This tool lets you explore genetic variants that have been studied in relation to cannabis use and psychosis/schizophrenia risk. It parses raw DNA data from services like 23andMe and AncestryDNA and shows you your genotypes at specific locations that researchers have investigated.
Why This Exists
Cannabis is increasingly legal and accessible, but not everyone responds to it the same way. A small percentage of users (~1%) develop psychosis, and researchers have been trying to understand why. Genetics appears to play a role — certain gene variants may increase vulnerability to cannabis-induced psychosis, particularly with heavy use.
This information exists in academic papers, but it's not easily accessible to regular people. This tool is an attempt to bridge that gap — to let curious individuals see their own genotypes at these studied variants and read plain-language summaries of the research.
What This Tool Is Not
This is not a clinical risk prediction tool. It cannot tell you whether you will or won't develop psychosis. The science is still evolving, effect sizes are modest, and genetics is just one piece of a complex puzzle that includes family history, age of first use, frequency, potency, trauma history, and other factors.
Specifically, this tool:
- Does not provide medical advice
- Does not calculate a "risk score" or probability
- Does not account for gene-gene interactions or polygenic risk
- Does not consider your personal or family psychiatric history
- Is not a substitute for genetic counseling
The Science
The variants included in this tool come from peer-reviewed research, primarily:
- AKT1 rs2494732 — The most replicated finding. Di Forti et al. (2012) found daily cannabis users with C/C genotype had ~7× higher odds of psychosis vs. T/T carriers.
- COMT Val158Met — Caspi et al. (2005) reported adolescent cannabis users with Val/Val genotype were more likely to develop psychotic symptoms, though replication has been mixed.
- Various CNR1, FAAH, and DRD2 variants — Studied with varying levels of evidence, mostly preliminary.
We've labeled each variant with an evidence tier (strong, moderate, preliminary) based on replication across studies. "Strong" doesn't mean definitive — it means the finding has been reproduced more consistently than others.
Key Research Papers
- Di Forti M, et al. (2012). Confirmation that the AKT1 (rs2494732) genotype influences the risk of psychosis in cannabis users. Biol Psychiatry.
- Caspi A, et al. (2005). Moderation of the effect of adolescent-onset cannabis use on adult psychosis by a functional polymorphism in the COMT gene. Biol Psychiatry.
- Hindocha C, et al. (2020). Do AKT1, COMT and FAAH influence reports of acute cannabis intoxication experiences? Transl Psychiatry.
- Mota NR, et al. (2022). Cannabis induced psychosis: A systematic review on the role of genetic polymorphisms. Pharmacol Res.
Privacy
Your genetic data never leaves your device. All parsing happens locally in your browser using JavaScript. We don't upload, store, or transmit your data anywhere. There's no backend server, no analytics tracking your genotypes, no database of results.
You can verify this by viewing the page source or monitoring network requests — you'll see no data is sent out after you upload your file.
Who Made This
This tool was created as an educational project. It's open source and free to use. If you have questions, feedback, or suggestions, feel free to reach out.
Disclaimer
This tool is for educational and informational purposes only. It is not intended to diagnose, treat, or prevent any disease or condition. The information provided should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider or genetic counselor before making decisions based on genetic information.
The developers of this tool are not responsible for any actions taken based on the information provided.