Together, these findings suggest that people born with a lot of the genetic variations that seem to predispose to schizophrenia are more likely to take cannabis than those born with few of them. The study’s samples are small, so follow-up work will be needed to confirm this result. But if it is so confirmed, that will show the link between cannabis and schizophrenia to be a two-way street. It will not eliminate, as Dr Power is quick to point out, the possibility that taking cannabis increases someone’s chances of becoming schizophrenic. But it will mean that those predisposed to the condition are indeed more drawn to the drug.