Shared Genetics Explain Why Mental Health Disorders Often Overlap

A major international genetics study has found that many psychiatric disorders are closely linked at a biological level, helping explain why people are often diagnosed with more than one mental health condition. Published in Nature, the research analyzed genetic data from more than six million individuals, making it the most comprehensive study to date on shared genetic risk across mental illnesses.

Led by the Psychiatric Genomics Consortium’s Cross-Disorder Working Group, scientists examined 14 psychiatric conditions and discovered they cluster into five broad genetic groups rather than existing as separate diseases. The analysis identified hundreds of genetic variants and multiple chromosomal regions that contribute to more than one disorder.

Some conditions showed particularly strong overlap. For example, depression, anxiety, and post-traumatic stress disorder shared most of their genetic risk, while schizophrenia and bipolar disorder also displayed substantial commonality. These shared genetic patterns help clarify why psychiatric diagnoses frequently coexist and may support future improvements in diagnosis, classification, and treatment of complex mental health conditions.

08-01-2026