Did you know that mosquitoes kill at least 725,000 persons every year? They truly are one of the world's deadliest animals which is the reason why scientists from all around are trying to find new ways of dealing with them.
Controlling mosquito populations and preventing them from transmitting disease at times through genetic engineering is one way of doing that. Now, a new Texas A&M AgriLife Research project has plans of enabling "test runs" of the proposed changes in mosquitoes that are automatically deleted from their genetic code.
Controlling genetic modifications
Researchers have used genetic engineering in the past to modify mosquitoes in a way that they pass on infertility, don't grow wings, can't spread malaria, or have impaired smell. However, as New Atlas reports, this sort of modification can have harmful consequences that may be impossible to reverse when released into the wild.
the new Texas A&M AgriLife Research project aims to make sure these genetic modifications are automatically deleted after a period of time.
Zach Adelman, Ph.D., a chief investigator on the project, states, "People are wary of transgenes spreading in the environment in an uncontrolled manner. We feel that ours is a strategy to potentially prevent that from happening. The idea is, can we program a transgene to remove itself? Then, the gene won’t persist in the environment."
Three potential ways
After evaluating three potential ways of achieving this goal, researchers decided to focus on one that uses a method used by all animals to repair damaged DNA. The project's proposal is to introduce a "gene drive", which is a genetic component designed to force the spread of modified genes in a population, along with a DNA-cutting enzyme and a small repeat of the insect's own DNA.
In theory, researchers think that once the introduced enzyme cuts the DNA, the mosquito's own repair tools will take action and cut out the genes and other sequences for the gene drive.
The team has already started testing different gene drives in order to see a gene drive spread through a lab insect population. They expect to see the added genes disappear after a few generations.
$3.9 million in funding from the National Institute of Allergy and Infectious Diseases will be given to the project over the next five years for the development of the self-deleting gene technology.
"We assigned various rates of failure for how often the mechanism does not work as expected,” Adelman says. "The models predict that even with a very high rate of failure, if it succeeds just 5% of the time, that’s still enough to get rid of the transgene."
The first results were published in Philosophical Transactions of the Royal Society B titled "Making gene drive biodegradable."