For the first time, researchers have genetically modified mosquitoes to make them sterile. And stop the spread of malaria.
In a study published this Monday in the journal Nature Biotechnology, British scientists say they have reached an important milestone in the fight against malaria. How? ‘Or’ What ? By creating a genetically modified mutant mosquito that they made infertile.
The stated objective of this team is ambitious since it is simply a question of eliminating Anopheles gambiae. It is precisely the insects that spread malaria to people through their bites.
The researchers explain that two copies of a mutant gene are needed to make the female insect completely sterile. But a single copy of this gene could be enough for it to spread in a population. Ultimately, these mosquitoes should ultimately carry two genes and be completely sterile.
In experiments carried out in England, pairs of mutant mosquitoes transmitted the gene for infertility to more than 90% of their offspring. This is thanks to the technique called “gene drive”. It makes it possible to delete a specific DNA sequence by replacing it with another, thus making it possible to substitute the allele from one gene to another.
The main authors of the study, Dr Tony Nolan and Prof. Andrea Crisant, even claim to have successfully passed on this sterility gene over five generations.
Fears of upheavals in the ecosystem
During this work, some British experts had indicated that they feared that by completely erasing these mosquitoes from the surface of the globe, the natural balance of the environment would be upset. Professor Tony Nolan now claims that the method developed “will not cause effects in the general mosquito population, but only on those who transmit malaria”.
And the latter concludes: “There are about 3,400 different species of mosquitoes around the world. And Anopheles gambiae which is an important vector of malaria represents only some 800 species of mosquitoes established in Africa, eliminating it in certain territories should not therefore significantly affect the local ecosystem, ”he says.
Mutant mosquitoes released in 10 years
Clearly, the aim of the experiment is therefore to perpetually propagate this infertility gene so that the mosquito species concerned becomes extinct for good.
The team at Imperial College London is warning, however, saying that security tests are still needed. This means that it will take at least a decade before these mutant mosquitoes are released into the wild, and do their work …
Malaria infects more than 200 million people each year and causes more than 430,000 deaths worldwide.
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