Chickens genetically modified to resist bird flu

It is scientists from the institute where Dolly, the first cloned sheep, was created, who are trying to immunize poultry against the devastating virus. The first results are encouraging but we are still far from the goal.

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Scottish researchers are working on a chicken genetically modified to resist avian flu (illustration).  (LUDOVIC MARIN / AFP)

Researchers at the Roslin Institute at the University of Edinburgh, the research center where the cloned sheep Dolly was created in Scotland, used Crispr technology, “genetic scissors”, to specifically modify a chicken gene . This modification blocks the production by poultry of a protein that the avian flu virus needs to multiply.

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And indeed, when these researchers then exposed these genetically modified chickens to the avian flu virus, 9 out of 10 resisted infection. The icing on the cake is that they are able to pass on this resistance to their descendants. So this is a very encouraging first step.

But we are still far from the goal. Because before we can bet on super-resistant GMO chickens, we will have to ensure that this resistance to the avian flu virus is sufficiently strong and durable over time. And there is doubt, because when these same researchers exposed the genetically modified chickens to much larger doses of avian flu virus, only half of the birds resisted infection.

The modification of a single gene probably insufficient

The virus eventually found a trick to replicate itself using other proteins. This means that modifying a single gene may not be enough. And, moreover, another downside, these genetic modifications in chickens should not push the virus to evolve in a bad direction and become dangerous for humans. Be careful therefore: these resistant chickens are still far from landing in our henhouses.

In the meantime, France is fighting against avian flu through vaccination. To limit the spread of this virus which has killed millions of birds around the world, and which causes heavy economic losses, vaccination has been made compulsory since October 1 in farms with more than 250 ducks. The injection only concerns, at this stage, ducks, the most sensitive to the avian flu virus and its main spreader. 60 million ducks should therefore be vaccinated by summer.


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