Emerging evidence suggests Major Depressive Disorder (MDD) may be detectable through shared molecular changes in brain and blood. Multiomic data reveals overlapping genetic and epigenetic signatures that could pave the way for clinically useful biomarkers.
This systematic review, analyzing 54 studies, found 744 differentially expressed genes altered in the same direction in brain and blood. Additionally, 544 differentially methylated genes showed similar alterations across both tissues. Identified hub genes converged on developmental, inflammatory, transcriptional, apoptotic, and mitochondrial pathways, indicating coordinated molecular dysregulation detectable across tissues.
The identification of these overlapping signatures suggests MDD may have measurable peripheral biomarkers reflecting central nervous system pathology. Such biomarkers could support earlier diagnosis, enable phenotypical stratification, and inform precision medicine approaches. Future research aims to clarify causal mechanisms with cell type-specific multiomic analyses.