Thread: Marijuana and gene activation?

Hi all.

I was browsing through Facebook and found a discussion about the benefits and dangers of marijuana use. One person stated that marijuana has the ability to "activate genes" that cause schizophrenia and similar conditions.

Now, I'm not exactly an expert on the subject and personally do not hold much of an opinion about the use of marijuana. However, I have not been able to find any substantial resource that adequately explains how (and if) this happens. I'm a bit apprehensive to believe that marijuana can "activate" genes (is there even specific genes for schizophrenia?) but as I said, I don't know much at all.

Does anyone know anything about this? Enlighten me!

No need to post this in NH- you're not proposing a new hypothesis, you're asking a question! The users in Biology are more likely to be able to answer this.

I would say that I've heard (and this is very vaguely recalled) there's some good evidence linking the active ingredient in marijuana to clinical depression. The extent and quality of the link I don't know. Might just be a correlation (after all, depressed people will tend to want to do drugs) or it might only be linked to binge usage. Certainly it wouldn't be a surprising connection, though I'd also be unsurprised to see similar connections with more socially acceptable drugs such as alcohol!

Sorry about posting it in the wrong section!

Thank you for your reply. I definitely agree that drugs like marijuana can correlate very well with depression. Although, I'm wondering if marijuana actually causes depression or just worsens it. Very interesting indeed!

Found this through Google, I'm not sure how old it is though:

"Research on the genetic causes of clinical depression has attempted to identify one or more specific genes that may lead to the development of a depressive illness. Although there have been a number of studies that appear to name a particular gene as the culprit there has been little consistency among their results. However, the outcome of some research has suggested that there may be specific genes that cause clinical depression to develop within certain families and not in others.


At this time there is much that we do not know about how genes may predispose a person to a depressive illness. Research has yet to identify a clear link between a specific gene and a vulnerability to depression in everyone. Rather than the possibility of only a single gene being responsible for the development of clinical depression, it appears to be more likely that a number of genes acting together may cause a person to become vulnerable to depression.


Just because a person inherits a gene that predisposes him or her to a depressive illness, it does not mean that he or she is destined to develop major depression or bipolar disorder. It is believed that a genetic influence is only partially responsible for causing depression. Other factors may also play a role."
All About Depression: Causes

I imagined this would be the case. Having specific genes for depression suggests that they either would have conferred an advantage for natural selection at some point in your ancestors past (unlikely), or that they're dormant and become activated in later life (i.e., generally after reproduction); in which case, stimulants that can "activate" these genes may increase susceptibility to clinical depression. Although, at this point in time more research is required to determine if it's correlation or causation with marijuana usage.

Personally, as with most illegal drugs, I feel media bias and the placebo effect have more to contribute to the negative views and side effects of their usage. If you're told before you take a drug that it causes paranoia and depression, even if it doesn't, you would be more likely to experience such effects than if you were told there were no side effects. If you're a regular marijuana user and become depressed you would be likely to pin the blame on the drug due to the many cases reporting links between the two. Also, marijuana usage is a broad term, there are some people who will consume it infrequently and in small amounts, and others who get high all day everday, but the two extremes often get lumped into the same category when the media are reporting on depression and schizophrenia.

Before you could unequivocally state that marijuana activates or up-regulates genes that cause depression, you would first need to identify these genes in the human genome, that is, of course, if they even exist.

Interesting - thank you!

I certainly believe in the media and placebo effect's influence on the side effects of many drugs, nowadays.