Using advanced statistical methods, the team grouped the disorders into five genetically related categories, revealing particularly strong overlap between conditions such as depression, anxiety and post-traumatic stress disorder, as well as between schizophrenia and bipolar disorder. These shared genetic patterns were also associated with similar biological processes in the brain, including the timing of gene activity during development and the types of brain cells involved.
The findings provide a stronger biological basis for understanding psychiatric diagnoses and may support future efforts to develop treatments that better reflect the underlying causes of mental illness, particularly for people with complex or multiple diagnoses.
Reflecting on the collaborative nature of the research, Kendler said, “I feel very proud to be a part of this effort. This work really shows that we gain more for our field and for those suffering from mental illness when we come together to tackle these scientific challenges.”