One of the major benefits of biobanking is the ability to safely collect and store large numbers of biological samples. This allows researchers to generate large datasets to study the genetic cause of various diseases. The Brainstorm Consortium uses large datasets to investigate the causes of psychiatric and neurodegenerative diseases. The Brainstorm Consortium comprises researchers from across the world, including scientists from Harvard and Stanford Universities in the US, and from the Universities of Oxford and Cambridge in the UK.
The Brainstorm Consortium recently analyzed an enormous data set with phenotypic and genetic data from over 1,190,000 individuals. They were looking for any overlap in the genetic risk factors for 25 different brain disorders, as well as assessing the heritability of those diseases. This work was published in the journal Science (1).
We know from previously published twin and epidemiological studies that certain brain disorders occur more commonly together, called comorbidity. Comorbid brain disorders include bipolar disorder and migraine (2), and epilepsy and autism spectrum disorder (ASD) (3). Furthermore, a number of genome-wide association studies (GWAS) have shown that psychiatric disorders including schizophrenia, depression and bipolar disorder can have common genetic risk variants. That means that people with certain genetic variants are at a higher risk of developing these psychiatric disorders.
Brainstorm Consortium Finds Genetic Link in Psychiatric Disorders
Brainstorm Consortium researchers collected and quality-controlled multiple sets of GWAS meta-analysis data for 25 brain disorders. They compared genetic risk factors for each disorders. Consortium scientists found significant correlation between genetic risk factors for multiple psychiatric disorders, including attention deficit hyperactivity disorder (ADHD), bipolar disorder, depression and schizophrenia.
The major disorders schizophrenia, bipolar disorder, depression, anxiety and ADHD were all genetically linked to each other. Furthermore, schizophrenia had significant genetic correlation with almost all psychiatric disorders included in this study. Depression also positively correlated with all other psychiatric disorders.
This means that many of the most common psychiatric disorders could have common genetic causes and follow common disease progression at the cellular and molecular level.
Brainstorm Consortium Finds Neurological Disorders are Genetically Unique
In contrast, neurological disorders such as Parkinson’s disease, Alzheimer’s disease, multiple sclerosis and epilepsy showed limited similarities in genetic risk factors. This means that, unlike psychiatric disorders, neurological diseases are likely to be genetically unique and have different molecular causes. One notable exception was a genetic link between migraine and epilepsy.
Conclusion
This is a robust gene association study with a very large dataset. The results of this study support previously published data showing that a number of psychiatric disorders are genetically linked. The Brainstorm Consortium scientists concluded that different psychiatric disorders may have similar genetic causes. This result needs further investigation but may influence how psychiatric disorders are diagnosed and treated.
References
- The Brainstorm Consortium. Analysis of shared heritability in common disorders of the brain. Science. 2018.
- Hirschfeld et al. Screening for bipolar disorder in the community. J. Clin. Psychiatry. 2003.
- Lo-Castro et al. Epilepsy associated with autism and attention deficit hyperactivity disorder: Is there a genetic link? Brain Dev. 2014
