Could a Genetic Test Help Weed Out the Cannabis Strains That Don’t Work for You?

It’s been proven scientifically for years; it’s been known anecdotally for decades, and it’s a fact that could help birth the cannabis industry’s genetics-led future: marijuana works differently for different people. 

Anecdotally, this is why your best friend had that sweaty, sobbing freak-out where they yelled about their hands turning into hooves for two hours, all while you were totally calm from the same hit. Scientifically, it’s why participants carrying the COMT val/met genotype in a 2013 study committed more errors than other cannabis users carrying the COMT met/met genotype.

Granted, it’s a simple fact. Ultimately, there’s still precious little research into which genetic markers influence users’ reactions to cannabis, and any genetic effect will likely be modulated through environmental factors. 

But nonetheless, the prospect of a genetic-led cannabis industry – where users could first test their susceptibility to memory loss, paranoia, or equine hallucinations before choosing their cannabis product – is just too thrilling for some industry professionals to dismiss as fantasy. 

“So, no one is the same. Everybody is genetically different. And so we simply apply the same evidence-based science of our pharmacogenomics work to medical cannabis,” says Travis Parr, founder and CEO of Navigator Genomics Testing. Back in 2015, Parr became captivated by pharmacogenomics, a genetics field concerning patients’ individual reactions to drugs, after his own test results indicated he should change the arthritis medication that may have been harming his kidneys.

Awed by the field’s untapped potential in the cannabis industry, Parr spent the next three years recruiting consultants, geneticists, and other scientists to help launch Navigator Genomics Testing, “the first company to measure your personal genetic metabolism, response, and effectiveness for… key cannabinoids used in medical cannabis.”

The concept is thus: any medical cannabis user curious about their genetic predispositions to the drug can order one of Navigator Genomics Testing’s kits, swab the inside of their mouth, send their saliva secretions back to the company’s lab, and wait a week for their personalized report. Now informed on their sativa susceptibilities, the user can change their cannabis habits to best fit their genotype. 

“Consumers simply do a cheek swab on both sides for just a little bit of saliva. And that comes to our lab here in New Orleans,” says Parr. “We're looking to see what your drug metabolism might be and drug interactions within that as well. We test 13 genes.” 

“And it’s all color coded,” he emphasizes. “So you get a green checkmark for something that your body's going to accept and genetically respond to favorably, or a yellow triangle, which says ‘you can probably take this but you need to use a lot of caution because those drugs may have side effects that you don't want.’ And then lastly, a red stop sign that says ‘change drugs.’ And that is because your body simply does not genetically respond properly.”

“People really like it because it's in plain, simple-to-understand English,” he adds. “So it’s not like a typical lab report that you might see and other companies that do pharmacogenomics testing; it’s something that both the individual, the prescriber, and your dispensary can match pretty easily to see what's going to work best for you.”

But while its reports might be easy to decipher, the real test of Navigator Genomics’ appeal will be whether its genetic analyses are accurate enough to properly inform its customers. After all, similar cannabis genetic platforms have already come under scrutiny.

The Toronto-based company Lobo Genetics, for example, also champions a simple cheek swab test that examines three genes to “understand [a customer’s] sensitivity to THC and explore [their] short and long-term risk factors for THC-induced psychosis and schizophrenia.” But Dr Bernard Le Foll, a University of Toronto professor who helped develop the Canadian Centre for Addiction and Mental Health’s recommendations on using cannabis, is less than convinced about the company’s abilities.  

“There has been limited research done on cannabis,” he said in an interview with CBC News. “The types of studies on which [Lobo Genetics'] tests are based are done on a very small number of subjects ... I think it will require those studies to be done on larger amounts of subjects for them to be really valid.”

And on this point, Parr is in agreement. “I think [the future of the field] is more evidence-based human trials for specific cannabinoids,” he says. “And I’m not talking about mice or rat models, but people.”

But while the field of cannabis genetics may be fledgling, Parr and his team at Navigator Genomics are still confident in the science behind their tests, and champion their platform as an end to the “trial and error” period many medical cannabis users go through until they find the product that works for them. 

“I think the biggest benefit [of the test] is stopping the trial and error,” says Parr. “Maybe your bud tender recommends, ‘Oh, you're coming in because you have arthritis pain, well I like this,’ and they’re going to give you a bottle of something and they say, ‘Try that and come back in 30 days and tell me how it worked for you.’ That's trial and error.” 

According to Parr, many medical cannabis patients often go through various products blindly before their ideal balance between their drug’s efficacy and their tolerability is reached. But with a quick saliva swab of Navigator Genomics’ test, this trial by error can be completely sidestepped. 

“And drug interactions are important as well,” Parr continues. “If you took a bottle of CBD, it may not do anything at all. And that could be because your genetic response is poor or it could be because one of the other medications that you're taking is cancelling the efficacy of the CBD. In fact, our surveys recently indicated that the average consumer is taking anywhere from three to six medications, which all could conflict with their medical cannabis.”

Overseeing the company’s drug-to-drug interaction work is its medical cannabis science director, Dr Jahan Marcu. With a 15 year-long career in the cannabis science field, which has seen him serve as the chief operations officer of the International Research Center on Cannabis and Mental Health, Marcu is one of the most high-profile scientists working the US cannabis industry today. And he’s a keen proponent of Navigator Genomics’ tests and the benefit they can have for users who take multiple medications. 

“So when we we’re talking about our test, we’re wanting people to think about what they're putting in their bodies and whether or not they should consider alternatives,” Marcu says.  

“There are a couple of established examples that have been explored, such as the interactions between THC and warfarin [a blood thinning drug used to treat blood clots]. When those are taken or co administered, you'll see the levels of warfarin greatly increase in in the blood, which could lead to some harmful complications.” 

“So we’re creating this guidance, these warnings for people, for gaps in dosing and gaps in guidelines, so people can use real genetic information to help them navigate and choose their cannabis.”