December 28 (UPI) – Scientists at Texas A&M have developed a new technique for altering mosquito genes – the new technology will cause genetic changes to delete themselves from the mosquito’s genome.
Thanks to the breakthrough described in Royal Society B’s Philosophical Transactions on Monday, researchers can now test experimental gene manipulations without permanently altering a mosquito’s genome.
“People are wary of transgenes spreading uncontrollably in the environment. We believe our strategy can potentially prevent this from happening,” said Zach Adelman, professor of entomology at Texas A&M College of Agriculture, in a press release. “The idea is, can we program a transgene to remove itself? Then the gene won’t persist in the environment.”
“It really comes down to how you test a gene drive in a real-world scenario.” Adelman said. “What if a problem occurs? We believe our path is a way to conduct risk assessments and field tests.”
Most genetic engineering strategies to contain mosquito populations – and their ability to spread diseases like malaria – require the combination of gene edits with a gene drive. A gene drive causes the altered DNA to spread rapidly through a population.
“A number of high-profile publications have talked about using a gene drive to control mosquitoes, either to modify them so they can no longer transmit malaria parasites or to kill all women and die the population,” Adelman said.
In the new article, Adelman and his research partners describe a new strategy for testing gene drive systems that expire after a certain time or a certain number of mosquito generations.
The novel technique uses a cellular process that all animals rely on to repair damaged DNA.
In every cell nucleus, repair enzymes are constantly looking for repeated genetic sequences that contain a broken genetic code. The enzymes delete everything between the repeated sequences.
To use this process, the researchers plan to introduce fruit flies and mosquitoes in the laboratory with a gene drive, a DNA-cutting enzyme, and a small DNA repeat.
Once the DNA-cutting enzyme is in place, the insect’s own repair enzyme should chase the rift and remove the gene drive and small DNA repeat from the insect’s genome.
Adelman and his research partners are set to receive $ 3.9 million from the National Institute for Allergy and Infectious Diseases to test and improve their self-extinguishing genetic engineering.
The research team has already started testing various gene propulsion systems to see how fast they move through a population before the DNA-cutting enzyme can stop their spread.
“We assigned different failure rates to determine how often the mechanism did not work as expected,” Adelman said. “The models predict that even with a very high failure rate, if it only succeeds 5 percent of the time, it will still be enough to get rid of the transgene.”