Scientists in California are reporting they’ve successfully genetically engineered a strain of mosquitoes that can not be infected by the malaria parasite and so, they can not transmit it to humans.
Advertisement
It involves inserting parasite-blocking genes in the DNA of Anopheles stephensi mosquitos, which are a leading vector of malaria in Asia, to ensure that these genes are passed on to the bugs’ offspring.
Distinguished Professor of molecular biology & biochemistry, Anthony James, said in a statement that the new strain of mosquitoes show stronger possibilities that the technique can be adapted for eliminating malaria. They created a genetic “cassette” comprising the antimalaria genes and a DNA cutting tool that, when injected into the mosquito embryo, targeted a specific location in the germ line DNA to insert the genes.
Nearly 100 percent of offspring – 99.5 percent, to be exact – exhibited this trait, which James said is an incredible result for such a system that can change inheritable traits. “The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations”, James added.
This new model represents a notable advance in the effort to establish an antimalarial mosquito population, which with further development could help eradicate a disease that sickens millions worldwide each year.
A gene-editing technique creates mosquitoes resistant to the malaria parasite.
Zhang, a biological engineer, led the first team of researchers to employ the CRISPR-Cas9 editing technique on human cells. They coupled the malaria resistance gene with one that makes mosquitoes’ eyes red, so they could measure whether the resistance gene was passed on.
The hope is that this plan will eventually wipe out the disease. The California team took safeguards including special lab security and using a mosquito species that can’t survive in California’s climate.
“This work suggests that we’re a hop, skip, and jump away from actual gene-drive candidates for eventual release”, Kevin Esvelt of the Wyss Institute who was not involved in the work told Nature. Although the disease is curable and preventable, it claims a large number of lives.
World Health Organization estimates 438,000 people have died of malaria this year alone, 91 percent of which occurred in Sub-Saharan Africa.
Advertisement
But in conjunction with treatment and preventive drugs, future vaccines, mosquito-blocking bed nets and eradication of mosquito-breeding sites, it could play a major role in sustaining the elimination of malaria, James said.
