Researchers at UC San Diego School of Medicine, in collaboration with genetic testing company 23andMe, have identified genome regions associated with cannabis use and uncovered new links to psychiatric, cognitive, and physical health outcomes. The findings, published on October 13, 2025 in Molecular Psychiatry, may inform prevention and treatment strategies for cannabis use disorder.
The study analyzed genetic data from 131,895 23andMe research participants who answered survey questions about lifetime cannabis use and frequency of use. Two key genes emerged: Cell Adhesion Molecule 2 (CADM2), involved in cell assembly and nerve cell signaling in the brain, and Metabotropic Glutamate Receptor 3 (GRM3), which facilitates communication between neurons and long-term brain plasticity. CADM2 has previously been linked to impulsive personality, obesity, and cancer metastasis, while GRM3 is already associated with psychiatric disorders including schizophrenia and bipolar disorder.
A secondary analysis identified an additional 40 genes associated with lifetime cannabis use and four genes associated with frequency of use. When researchers analyzed genetic correlations with thousands of traits across datasets from the National Institutes of Health’s All of Us Research Program and Vanderbilt University Medical Center’s biobank, they found lifetime and frequency of cannabis use genetically correlated with more than 100 traits including psychiatric conditions like schizophrenia, ADHD, anxiety and depression; cognitive traits such as executive function and risk-taking; and physical health conditions including diabetes, chronic pain, and coronary artery disease. Cannabis genetics were also associated with increased risk for tobacco use, infectious diseases including HIV and viral hepatitis, and autoimmune diseases.
Currently, no FDA-approved drug therapies exist to treat cannabis use disorder. The authors hope their biological discoveries will support future identification of therapeutic targets and preventative interventions.
This article is an AI-assisted summary. All facts and figures are drawn from the original report: https://today.ucsd.edu/story/large-genetic-study-links-cannabis-use-to-psychiatric-cognitive-and-physical-health