A white mushroom designed using CRISPR-cas9 gene-editing technology may spell the end of regulation of genetically modified foods. A new ruling by federal regulators could have wide-ranging consequences for the regulation and labeling of newly manufactured food products.
Food regulations are at an impasse with the new development. The developers removed segments of the genetic code of Agaricus bisporus, the most commonly consumed species of white mushroom in the United States. However, they did not insert new genes, so their new variety of fungus may be completely unregulated, due to a bureaucratic loophole.
When genetically modified organisms (GMO's) were first being developed, most contained genes from bacteria. This allowed the U.S. Department of Agriculture to regulate the foods under their authority to regulate pests capable of attacking plants.
White mushrooms are particularly sensitive to browning, a condition which quickly makes them unsaleable. Even a small amount of damage can trigger an enzyme which quickens the reaction.
By removing one segment of genes from the mushroom, the creators were able to form a variety of the fungus that will not turn brown as quickly. This is not the first food product to be made resistant to browning through the removal of genes. In 2015, a new variety of potato was developed that has the same quality.
"The anti-browning property significantly improves the appearance and shelf life of white button mushroom, and is expected to facilitate automated mechanical harvesting .... the genome-edited mushroom has small deletions (1 to 14 bp) in a specific polyphenol oxidase gene, but contains no foreign DNA," Yinong Yang of Pennsylvania State University wrote in a letter (PDF) to the USDA.
The USDA has now ruled they will not regulate the newly produced mushroom, as no genes from bacteria were utilized in the development of the new fungus.
"APHIS has concluded that your CRISPR/Cas9-edited white button mushrooms described in your letter do not contain any introduced genetic material," The Animal and Plant Health Inspection Service (APHIS) responded (PDF).
Polyphenol oxidase (PPO) genes, which drive the browning process, were targeted by researchers in the study. Of the six PPO genes, the team removed one, reducing browning by 30 percent.
Labeling of GMO's has become a hot topic in politics over the last few years. A law requiring labeling of such products in the state of Vermont already had an impact throughout the food industry.
Image: Stew Dean | Flickr