Large genetic differences exist between psychiatric disorders, but these differences have rarely been studied. In a new study, Wouter Peyrot, psychiatrist and researcher in our group, compared eight psychiatric disorders based on data from very large numbers of patients. This study was conducted in collaboration with researchers from Harvard University and has been published this week in Nature Genetics.
In this study, a novel method and software enabled the genetic comparison of 40,675 patients with schizophrenia, 20,352 patients with bipolar disorder, 170,756 patients with major depressive disorder, and tens of thousands of patients with five other psychiatric disorders. Thereby, 196 genetic loci were identified with differences across these eight disorders.
An intriguing finding is that certain genes affecting neurite outgrowth and axon regeneration are disrupted more in schizophrenia than in bipolar disorder and major depressive disorder. Interestingly, these findings appear to be in line with the previously described mechanism of synaptic pruning in schizophrenia.
This research promotes the ambitious and important goal of better clinical diagnoses and more disorder-specific treatment of psychiatric disorders. Wouter Peyrot: “We have to be realistic, genetic research is not going to improve the care for our patients overnight. However, given the tremendous recent progress in genetic research, there is broad optimism that genetic research will contribute to clinical care in the future. Both with respect to genetic predictions improving differential diagnosis, as well as with respect to unraveling the biology of psychiatric disorders to hopefully inspire the development of new medications in the future.”