A group of researchers from Imperial College in London have recently conducted a study in which CRISPR-Cas9 genomic editing was used to eliminate malaria-infected mosquitoes. In their findings published in Nature Biotechnology, scientists were able to eradicate a controlled population of mosquitoes in as few as 7 reproductive generations. The project was funded in part by the Bill and Melinda Gates Foundation, the UK’s Biotechnology and Biological Sciences Research Council, and the Massachusetts General Hospital program.
Specifically, the researchers target what they denote as a “doublesex” gene that is unique to the mosquito’s gender determination. Unlike the male version of the gene, the female version contains a unique exon that the researchers utilized to eradicate females in the population. By doing so the team effectively reduced the population composition to consist solely of males, causing cessation of reproduction.
Using CRISPR target disruption of this exon region in the mosquito genome, the researchers blocked the formation of complexes that had no effect on male growth and fertility but led to sterility in the females who carried two copies of the gene. The researchers report that this process allowed led to “100% prevalence within 7–11 generations while progressively reducing egg production to the point of total population collapse.” These modified females displayed both male and female characteristics, rendering them unable to bite and lay eggs.
The UK researchers created these genetically modified mosquitoes specifically for use as a weapon against malaria. 216 million cases of malaria were documented in 2016, as per World Health Organization data, and 445,000 of these cases resulted in death. In addition, most fatalities resulting from malaria are represented by children under the age of five. The need for preventative measures against the parasite is eminent, and with their new research findings, the Imperial research team is optimistic that they could be developing a potential candidate.
“We are very excited,” said research leader Andrea Crisanti, a professor of molecular parasitology at Imperial College London. “This is a game-changer. This is a completely new era in genetics.” Kevin Esvelt, MIT evolutionary engineer and genetic researcher who was not part of the research confers, describing the paper to be “extraordinary”.
Using Crispr, researchers were able to wipe out an entire population of malaria-touting mosquitoes https://t.co/O1GTI3T4wR
— WIRED (@WIRED) September 24, 2018