TEHRAN (Press Shia) – A team of researchers at the University of Alberta has warned that the use of gene-editing technology to create virus-resistant cassava plants could have hazardous consequences.
Roughly three years ago, Devang Mehta, a postdoctoral fellow in the Department of Biological Sciences, began a study as a PhD student in Switzerland on creating virus-resistant cassava plants, the Edmonton Journal reported.
The goal of the research was to make the starchy root vegetable resistant to the devastating mosaic disease, which results in about a 20 per cent crop loss annually.
But during the study, researchers from the University of Alberta, University of Liege in Belgium, and Swiss Federal Institute of Technology found the virus was instead mutating and becoming resistant.
“We concluded that because this technology both creates a selection pressure on the viruses to evolve more quickly, and also provides the viruses a means to evolve, it resulted in a virus mutant that is resistant to our interventions,” Mehta said.
He added that that cassava plant is different in that it does not require a seed to be replanted. Instead, a piece of the plant’s stem is cut off to grow new crops, a staple grown in South America, Africa and Asia.
“The difference here is usually when a plant goes to seed, the viruses that were in that plant usually do not transmit into the next generation. Whereas in the case of the cassava, because it doesn’t involve a seed in order to reproduce, there is this potential the virus could get carried throughout generations of crops,” Mehta said.
Researchers used new gene-editing technology — CRISPR-Cas9 — to try and change the DNA of the mosaic virus in order to stop the spread of the disease in the cassava plant.
CRISPR-Cas9 is essentially comprised of two genes, CRISPR being one and Cas9 being another. CRISPR-Cas9 is prevalent in many naturally occurring bacteria, which use the system to defend against viruses.
Researchers concluded that the gene-editing technology is appropriate for many different applications where editing the genome of a plant or animal is involved. But when it comes to editing the genome of a virus, there are a new set of characteristics to consider, some of them dangerous.
“We discovered that the pressure that CRISPR-Cas9 applied to the virus probably encouraged it to evolve in a way that increased resistance to intervention,” Mehta said, noting his research team is keen to share the results with other scientists who are using the technology to engineer virus-resistant plants so they can quickly detect any similar viral mutations.