Binnen en buiten de psychiatrie wordt veel gediscussieerd over het belang en vooral over de beperkingen van de diagnostische classificaties waarmee dagelijks wordt gewerkt.1 Ook de recentste versie van de ‘Diagnostic and Statistical Manual of Mental Disorders’ (DSM-5) baseert diagnostische categorieën op afspraken over het voorkomen van combinaties van veelal subjectief waargenomen symptomen.
In clinical practice, psychiatric patients often receive two or even more diagnoses. Also, psychiatric diagnoses commonly change over time. Biomarkers to facilitate a differential diagnosis would be helpful, but the search to find such help has largely been in vain. The situation is different in neurology, since diagnoses do not commonly change and comorbidity is not the rule. Furthermore, in this field biomarkers for a differential diagnosis are readily available. The results from the recent genome-wide analysis by the BrainSTORM consortium published in Science (2018) have shed light on this inequality by showing that mental, but not neurological, disorders have largely overlapping genetic backgrounds. This finding suggests that the substrates of mental disorders, or at least their vulnerabilities, are to a large extent similar. The search for biomarkers in psychiatry should therefore continue in a generalised way, i.e. we should investigate common vulnerabilities for mental disorders in order to provide early supportive and protective measures to prevent any type of mental illness.
Conflict of interest and financial support: potential conflicts of interest have been reported for this article. ICMJE forms provided by the authors are available online along with the full text of this article.