Mosquitos aren’t just a pest that nibble on you when you’re trying to get to sleep in the summertime; they’re by far the deadliest animals on the planet. According to the World Health Organization, mosquito bites cause the death of one million people each year. The majority of these are the result of malaria, one of the many human-affecting diseases these tiny bloodsuckers can carry.
For this reason, scientists trying to tackle these diseases have explored a range of potential solutions — such as gene drives, referring to tiny fragments of DNA that can be inserted into a mosquito’s chromosomes to deplete populations in various ways.
But if SyFy original movies have taught us anything, it’s that genetically tweaking organisms and then releasing them can… well, not go quite according to plan.
With that in mind, a new Texas A&M AgriLife Research project seeks to test out genetic modifications of mosquitos that would delete themselves from the genetic code after a certain period. This means that “test runs” of genetic changes could be made, knowing that everything will reset to normal after a designated period like one year (which equates to around 20 generations of mosquito).
Temporary tampering
“Rather than develop a new way to perform gene drive, our [project] provides a pathway to modify existing gene drive approaches to make them more temporary,” Zach Adelman, a Professor in the Department of Entomology at Texas A&M University, told Digital Trends. “Other approaches to remove gene drive pests rely on either releasing a second wave of genetically engineered or unmodified pests, or to just let the engineered sequences decay on their own.”
The problem with these two approaches is that the former is not very practical (“If something goes wrong during the release of gene drive pests, it is not likely the same group of scientists will be allowed to release a different version to control the first,” Adelman said), while the latter would take too long. This project could get around that, thereby lowering the risk of genetic modification without having to curtail necessary experimentation.
You may be waiting a bit longer before this theoretical project becomes a reality, however. “We are just at the start of a five-year project to demonstrate our biodegradable approach,” said Adelman. “This strategy relies on the DNA repair machinery of the insect. That’s our first step: determine some of the parameters that the insect uses to decide when to repair DNA damage, using machinery that will remove our engineered sequences, as opposed to different machinery that kind of patches over the broken ends.”
He noted that, should all go according to plan, the first set of experimental findings related to this could be released in 2021. A research paper describing this initiative was recently published in the journal Philosophical Transactions of the Royal Society B.
