Scientists from Macquarie University and the California Institute of Technology in the USA have developed a novel method designed to create controlled, reversible genetic modifications of wild populations, Genetic Engineering & Biotechnology News (GEN) reported.
In the study “Altering traits and fates of wild populations with Mendelian DNA sequence modifying Allele Sails” – published in Nature Communications on 13 August, the team said the technique could address some of the regulatory challenges and public concerns associated with existing genetic modification methods.
According to lead author Maciej Maselko, from Macquarie University’s Applied Biosciences department, the ‘Allele Sail’ approach would allow beneficial genetic changes to spread through a population without leaving “foreign DNA” behind.
“Allele Sail offers a way to change the traits and fates of wild populations in ways that may be more acceptable, as the genetically modified part is introduced at low frequencies and usually won’t last forever,” Maselko was quoted as saying.
Genetic engineering could address major global challenges by altering the genetic makeup of certain wild populations, for example, to combat mosquito-borne illnesses such as malaria, or stop the spread of environmentally harmful invasive pests like cane toads, GEN wrote on 13 August.
However, there was public concern about introducing genetic modification into wild populations and many regulatory constraints, the report said.
Those concerns included: modified organisms could contain foreign deoxyribonucleic acid (DNA) causing unpredictable ecological consequences over time; engineered genes could spread to other species with unknown impacts on ecosystems; and the possibility that genetic modifications could not be reversed once introduced.
Traditional methods of genetic modification can also lead to a rapid spread of engineered genes within a population, raising both ecological and ethical questions, according to the research team.
In response, many regulatory frameworks had been introduced to address genetic modification, presenting further challenges, GEN wrote.
Current regulations often distinguished between genetically modified organisms (GMOs) and those with edited existing genes, creating barriers for approval and implementation, the report said.
“The Allele Sail system uses a gene editor to make specific DNA changes to an organism’s genome. But unlike other genetic modification methods, the editor is inherited normally and does not increase in the population,” Maselko explained.
“However, the edits it creates can spread rapidly, potentially making desirable traits common.”
While other genetic modification techniques like gene drives, which quickly spread engineered genes through a population, the Allele Sail introduced genetic changes using an editor that remained at low levels and could potentially be removed from the population completely, Maselko said.
Using computer models, the researchers ran tests to see how an Allele Sail system would work under different scenarios.
They found that releasing even a small number of organisms carrying the editor could make the edited genes common in a population.
This approach could be used to help conserve endangered species, control invasive species, or reduce the spread of insect-borne diseases, the team said.
“Current regulations often treat transgenic organisms as genetically modified, but their edited offspring as non-GMO,” Maselko said.
“In this context, an Allele Sail provides a way to alter wild populations that may be more acceptable.”
However, Maselko acknowledged that any genetic modification of wild populations would be “controversial” and the potential environmental impacts would need to be carefully studied.
