Cannabis Science Study By Russo: Investigates Breeding For Terpene, Cannabinoid Ratios

Dr. Ethan Russo and colleagues recently published a paper on breeding programs for different essential oil or terpenoid profiles in cannabis.

The paper entitled “Pharmacological Foundations of Cannabis Chemovars” was printed in the journal Planta Medica. Dr. Russo is the former president of the International Cannabinoid Research Society and senior medical advisor for GW Pharmaceuticals. He has participated in much of the research and writing on the topic of terpenes and cannabinoid interactions in circulation. He’s even working with the father of modern cannabis research, Raphael Mechoulam, at the new biotech company Phytecs. 

In the paper they discuss how they’ve created breeding programs that allow the same terpene profile to be expressed in plants that are dominant in CBD, THC, a combination of THC and CBD, no cannabinoids, or even CBDV/THCV—proving that terpene profile and cannabinoid content are not necessarily correspondent. This means that myrcene or any other terpene doesn’t necessarily indicate THC or CBD content and are primarily independent variables.

Furthermore, they investigated the subjective effects of the terpene profiles and added THC vs. CBD/THC in humans. CBD reduced most anxiety, intoxication, and related effects. Myrcene-dominant terpenes created sedation; terpinolene-dominant samples produced increases in subjective energy. Samples with ocimene produced a more calming effect compared to similar profiles without that component. Chemovars containing limonene and pinene increased reported focus, particularly in the pinene chemovars. Higher limonene, ocimene, and linalool promoted inspiration, as observed from the mood metrics in the questionnaire.

The researchers found the cultivar Rainbow Gummeez to be of particular interest. The variety won and placed in multiple categories at the Emerald Cup in 2016 and, after testing, turned out to be a 1:1 THC/CBD cultivar that was terpinolene dominant. 

As the cannabis industry continues to move forward, developing the baseline for the effects of terpene profiles and how to create them in cannabis plants will be highly important. For more information visit 

Russo’s partners in the writing and development of this paper were Kevin Smith and Mark A. Lewis. Lewis is also a member of Biotech Institute, LLC, and his name is on the patent the company filed as “Breeding, production, processing and use of specialty cannabis,” which seems to cover a wide set of cannabis cultivars. Biotech Institute and the patent were written about in a recent GQ article entitled “The Great Pot Monopoly Mystery” that seemed wary of the company and those involved. It’s good to see some of Russo’s  knowledge being used to study cannabis and share the information with the public and medical establishments.