The international ‘Brainstorm Consortium’ has conducted the first ever global study, finding a significant correlation of certain brain disorders to be genetically linked.
Through analysing the genome of 1.1 million patients with psychiatric and brain disorders, the study has shown that certain psychiatric disorders such as anorexia, anxiety and depression have mainly been diagnosed phenotypically.
There are many factors affecting brain disorders
Andreas Karwautz, child and adolescent psychiatrist at MedUni Vienna’s Department of Child and Adolescent Psychiatry and co-author of the study explains: “There is no such thing as ‘simple’ depression or ‘simple’ anorexia that does not exhibit symptoms of other mental disorders.”
“A diagnosis is always heterogeneous.”
Comprising several working groups from Harvard University and Massachusetts Institute of Technology in the US, the genomic data from around 265,000 psychiatric and neurological patients has been extensively analysed, as well as 785,000 healthy individuals.
For the purposes of the recent study, the common hereditary factors of 15 neurological diseases and 10 psychiatric diseases were analysed, with the main aim being to investigate whether there is a correlation between disorders with certain genetic features.
What were the main findings of the study?
One key aspect taken into account was that psychiatric and neurological disorders were each considered as an individual group and then in comparison to each other.
The main finding was that a few psychiatric disorders such as schizophrenia, depression, bipolar and anxiety have significant genetic commonalities, increasing the risk of patients who develop one disorder also developing the correlated disorder.
On the other hand, depression and anxiety disorder are closely related genetically, even if their symptoms are very different.
The same applies to anorexia, obsessive-compulsive disorder (OCD), schizophrenia and bipolar disorder.
Another key aspect indicates there is generally a greater genetic difference between neurological diseases within their own group.
Significant overlaps to specific genetic tendencies
The study, therefore, showed that there are overlaps when it comes to specific genetic tendencies, thereby casting doubt upon traditional diagnostic classifications.
Karwautz explains: “This genome analysis, which for the first time involved statistically significant case numbers, forms a good basis for improving the psychiatric classification models with the aid of well-founded neurobiological diagnostics.”
“As a researcher, I am delighted that my work at MedUni Vienna has enabled me to contribute to this global endeavour.”