May 12, 2016

Gene-Edited Mushroom Is First CRISPR-Generated Product to Avoid Federal USDA Regulation

Genetic alteration since the beginning of the biotechnology age has largely relied on the introduction of new genetic material into an organism to create a genetically engineered (GE) bacterium, plant or animal (also known as a genetically modified organism, GMO). Regulatory schemes reflected that dominant paradigm. Now, however, the use of gene-editing technology for genetic manipulation in plants can result in genetically altered plants that bypass the regulatory requirements for the introduction of standard GE plants into the marketplace. The traditional genetic engineering of crops employed the introduction of foreign genetic material into the crop; such gene transfer generally triggered formal review of the altered product because of the phenotype conveyed by the introduced gene(s), or because of the use of a vector that had plant pest characteristics. A GE plant product would trigger review if the newly introduced trait posed environmental or other safety-related risks. The review was conducted by the Animal and Plant Health Inspection Service (APHIS) of the USDA, pursuant to its statutory authority under the Plant Protection Act of 2000. (Depending on the product, additional oversight by the FDA or EPA could be required). Today, genetic alteration has moved beyond simple gene transfer into more precise techniques for changing the genome of an organism. Now, in a regulatory first, APHIS has made a determination that a white button mushroom altered by CRISPR/Cas9 gene editing technology to exhibit reduced browning is an “unregulated article” that will not require the kind of formal review usually applied to traditionally genetically engineered products containing foreign DNA: 
APHIS does not consider CRISPR/Cas9-edited white button mushrooms as described in your October 30, 2015 letter to be regulated. 
Here, CRISPR/Cas9 gene editing technology was used to introduce a small deletion in a polyphenol oxidase gene in the mushroom, with the result that the altered enzyme cannot produce the browning that shortens shelf life. The final product has no foreign DNA and no plant pest characteristics. This decision by APHIS follows earlier determinations that have resulted in at least 10 genetically altered products being approved without requiring a formal review. These products have been produced with, e.g., techniques that did not rely on the introduction of new genetic material using any plant pest vector, or non-CRISPR gene editing technologies. This shift in regulation highlights how modern genetic alteration writ large encompasses multiple technologies, some of which fall into an existing regulatory mandate, and some of which do not. The central theme of biotechnology regulation to date has been to focus on the product, not the process. As far back as the introduction of the federal Coordinated Framework for Regulation of Biotechnology in 1986, the prevailing scheme ensured that genetically engineered products would not be singled out for heightened review simply because of the way they were produced. The product was the focus; more precisely, the actual phenotypes of the GE plants or insects were evaluated to identify traits that required additional oversight. The traditional dichotomy between product-based or process-based paradigms for regulation biotechnology products has been criticized as a poor fit for the realities of the biotech marketplace. Evidence for an evolution of the regulatory scheme has been provided by the Obama administration’s announcement of a deliberative process to overhaul and modernize the regulation of biotech products, with the recruitment of the FDA, EPA, and USDA in the process (see earlier post). This regulatory renewal will no doubt eliminate a strict focus on gene transfer as the only genetic technology producing altered organisms, and strive to broaden the definition of the field of genetic alteration to reflect new realities, such as CRISPR and other gene-editing technologies. Then the calculus of risk/benefit analysis will need to be applied, in the context of emerging genetic technologies where risk profiles are not yet established.

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