The Era of genetically modified animals
Leïla Marchand, Slate.fr: Nous entrons dans l'ère des animaux génétiquement modifies
Translation: ИноСМИ.Ru
Genetically modified plants are now grown on 175 million hectares worldwide (13% of all cultivated areas). They also appear in Europe: since April 2015, the EU has allowed the import and sale of 17 types of GMOs.
Will it be the turn of the animals soon? Although experiments in the field of animal genetic engineering have been conducted since the 1980s, it is still at the research stage. Be that as it may, there are now more and more examples of the concrete application of the acquired knowledge. The last technological barriers that prevented a person from trying any possible combinations of genes are collapsing.
The process is akin to selectionHumans have been changing animal genes for centuries.
"We just called this practice breeding," explains geneticist Mark Westhuzin. If you cross one breed of dog with another for several generations, the result will be a genetic cocktail that nature would hardly mix itself – this is a lapdog.
New genetic tools allow you to make changes more accurately and faster. "We change features in a more pinpoint way: we can tell exactly what we are creating," explains Alison Van Ernam, a genome and biotechnology specialist at the University of California.
The first animal whose genome underwent changes in laboratory conditions was a mouse. In 1982, scientists managed to create a mouse whose body secreted a significant amount of growth hormones. And she reached the size of a small rat.
Treatment with transgenic milkHas the animal grown twice its normal size?
This scientific finding has something to interest agriculture. Salmon twice the size of the norm has already been bred (commercial name AquAdvantage) and may become the first genetically modified fish to be sold for food. The company is only waiting for the go-ahead of the American authorities.
In addition, animals can get immunity from epidemics. For example, British geneticists have bred a chicken that is not afraid of bird flu. In Brazil, genetically modified mosquitoes are used to fight dengue fever.
What is even more interesting, the milk of transgenic animals is fraught with limitless possibilities. Cows have already been changed to obtain maternal and hypoallergenic milk (for those who have lactose intolerance). In the future, it will be possible to get milk with human antibodies to fight melanoma. The American company GTC Biotherapeutics has bred goats whose milk contains antithrombotic substances: called ATryn prevents the occurrence of blood clots.
There are many variants of gene crossing, and some of them are very unusual: after testing on goats, the bacteria were changed to produce a web. This material (considered the most durable in the world) would make it possible to create ultra-efficient bulletproof vests and medical fabrics.
Zebra fish also got the DNA of a glowing jellyfish. The purpose of the experiment: to make them glow in the presence of certain toxins to detect water pollution.
Anyway, GloFish has gained more success in the aquariums of Americans, becoming the first genetically modified pet.
Genetic "scalpels"Scientists are moving further and further in decoding the genome.
It's about understanding how a particular gene determines the characteristics of a species. Progress in genetics has accelerated even more with the discovery of new effective tools, primarily Cas9.
The Cas9 technique was "accidentally" discovered by scientists Emmanuel Charpentier and Jennifer Dudna during experiments on viruses. If you don't go into details, it allows you to find a certain section of DNA and cut it out. When another material is added, it also makes it possible to replace it with another piece of DNA.
According to Jennifer Dudna, all this was a big step forward:
"If in the past technologies were like a blacksmith's hammer, now we are working with the genome with molecular scalpels."
The Rebirth of mammoths and dinosaursWith such technologies in hand, some scientists are going to revive extinct species or even create new ones.
In theory, scientists already understand how it would be possible to bring back to life the woolly mammoth that disappeared 10 thousand years ago: thanks to the tissues and pieces of teeth found in the ice, they managed to almost completely recreate its genome. All that remains is to change the elephant's genes or implant its DNA into the elephant's egg so that a small mammoth is born.
What about dinosaurs? Since the chicken is a descendant of some of them, it's just enough to reverse the process ... Scientists have already done this and were able to reactivate the ancient "dinosaur" genes of the chicken.
Mythical or even absolutely fantastic creatures could come out from under the genetic scalpel. American paleontologist Jack Horner talked about the possibility of creating a unicorn.
Anyway, to breed animals of unusual size (a duck the size of a horse or a horse the size of a duck) seems to be a non-trivial task: growth is determined by hundreds of genes. The same goes for winged pigs. Scientists have not seen vertebrates with six limbs, and have no idea what their genetic code would look like.
How far can you go?But where can such manipulations with the genome lead?
Science fiction in its own way has repeatedly warned mankind about the dangers of such experiments. Remember at least this quote from "Jurassic Park":
"Our scientists were so focused on what they could do that they didn't even think about whether they had the right to do it."
Moving away from bizarre genetic creatures, transgenic animal changes to improve quality and productivity could ensure food security around the world. But what would be the long-term consequences? Environmental and health risks? AquAdvantage salmon has not even appeared on our plates yet, but it already raises concerns about "genetic contamination".
Although no one is able to answer these questions yet, it is high time for us to outline ethical limits: as it became known, Chinese scientists began to change the human genome.
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02.08.2015