An international study led by Trinity researchers, along side the Broad Institute at Massachusetts Institute of Technology (MIT) and Harvard University, has determined that psychiatric disorders such as schizophrenia and bipolar disorder share many genetic variants, according to a study published today in the journal, Science.
The study, led by Professor in Psychiatry, Aiden Corvin of Trinity, and Dr. Ben Neale of MIT and Harvard, focused on the genetic basis of various psychiatric disorders at a scale that surpasses previous research completed on the subject. The study included researchers from more than 600 institutions worldwide.
The genetic overlap of 25 disorders were analysed, with 265,218 patients and 784,643 controls. The results showed that psychiatric disorders may have important molecular similarities, in contrast with neurological disorders such as Parkinson’s or Alzheimer’s which appear to be more distinct from one another and from the psychiatric disorders. An exception to this is migraine, which was genetically correlated to ADHD, major depressive disorder, and Tourette syndrome.
In particular, a widespread genetic overlap was found between attention-deficit hyperactivity disorder (ADHD), bipolar disorder, major depressive disorder, and schizophrenia. The results also suggested a strong overlap between anorexia nervosa and obsessive-compulsive disorder (OCD), and OCD and Tourette syndrome.
In addition, the study found that genetic factors associated with certain psychiatric disorders such as anorexia, autism, bipolar, and OCD, were significantly correlated with higher childhood cognitive measures, which include a higher number of years in education and college degree attainment. On the other hand, neurological disorders, such as Alzheimer’s and stroke, were negatively correlated with these same cognitive measures.
The research was funded in part by the National Institutes of Health (NIH), the Orion Farmos Research Foundation, and the Fannie and John Hertz Foundation. It is considered a breakthrough in the study of the molecular basis of psychiatric disorders. The results obtained do not accurately reflect current diagnostic categories as it had not been previously possible to examine the subject. Further studies can define the presentation of the disorder in a patient, and allow for better selection and treatment of the patients.
Professor Corvin remarked on the significance of the study, saying that “our work suggests that mechanisms in the brain can cause overlapping symptoms and this brings us a step closer to understanding how to diagnose and treat these conditions more effectively.”
Dr. Ben Neale adds: “If we can uncover the genetic influences and patterns of overlap between different disorders, then we might be able to better understand the root causes of these conditions— and potentially identify specific mechanisms appropriate for tailored treatments.”
Professor Corvin’s team is now pursuing a deeper study of the genome and its connection with psychiatric conditions. The work is co-funded by Science Foundation Ireland (SFI) and the US National Institute of Mental Health (NIMH).