Genetically-engineered mosquito 'could help eliminate malaria'
Published 23/11/2015 | 20:09
A mosquito whose immune system has been radically altered using an advanced gene editing technique could set the stage for eliminating malaria, scientists believe.
The insect was genetically engineered to produce antibodies that interfere with the malaria parasite's life cycle and prevent it being transmitted to humans.
Critically, the heritable trait was passed on to 99.5% of the mosquito's offspring, a result described as "astonishing" by the scientists.
Lead researcher Professor Anthony James, from the University of California at Irvine, said: "This opens up the real promise that this technique can be adapted for eliminating malaria.
"This is a significant first step. We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations."
Despite a 60pc reduction in death rates since 2000, the malaria death toll is expected to reach 438,000 this year, according to the World Health Organisation.
The vast majority of victims are in sub-Saharan Africa, which is home to the most dangerous form of the parasite, Plasmodium falciparum.
The new proof-of-concept study focused on the Anopheles stephensi mosquito which accounts for 12% of malaria transmissions in India and carries the P. falciparum strain.
Scientists used a state-of-the-art "cut and paste" gene editing technique called Crispr to insert anti-malaria antibody genes into a highly specific spot in the mosquito's DNA.
The genetic "payload" also had the property of giving offspring glowing red fluorescent eyes. This allowed scientists to see at a glance which of them had the malaria-fighting genes.
They found almost 100pc of offspring inherited the trait, which was unprecedented. Previous attempts at creating anti-disease mosquitoes had only succeeded in about half of progeny being affected.
Further work will be needed to confirm the effectiveness of the antibodies, paving the way to field trials, said the researchers writing in the journal Proceedings of the National Academy of Sciences.
They concluded: "Strains based on this technology could sustain control and elimination as part of the malaria eradication agenda."