Genetically modified organisms such as crops that withstand harsh climates and fish that grows faster have many supporters among the scientists. But what if invasive organisms run wild? Will people manage to stop a strain of bacteria that have escaped the lab? Now, scientists have found an innovative solution: self-destructing DNA.
The new system features cutting-edge gene-editing tools designed to destroy DNA once a particular organism leaves its designated area, eradicating not only the cell but also its genetic information. This is called a "kill switch," which means erasing any experimental genetically modified organisms before they can run wild.
With the widespread use of GMOs, researchers started seeking various containment techniques. Earlier this year, Harvard scientists presented a kill-switch system based on the use of amino acids. That system ensured the destruction of synthetic organisms if they stop getting a particular amino acid, found only in the containment area. So cells would be unable to survive in the wild, and the risk that the organisms would get accidentally released can be reduced to minimum.
But the brand-new system is much more effective as it targets the DNA itself. Not only will the system kill cells, but the genetic information in them will be erased as well. That's especially useful for commercial GMOs treated by the companies as trade secrets. The system is so precise that it can affect specific portions of DNA, enabling a company to eradicate only the modified genes.
This has become possible due to new system called CRISPR. One of the most promising developments in biotech, CRISPR is a gene-editing system that represents naturally occurring molecules that are capable to cut out and replace parts of a cell's DNA. Scientists even managed to apply the system to change living genes and then modify the DNA of human embryos, causing heated debates in bioethics circles.
The kill-switch system zeroes in the DNA-removal part of CRISPR, eradicating genes completely rather than replacing them. During the experiments researchers used E. coli bacteria and pre-established trigger mechanisms to test out the system. If the limited test model came in contact with a particular sugar molecule arabinose, it triggered the CRISPR system to erase a specified portion of the E. coli DNA, as a result the cell would die.
The scientists continue their research and the current version of the system is expected to become more complex. The arabinose trigger works well in the lab, but a field-ready version of the system will require a more complex trigger.