US researchers have created genetically-modified mosquitoes resistant to a malaria parasite, raising the possibility of one day stopping the spread of the disease, a new study says.
The genetically-engineered mosquitoes outbred natural mosquitoes
when fed malaria-infected blood from mice, according to the study
published Monday in the Proceedings of the National Academy of
The research offers the possibility of controlling malaria by
introducing the genetically altered insects into the wild and
having them take over from their natural cousins.
The scientists at Johns Hopkins University in Baltimore,
Maryland combined equal numbers of genetically engineered and
natural mosquitoes in the laboratory and let them feed on
GM mozzies wins evolution race
The genetically-altered insects survived in greater numbers and
laid more eggs. After nine generations, 70 percent of the
mosquitoes were genetically-modified compared to 50 percent at the
outset of the experiment, Marcelo Jacobs-Lorena and his colleagues
The study suggested that when feeding on malaria-infected blood,
"transgenic malaria-resistant mosquitoes have a selective advantage
over non-transgenic mosquitoes," the authors wrote.
The lab-altered mosquitoes competed equally well with natural
insects when fed non-infected blood but did not outbreed their
natural counterparts in that case, according to the study.
For the strategy against malaria to be effective, transgenic
mosquitoes would have to outbreed the natural insects when feeding
off untainted blood.
Not ready for prime time
Further research was still needed before the altered insects
could be released into the wild, as only a small percentage of
mosquitoes in nature are exposed to malaria, the authors wrote.
Still, the research carried "important implications for
implementation of malaria control by means of genetic modification
of mosquitoes," the authors wrote.
The experiment used the malaria parasite P. berghei, and not the
more dangerous parasite - Plasmodium falciparum - responsible for
the most serious malaria affecting humans.
Each year 350 to 500 million people are infected with malaria
and 700 000 to 2.7 million die from the disease, including more
than a million children in Africa, according to the World Health
Organization. – (Sapa-AFP)
Glowing mosquitoes created