With genetic modification techniques becoming more and more prevalent in the food industry, many questions surrounding the practice are coming into the limelight. One question that experts are asking is what constitutes a genetically modified organism (GMO): if researchers snip DNA from a vegetable without adding new genes, is this enough for it to be considered a GMO?
Now, Penn State University researcher Yinong Yang has used CRISPR/Cas9, the popular gen-editing tool, to remove a piece of DNA from a gene in a white button mushroom. By snipping the DNA, Yang was able to disable the gene and reduce the mushroom's production of the polyphenol oxidase enzyme and increase the time it takes for the mushroom to turn brown.
Yang's process has similar results to those used by scientists that insert genes into plants in order to silence specific genes, creating non-browning apples and potatoes. However, while these foods are considered GMOs due to the addition of genes, the classification of processes such as Yang's is still debated.
However, this debate might now be closer to an end. After consulting with the U.S. Department of Agriculture (USDA), Yang found that they would not regulate his food.
"APHIS (Animal and Plant Health Inspection Service) has concluded that your CRISPR/Cas9-edited white button mushrooms as described in your letter do not contain any introduced genetic material," they said. "APHIS has no reason to believe that CRISPR/Cas9-edited white button mushrooms are plant pests."
It is the first time that the department has looked at a crop edited using CRISPR and could pave the way for more in the future.
Despite its success with the USDA, it's not completely out of the woods yet and could still face scrutiny by the Food and Drug Administration (FDA).
"Anything for food or feed consumption, usually the company submits the data to FDA for approval," says Yang, although he notes that "this process is voluntary, not mandatory."
Gregory Jaffe, biotechnology program coordinator at the Center for Science in the Public Interest, believes that Yang's mushroom reveals the weaknesses in the government's current regulatory process.
"The regulatory system is not science-based, but trigger-based," he said, pointing to the fact that the USDA only regulates crops that present a risk of leading to weeds or pests in other plants.
"You could have a situation where a crop may actually have some risk, but doesn't get regulated by USDA, and you could have things that don't have any risk, but which are regulated," Jaffe added.
