Genetic study explains overlap among common psychiatric conditions
Large-scale genetic analysis across disorders
An international study has identified extensive genetic overlap across 14 psychiatric disorders, helping explain why multiple diagnoses are common over a person’s lifetime. The research, published on December 10 in Nature, analyzed genetic data from more than 6 million individuals, including over 1 million people with a childhood or adult psychiatric disorder and about 5 million individuals without a diagnosis. The study is the latest effort from the Psychiatric Genomics Consortium Cross-Disorder Working Group, co-chaired by Kenneth Kendler, a professor in the Department of Psychiatry at Virginia Commonwealth University School of Medicine, and Jordan Smoller, a professor in the Department of Psychiatry at Harvard Medical School.
Five genetically related disorder groups
Using multiple analytical approaches, the researchers identified 428 genetic variants linked to more than one disorder and 101 chromosomal regions where shared variants were concentrated. Statistical modeling showed that the 14 conditions clustered into five genetically related groups covering compulsive disorders, internalizing disorders, neurodevelopmental disorders, schizophrenia and bipolar disorder, and substance use disorders. Major depression, anxiety disorders, and post-traumatic stress disorder showed especially strong overlap, with about 90% of genetic risk shared across these conditions. Schizophrenia and bipolar disorder shared roughly two thirds of their genetic markers.
Related: Researchers uncover key mechanism linking cellular stress to Alzheimer’s progression
Implications for psychiatric research and care
According to the researchers, disorders with greater genetic overlap also showed similarities in when shared genes were active during human development and which brain cell types were involved. Internalizing disorders were more closely linked to genes expressed in oligodendrocytes, while schizophrenia and bipolar disorder were more associated with genes expressed in excitatory neurons. The findings provide a genetic framework for understanding comorbidity in psychiatry and may inform future research into treatments for conditions that frequently occur together.
Source: VCU
Category: Education
