Federal Cannabis Is Genetically Closer to Hemp Than Commercial Cannabis, Says Study
Research-grade cannabis from the United States’ only federally authorized cultivation site is genetically closer to hemp that the cannabis offered in the nation’s dispensaries, according to a new pre-print study from researchers at the University of Northern Colorado.
This could have huge implications for researchers who are using this research-grade material for clinical studies. For one, the effects from consuming this cannabis may not be the same as those of the products bought and sold in dispensaries.
Previous research on this cultivation site
The University of Mississippi operates a facility that cultivates cannabis strains specifically for research purposes. The facility is funded through the National Institutes of Health/National Institute on Drug Abuse (NIH/NIDA) and is the sole cultivation site in the United States to have received official licensing from the Drug Enforcement Agency (DEA) to carry out operations. The cannabis materials that it provides also meets the legal and safety requirements of both the DEA and the Food and Drug Administration (FDA). While cannabis remains federally illegal, thereby restricting the ability of institutions to access cannabis from any other source while still receiving federal research funding, the NIDA cannabis source at the University of Mississippi is the most common origin point of the cannabis being used in today’s research.
While the cannabis supplied by the NIDA source is typically used as a part of trials to better understand the effects of cannabis on the human body, several studies, such as Northern Colorado’s new research, have focused on the cannabis material itself.
Previously, cannabis strains grown at the NIDA facility have been shown to contain dramatically different levels of major cannabinoids compared to commercially available cannabis. One 2017 paper found that varieties of cannabis from the institute contained only 27 percent of the tetrahydrocannabinol (THC) levels and 48 percent of the cannabidiol (CBD) levels of commercially available cannabis strains. The NIDA’s varieties also contained anywhere from 11-23 times as much cannabinol (CBN) content as commercial cannabis.
Given that previous research has indicated a difference in cannabinoid content between NIDA cannabis and commercially available products, the researchers at the University of Northern Colorado felt that a genetic investigation of the cannabis source was warranted to determine if the NIDA cannabis is also genetically distinct from the more popular commercial strains.
NIDA cannabis shares “genetic affinity” with hemp
The new study looked at 49 cannabis samples, including varieties of wild hemp, cultivated hemp, high CBD cannabis, and several cannabis strains from each of the three broad categories of Sativa, Indica, and Hybrid, alongside two samples of NIDA cannabis. DNA was extracted from each sample, and using the programs GENALEX, STRUCTURE, Maverick, and EDENetworks, it was possible to visualize the genetic relationships between each sample.
Clustering analysis of the genetic variation shows the drug-type strains (Sativa, Indica, Hybrid, and high CBD) all occupying the same character space, with the hemp samples clearly separated. Given that hemp and cannabis are known to be genetically different, this result is expected. The NIDA cannabis samples, however, cluster within the same space as the hemp samples, implying a closer genetic makeup than previously thought.
As with the clustering analysis, the other genetic analyses collected in the study indicated two major genetic groups, one containing mostly hemp samples, the other consisting of mostly drug-type samples. Consistently, both NIDA samples were grouped together with hemp.
“Our results clearly demonstrate that NIDA cannabis samples are substantially different from most commercially available drug-type strains, sharing a genetic affinity with hemp samples in most analyses,” the researchers wrote in the paper. “To our knowledge, this is the first genetic study to include research grade marijuana from NIDA, and its placement with hemp samples was unexpected.”
Consequences for research
As a growing number of states elect to pass their own cannabis law reforms, it is important that the research being carried out by institutions properly reflects the experiences that the general public will be having with the drug. This reflection of reality would ensure that the potential benefits of medical cannabis treatment are fully researched and could keep all cannabis consumers informed of the potential long-term risks of consumption. In light of this finding, there are concerns that cannabis research that uses material from the NIDA might not be fully representative.
Scientists, advocacy groups, and even professional institutions have been urging the Justice Department to expand the current cannabis cultivation program for research. Recently, the American Psychological Association submitted a letter to Attorney General William Barr, asking that he move the Justice Department to review the applications it has received so far for cannabis cultivation licenses. By approving these new facilities, it is hoped that this might bring forth a greater diversity of cannabis varieties for institutions to study, and in doing, ensure a more representative body of academic literature.