People May Have a Genetic Predisposition to Cannabis Dependence

Stories surface from time to time detailing how an addiction to weed ruined someone’s life, and there are even Marijuana Anonymous meetings for those whose lives have ended up in complete disarray as a result of their lust for the leaf. Meanwhile, millions of Americans are using the herb without any issues at all. Even the federal government has come out and said that marijuana is really only about as addictive as caffeine — a drug that is not only legal but widely accepted and used by the majority of the population. So what is it about marijuana that causes some people problems, while others can use it and never wrestle with the junkie monkey?

Danish researchers believe they may finally have the answer to this question. Although not much was known about cannabis dependence up to this point, they have found evidence of a genetic variant called CHRNA2 (cholinergic receptor nicotinic α2 subunit) that appears to increase the risk of cannabis addiction.

Lead study author Ditte Demontis, an associate professor at Aarhus University in Denmark, said after comparing the genomes of over 2,000 cannabis abusers with some 50,000 healthy individuals, this variant was the common denominator in the equation. The findings were confirmed by comparing the results with an Icelandic database of more than 5,000 people with cannabis use disorder and another 300,000 without it.

It is important to point out that while it appears that some people may have a genetic predisposition for cannabis dependence, the variant alone does not automatically ensure that someone is destined to get hooked on pot. The findings, which were published in the latest Nature Neuroscience journal, only suggest that people who possess the variant are more likely to suffer from this disorder than people who do not. Researchers believe there could be dozens more genes that will eventually paint a more vivid picture of how cannabis dependency can unfold.

“Our gene variant is not enough, but it can be the first block of building the tower of information,” Demontis said.

As it stands, roughly 10% of cannabis users will experience dependency issues, according to the National Institute on Drug Abuse. But we stop short in calling it an addiction, as the habit of all highness does not come with the same repercussions as say, a jones for opioids or other harder substances.

Harvard medical professor J. Wesley Boyd explains cannabis dependency as being mild in comparison to alcohol and other drugs. “Those who quit generally experience fairly subtle physiological signs of withdrawal — a mildly elevated pulse, irritability and cravings,” he told the Conversation. “These symptoms are much less obvious or powerful than those seen when someone addicted to alcohol, painkillers, or tranquilizers suddenly stops using.”

Danish researchers now want to collaborate with American scientists to dig deeper into the issue of cannabis dependence and further substantiate their findings.

Even though Demontis believes “that what we found is the genetic risk that affects how you react to the drug,” the results still need to be compared to other databases in order to verify the results.

Interestingly, while there is some research out there that correlates schizophrenia and cannabis use disorder, the Danish research team did not find this connection. They did, however, find that people suffering from cannabis use disorder were not as educated as those without the condition.

But researchers were quick to say that their findings are in no way meant to imply that everyone who abuses marijuana falls into this category — just that there was a link between dependency and educational achievement.

While intrigued by the Danish study, scientists in the United States are cautiously optimistic about the results.

Joel Gelernter, a professor of psychiatry at the Yale School of Medicine, wants to examine the data for himself. But he told the publication Scientific American, “it’s quite likely that [this finding] adds something that’s really of interest for our biological understanding of the nature of cannabis dependence and why some people are more likely to become cannabis dependent than others.”

Howard Edenberg, a distinguished professor at Indiana University, who specializes in genetics, argues that the discovery of more genes is necessary before we have a grip on their role in cannabis dependency. “We know we’re missing a much larger part of the puzzle,” he told the news source.

Nevertheless, researchers believe their findings will eventually give medical professionals the tools to identify cannabis dependency in patients before it ever poses a problem. They hope that a more detailed exploration in this department will also lead to the creation of more effective treatments.

TELL US, do you think you have a cannabis dependency?