A new study reveals that 14 psychiatric disorders share genetic roots

An unprecedented genetic analysis conducted on more than one million people revealed that numerous psychiatric disorders share common biological bases. The study, published by Nature, challenges the traditional idea that these conditions are independent of each other.

The researchers found that 14 disorders are grouped into five major genetic categories, opening a new perspective for diagnosis and treatment. According to the study, conditions that were considered completely different show a significant genetic overlap.

Five genetic categories that explain multiple disorders

The team led by Andrew Grotzinger from University of Colorado Boulder observed that people with one diagnosis often receive others recurrently. This prompted an exploration of whether that coexistence had a shared biological origin.

By analyzing millions of genomic data points (among people with different disorders and healthy controls), they identified five major clusters:

• Schizophrenia/Bipolarity
• Internalizing (depression, anxiety, post-traumatic stress)
• Neurodevelopment (ADHD, autism)
• Compulsive (OCD, anorexia)
• Substance use disorders (alcohol, nicotine)

People whose genetic profile matches one of these groups have a higher risk of developing any of the conditions within that same cluster.

Genomic regions that influence multiple diseases

Once the clusters were defined, the team identified 238 genetic regions linked to the shared risk among the different disorders.

A key example is a section of chromosome 11, associated with eight different psychiatric conditions due to its role in dopamine signaling.