Now, two unrelated groups of researchers say they have developed new ways to fight the spread of malaria by genetically modifying the mosquitos that spread the deadly parasite. One solution prevents mosquitos from being infected with malaria and the other makes infected mosquitos infertile.
Malaria is easily one of the most deadly diseases in the world, killing 500,000 people and sickening hundreds of millions more every year, according to the World Health Organization. While there are medications to treat malaria, the best way to prevent it is to stave off mosquito bites.
In recent years, however, researchers started experimenting with ways to prevent malaria transmission at the source, using a new gene-editing technique called CRISPR, which allows scientists to edit genetic sequences rapidly and precisely.
Researchers at the University of California just published one possible solution: Insert a modified gene into mosquitoes that makes them incapable of carrying the malaria parasite, Maggie Fox reports for NBC News.
"This opens up the real promise that this technique can be adapted for eliminating malaria," study co-author Anthony James tells Fox. "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."
Not only did the mosquitoes in the study become malaria-resistant, but they were able to pass the gene to 99.5 percent of their offspring. That means that within a few generations, they could spread the gene to wild mosquitoes, effectively creating a natural barrier to malarial infection, Fox writes.
Meanwhile, scientists at the Imperial College London were working on a similar CRISPR project. But while the scientists at the University of California were trying to alter the mosquitos, this team wanted to wipe them out, Michelle Roberts reports for the BBC.
Led by molecular biologist Tony Nolan and vector biologist Andrea Crisanti, the mosquitoes created by London-based researchers could still carry and transmit the parasite. But they were infertile, according to their study published in Nature Biotechnology.
If the bugs were allowed to interbreed with wild mosquitoes, the species could eventually be driven into extinction, Fox writes. While some experts are worried that wiping out one species of mosquitoes could harm the environment, Nolan argues that the species his team is experimenting with is just one of 800 in all of Africa and eliminating it wouldn’t upset the balance of nature.
While it will be decades before anyone might consider releasing any of these mosquitoes into the wild, these studies raise some intriguing questions about CRISPR’s potential.