Individuals who have genes which place them at a higher risk of schizophrenia also have a higher rate of marijuana use according to a new medical research study. Study leader King’s College London followed up on previous studies which showed there was a link or connection between schizophrenia and marijuana use, but until the latest study the exact association between the two were not fully clear. The study results were published in Molecular Psychiatry, and they show that individuals who have certain genetic factors are more likely to engage in marijuana use and at a higher risk for schizophrenia/. The link does not mean that marijuana use causes schizophrenia, only that the same genes play a role in both.
According to lead study author Robert Power, who is associated with the Institute of Psychiatry at King’s College London, “Studies have consistently shown a link between cannabis use and schizophrenia. We wanted to explore whether this is because of a direct cause and effect, or whether there may be shared genes which predispose individuals to both cannabis use and schizophrenia. We know that cannabis increases the risk of schizophrenia. Our study certainly does not rule this out, but it suggests that there is likely to be an association in the other direction as well — that a predisposition to schizophrenia also increases your likelihood of cannabis use. Our study highlights the complex interactions between genes and environments when we talk about cannabis as a risk factor for schizophrenia. Certain environmental risks, such as cannabis use, may be more likely given an individual’s innate behavior and personality, itself influenced by their genetic makeup. This is an important finding to consider when calculating the economic and health impact of cannabis.”