Gene tweak kills whole population of malaria-carrying mosquitoes in lab
Scientists have killed a whole population of malaria-carrying mosquitoes in their lab by using modified genes that make the killer insects infertile.
Researchers at London’s Imperial College used “gene drive” technology to spread a genetic modification that blocks female reproduction while letting male mosquitoes continue to spread those altered genes.
The results, published Monday in the journal Nature Biotechnology, represent the first time gene drive has completely suppressed a population, according to an article from Imperial College.
The team crashed populations of the Anopheles gambiae mosquito, which transmits malaria in sub-Saharan Africa, within 11 generations. There are around 3,500 species of mosquito worldwide, of which 40 can carry malaria, the article reported.
In 2016, according to the World Health Organization, there were around 216 million malaria cases and an estimated 445,000 deaths worldwide, mostly of children under five years old.
“This breakthrough shows that gene drive can work, providing hope in the fight against a disease that has plagued mankind for centuries,” Andrea Crisanti, a life sciences professor who led the team, told the college.
“It will still be at least 5-10 years before we consider testing any mosquitoes with gene drive in the wild,” he added, “but now we have some encouraging proof that we’re on the right path.
“Gene drive solutions have the potential one day to expedite malaria eradication by overcoming the barriers of logistics in resource-poor countries.”
The team targeted a gene in the mosquitoes called “doublesex” that determines whether a mosquito develops as a male or as a female, the college reported.
Males that carried the modified gene showed no changes, as did some females; however, many females displayed both male and female characteristics, failed to bite and did not lay eggs.
After about eight generations, no further females were produced and the populations collapsed because of lack of offspring.
The next step will be to test the technology in a laboratory setting that mimics a tropical environment, Crisanti said.
“It will be at least five-to-ten years before we consider testing any mosquitoes with gene drive in the wild,” he added.
According to the Agence France Press news agency, the lead funder of the research was the Bill & Melinda Gates Foundation, which has poured close to $100 million into the development of gene drive technology — especially via the research consortium Target Malaria — with the aim of eradicating the disease.