Among the results, we found a significant reduction in synaptophysin in schizophrenia in the hippocampus (effect size: −0.65, p < 0.01), frontal (effect size: −0.36, p = 0.04), and cingulate cortices (effect size: −0.54, p = 0.02), but no significant changes for synaptophysin in occipital and temporal cortices, and no changes for SNAP-25, PSD-95, VAMP, and syntaxin in frontal cortex. This evidence concerns the gene DLG4 and schizophrenia.