Not Made to Survive
Gene editing technologies are rapidly advancing. Tools like CRISPR-Cas9 have the potential to help us reverse and even eradicate diseases such as HIV, cancer, and so much more. However, as we genetically modify organisms, we run the risk of them mating with their non-modified counterparts, which could irreparably change wild species and disrupt whole populations and ecosystems.
“This is a problem that has been recognized for a while,” said Maciej Maselko, a postdoctoral researcher at the BioTechnology Institute and the University of Minnesota’s (U of M) College of Biological Sciences (CBS), in a U of M news release.
While previous attempts to prevent this breeding have centered on quarantining the modified organisms, Maselko has developed a tool that could prove to be more successful as it makes it impossible for modified species to effectively breed with their wild versions. He calls it “synthetic incompatibility.”
Natural regulatory functions in the cells of living organisms determine whether genes are turned on or off. When on, they produce proteins, and when off, they don’t. These regulatory systems are integral to survival as too much or too little of certain proteins could be harmful.
Maselko’s synthetic incompatibility technique takes advantage of this natural process.
First, Maselko modifies a specific gene in a way that doesn’t change the organism’s behavior. He then modifies the organism so that it produces a protein that looks for the unmodified version of that specific gene, which it would only find if the modified organism tried to breed with its unmodified counterpart.
If the protein finds that unmodified gene, it is instructed to turn it on. Being stuck in the on position results in the production of too much of the protein, effectively killing the organism.
Maselko and his team tested this technique with brewer’s yeast. When the genetically modified yeast attempted to breed with the “normal” yeast, the offspring inflated because of the excess proteins, swelling up like balloons until they popped. This prevented the modified organism from being able to reproduce.
Maselko has already considered several potential applications for his synthetic incompatibility tool.
“We get a lot of medications from plants, but the plants that naturally make those medications only do so in really tiny quantities,” he told U of M. “One of my goals is to see if we can get the genes responsible for making those drugs into plants that we can grow on massive scales, such as corn, rice, or wheat.”
He also thinks it could be used to help clean up the environment. Scientists could engineer fish to break down the contaminants polluting water without worrying that they’ll breed with the wild versions of their species.
“Fish don’t naturally have the enzymes necessary to break down some of these compounds, but we know of enzymes that exist that can,” he said in the news release. “That’s one of the next steps we’re looking at.”
While Maselko’s tool is unlikely to completely ease the minds of all those who are hesitant about our increasing control over genetics, it could help alleviate some of the risks associated with genetic modification and allow us to take advantage of the technology in ways that have tangible benefits for humanity.