In brief
- Translational Psychiatry, part of the Nature portfolio, publishes the first study comparing the epigenetic footprint of ketamine and MDMA.
- Gene-level aggregation identified 405 associations after ketamine and 346 after MDMA following multiple-comparison correction. No individual CpG site survived that correction; shared genes were not limited to PTPRN2 and SHANK2.
- The study involved 36 people in total, and several authors declared financial ties to organizations and companies in the sector.
DNA methylation is a chemical marker placed on genetic material without altering its sequence. Its relationship with gene regulation depends on genomic context; it is not invariably an on/off switch for gene expression. A team from Arizona State University, the University of Southern California, and the genetic analysis company TruDiagnostic examined what happens to these switches in people who have received ketamine or MDMA in a clinical setting.
How it was measured
The researchers took blood samples from 20 people treated with ketamine and saliva samples from 16 participants in an MDMA trial, both before and after treatment, to compare which positions in the genome had changed state. The BEWAS framework focuses on sites annotated to genes selected for brain relevance; it is not an unrestricted scan of the whole epigenome.
Different paths and shared genes
The paper reports 8,344 nominal CpG associations after ketamine and 11,544 after MDMA, but none individually survived FDR correction. Gene-level aggregation identified 405 and 346 corrected associations, respectively, with 169 and 183 enriched functional sets. Shared genes include PTPRN2, SHANK2 and others; some changed in opposite directions. This does not establish that methylation causes an antidepressant effect. The analysis also pointed to genes linked to immune regulation, a line of inquiry that has been gaining weight in psychiatry for several years.
What it implies
Size matters: 36 people in total. The samples are from blood and saliva, not brain tissue, so extrapolating to what happens in neurons is an inference, not a direct measurement. The study also does not measure whether these changes translate into clinical improvement or how long they last. The authors themselves describe it as a first snapshot. Furthermore, there are declared conflicts of interest in the article that should be kept in mind: the research was funded by two non-profit organizations that promote this field, one of the authors received payment from MAPS or Lykos Therapeutics while working on the trial from which the MDMA samples were taken, and two other authors are employees of the company that performed the genetic analyses. None of this invalidates the data, but it is part of what must be known to weigh them. Even so, the work opens an interesting path: if these substances leave a measurable epigenetic mark in the blood, perhaps one day it will be possible to track their effect without relying solely on questionnaires.
Source
- Semple, M. G., Mennenga, S. E., Smith, R. et al. Brain-targeted epigenetic effects of two emerging psychoplastogens: ketamine & MDMA. Translational Psychiatry, July 11, 2026.
Educational content written from a harm reduction perspective and with respect for individual freedom. It is not a substitute for advice from a healthcare professional and is not intended to encourage or condemn any drug use.
