> "Interestingly, we consistently identified one marker that has previously been associated with tobacco use," Hou explained, "suggesting a potential shared epigenetic regulation between tobacco and marijuana use."
Well, I guess tobacco is something else that causes epigenetic changes.
As I understand it, epigenetic changes are your genome's response to the environment, so basically everything causes them to fluctuate on some level or another.
https://news.ycombinator.com/item?id=40477130