Skip to main content
Premium Trial:

Request an Annual Quote

MIT Team Develops CRISPR-Based 'Kill Switch' for GMOs

NEW YORK (GenomeWeb) – Amid concerns over the potential damage that could be caused by genetically modified organisms (GMOs) should they get into the wild, a research team from the Massachusetts Institute of Technology this week reported a new technique to inactivate or kill such organisms if they escape their intended environment.

The approach uses a genetic device dubbed DNAi — a play on the name of the messenger RNA-targeting technology RNA interference, or RNAi — and is based on the genome-editing method known as CRISPR/Cas9, which involves directing a nuclease to specific parts of the genome where it causes double-strand DNA breaks.

According to a paper published in Nature Communications, DNAi constructs are designed to respond to a specific transcriptional input, triggering the CRISPR/Cas9-based degradation of target DNA while leaving untargeted DNA intact. When it comes to GMOs, DNAi could theoretically be used to destroy either the modified DNA or the organism itself upon exposure to specific molecules.

As proof of concept, the MIT scientists used DNAi to prompt genetically modified Escherichia coli to degrade certain gene segments upon exposure to arabinose, which resulted in about 99 percent of bacteria dying within two hours.

In addition to preventing the accidental release of GMOs from the lab, the MIT investigators believe DNAi could be an effective means for combating industrial espionage, such as a recent case in which a Dow AgroSciences researcher was convicted for stealing trade secrets from the company in the form of strains of a proprietary enzyme.

"For environmental and intellectual property applications, the input could be changed to connect to sensors that activate when the cells are removed from a defined media or exposed to particular conditions," such as light or oxygen, they wrote in Nature Communications. "More sophisticated control can be achieved by connecting the device to the output promoter of a transcriptional genetic circuit — for example, genetic logic to integrate signals from multiple sensors that define a cocktail of chemicals specific to a media or environment."

Because DNAi is compatible with other systems for the containment of GMOs — such as ones that trigger programmed cell death, DNA deletion, or the re-coding of the genome to require non-natural amino acids — "one can imagine combining these systems to create layers of redundancy to ensure that engineered organisms are viable in particular environments, and if they escape, they eliminate their synthetic DNA," the team concluded.