People with major depressive disorder or schizophrenia have been found to have lower levels of the synaptic protein “SNAP-25” in their cerebrospinal fluid. These were the findings of a study by University Medicine Halle that included more than 200 participants. Even though SNAP-25 cannot yet be used to make reliable diagnoses, the findings suggest that protein biomarkers could one day play an important role in the diagnosis and monitoring of psychiatric disorders. The findings were published in the journal BMJ Mental Health.