USDA Plant-Pest Review Clears Genetically Engineered Hemp for Cultivation and Breeding
A genetically engineered Cannabis sativa developed to produce little or no THC and cannabichromene (CBC) is not subject to regulation under the U.S. Department of Agriculture’s plant-biotechnology rules, according to a September 25, 2023 determination from USDA’s Animal and Plant Health Inspection Service (APHIS).
The decision applies to a plant developed by Fort Wayne, Indiana-based Growing Together Research. The company’s application described a transgenic hemp line engineered through RNA interference targeting the genes responsible for producing tetrahydrocannabinolic acid synthase and cannabichromenic acid synthase. The intended result was a plant with approximately 0% THC and 0% CBC, while retaining the characteristics of its parent plant.
The modified plant also contains the Bar gene, which provides resistance to the herbicide bialaphos. In the company’s application, the gene was described primarily as a selectable marker used to identify successfully transformed plants. Growing Together Research said the modification was not expected to cause material changes to the plant’s metabolism, physiology, or development.
APHIS did not evaluate the plant as a food, drug, or consumer product. Its review addressed a narrower question: whether the genetic modification created a plausible pathway for increased plant-pest risk under 7 CFR part 340 compared with an appropriate Cannabis sativa comparator.
Based on the information submitted by the company and its own review of the plant’s biology, traits, mechanism of action, potential effects on beneficial organisms, and possible weedy impacts, APHIS found no plausible pathway for an increased plant-pest risk. The agency therefore concluded that the plant was unlikely to pose a greater plant-pest risk than comparable cultivated hemp.
That finding means the plant is not regulated under the specific APHIS rules governing the movement of organisms modified or produced through genetic engineering. The determination also extends to progeny produced by crossing the modified plant with nonmodified plants or with other modified plants that are themselves not regulated under part 340.
The decision does not eliminate every regulatory requirement. APHIS stated that the plant may still require permits or remain subject to quarantine requirements administered through its Plant Protection and Quarantine program. The agency also noted that other federal regulators, including the Environmental Protection Agency and the Food and Drug Administration, may have separate authority over particular uses or products.
That distinction is important for hemp producers. Under the 2018 Farm Bill, federally defined hemp must contain no more than 0.3% delta-9 THC by dry weight. Crops that exceed the limit can create significant compliance and financial risks for growers. A reliably low-THC variety could help reduce the possibility of a so-called “hot” crop, although the USDA determination itself does not guarantee a particular THC level in every growing environment or establish that the plant is ready for commercial sale.
Federal hemp production remains governed by USDA’s Domestic Hemp Production Program, along with applicable state, tribal, and local requirements. The FDA separately regulates products containing cannabis-derived compounds. Its guidance makes clear that removing hemp from the federal definition of marijuana did not remove the agency’s authority over foods, dietary supplements, drugs, cosmetics, or other products containing CBD or other cannabis compounds.
APHIS’s 2023 response remains valid even after a federal court vacated the 2020 revision to the agency’s biotechnology regulations in December 2024. USDA says that regulatory status review responses issued before that ruling remain valid. The decision therefore clears the described hemp plant from APHIS’s plant-pest regulations, but it should not be read as a blanket federal approval of genetically modified cannabis or of products made from it.
