular mutation that these fish have was advantageous in the wild, then it would have probably come about naturally. My guess would be that these fish need more food than a regular fish. They probably aren\'t as effective at surviving periods of starvation either, with their body constantly trying to manufacture more muscle mass. These kinds of consideration mean that this kind of fish would get on great in an environment where food is abundant (like in a fishery, with a farmer throwing food at them as fast as they can eat it), but much more poorly when food might not be so abundant. My guess would be that they would be rapidly out-competed by the wild trout.
On some level, it is arrogant of us a species to think that we could take something that has been hewn by nature over millions of years and improve it into some kind of super-being by making some simple changes.
On the eating front, meat is meat. There is no difference in eating meat from these fish to a normal trout.
Fisher
Just a little fisheries/scientific facts FYI. One, that fish is obviously in spawning season, which explains the coloration. Stores don\'t sell spawning fish because of there apperance. Give that fish 6 months and it would be chrome. Second there are no natural populations of RBT in RI (they are stocked annually from hatcheries) and transgenic fish are already maintained in secure facilities. Third, transgenic fish can easily be sterilized by triploidy or other methods which are commonly performed. Fourth, that muscled look will likely only be present in the fish that had the DNA injected into them. It is a common side effect of making transgenic organisms that not all of the cell will contain the DNA in the parents. That fishes babies will look normal, just bigger, and those would be the fish you would eat. And finally, what the article doesn\'t describe is the significance of work like this to our understanding of the physiology of animals. It is just one step further to understanding what makes life work. I say the more informed we are about the world around us the better off we will be.
Ed
@Raum Bances There is nothing wrong with genetically modified food. In fact, everything you eat has been genetically modified! Even if you grow your own vegetables. Without genetically modified foods, half the worlds population would starve to death! Every piece of bread you eat, every apple you eat, every ear of corn you eat..is a hybrid...in other words, genetically modified! in fact, the original color of carrots is not orange. They are black/purple. They were genetically manipulated back in the 17th century for purely political reasons in order to appease the English Earl of Orange! http://www.nextnature.net/2009/08/why-are-carrots-orange-it-is-political/
And we can go back thousands of years for wheat! This crop has been so genetically modified, we don\'t even know what it\'s original genome was!
So, when you say you are against GMO foods, you are basically saying you want half the population of the planet earth to die. Because that is what would happen if we didn\'t genetically modify things to fit our every burgeoning population! Ed
heldmyw
Yeah, yeah. The REAL issue is: are the filets better when they\'re dusted with corn meal and fried in bacon fat, or grilled over coals and doused with a yummy, buttery amandine sauce?
I\'ve eaten uglier things than that, and so have you!
Darren Johnson
To the authors of the first 5 comments: if technology and its applications scare you so much, then why on earth are you even using a computer?