Strains by the same name sold at different dispensaries have significant genetic variations that could result in inconsistent physiological effects on consumers, according to recently released research.
Doctoral candidate Anna Schwabe, who is studying population and evolutionary genetics at the University of Northern Colorado in Greeley, tested 122 strains of cannabis in Washington, Colorado and California. She tested strains that were widely available — including strains like Golden Goat, Blue Dream, Purple Kush and Green Crack, among others — and compared their genetic makeup which often varied widely.
Her results were surprising, considering many growers think they’re getting clones of the same plant.
“I think, especially for cannabis, you need to know what you’re starting with,” Schwabe said. “It’s going to change from growhouse to growhouse. We want to reduce the chance for variability.”
In her research, Schwabe also did not find a significant genetic difference between indica and sativa species.
The genetic variation between cannabis products that are labeled the same is problematic for both growers and consumers who often expect one product with expected physiological effects and instead receive another, depending where they’re buying their products.
“I use the examples of Skittles and M&Ms. If you reach in a bag of M&Ms and get a Skittle, you’re going to be really surprised,” Schwabe said. “For me it’s really important that what’s outside the package match what’s inside the package.”
Schwabe faced significant hurdles while performing her research. Working on a shoestring budget, she traveled to Washington and California during her spring break. Because she couldn’t legally transport the cannabis across state lines, Scwabe ground up the plant material and used centrifuges at labs where friends worked. She also couldn’t bring the product intact onto campus, and had to prepare the samples off campus for later testing at the university.
Schwabe used an inexpensive dehydrator to dry her samples. Because the cannabis didn’t need to be spun all that quickly to extract the DNA, at times she used a salad spinner when a centrifuge wasn’t available. After dehydrating and spinning the strains, she brought vials of the prepared samples onto campus for genetic testing.
“It’s grassroots,” Schwabe said. “You have to get creative when you don’t have any funding.”
The lack of uniform strains that are replicated isn’t just worrisome for consumers who could be getting a different product each time they enter a different dispensary.
Growers can’t benefit from making proprietary, unique strains because cannabis is labeled as a non-eligible commodity by the United States Department of Agriculture (USDA), and therefore not qualified for the same protections that farmers who grow a unique type of tomato or apple receive.
“They’re making these stellar new breeds and anybody could steal a cutting and grow it and call it something else,” Schwabe said. “Anybody can say they had it.”
Schwabe’s research was first presented to the Institute of Cannabis Research in April of 2017. Her work was made available to the public in late May of 2018.
“When dispensaries are taking things for testing, they’re taking the right thing, but maybe the customer isn’t always getting what was tested. That’s another point of my research,” she said. “I think it’s a cautionary tale. Just because the strain is called this doesn’t necessarily mean it’s going to be the same everywhere.”