Skip to main content
Premium Trial:

Request an Annual Quote

An Unregulated Mushroom

A mushroom edited using the CRIPSR-Cas9 approach to prevent browning falls outside US regulations, the US Department of Agriculture has determined.

In the past five years, the agency's Animal and Plant Health Inspection Service has found that about 30 genetically modified organisms don't fall under its regulations, Nature News reports. That's because, it adds, the modified organisms, most of which have been plants, don't contain foreign DNA. 'Plant pest' DNA like that from viruses or bacteria, it notes, was a concern when the regulatory framework was drawn up in the 1980s and 1990s.

Many of these more recent GMOs, though, have been altered using zinc finger nucleases, TALENs, or, now, CRIPSR-Cas9.

To develop this browning-resistant mushroom, Pennsylvania State University's Yinong Yang used the CRIPSR-Cas9 gene editing approach to knock out one of the mushroom's six polyphenol oxidase (PPO) genes. This reduced the PPO enzyme activity by nearly a third and thus reduced browning.

This mushroom, Nature News says, is "the first CRISPR-edited organism to receive a green light from the US government."

It further notes that the US is considering altering its GMO regulations, and the National Academies of Sciences, Engineering, and Medicine is hosting a meeting next week to discuss advances that may come to the field in the next five years to 10 years.