CAMH scientists have discovered rare genetic changes that may be responsible for the onset of schizophrenia. Several of these same genetic lesions had previously been found to have causal links to autism spectrum disorder (ASD). This discovery gives new support to the notion that multiple rare genetic changes may contribute to schizophrenia and other brain disorders.
This discovery suggests that clinical DNA testing may be useful in demystifying one of the most complex and stigmatized human diseases. The study is published in the current issue of Human Molecular Genetics, and was funded by the Canadian Institutes of Health Research (CIHR).
"We found a significant number of large rare changes in the chromosome structure that we then reported back to the patients and their families," said Dr. Anne Bassett, Director of CAMH's Clinical Genetics Research Program and Canada Research Chair in Schizophrenia Genetics and Genomic Disorders at the University of Toronto. "In total, we expect that up to eight per cent of schizophrenia may be caused in part by such genetic changes -- this translates to roughly one in every 13 people with the illness."
The research team also developed a systematic approach to the discovery and analysis of new, smaller rare genetic changes leading to schizophrenia, which provides dozens of new leads for scientists studying the illness. "We were able to identify smaller changes in chromosome structure that may play an important role in schizophrenia - and that these often involve more than one gene in a single person with the illness," added Dr. Bassett, who is also a Clinician Scientist in the Campbell Family Mental Health Research Institute.
"Moving forward, we will be able to study common pathways affected by these different genetic changes and examine how they affect brain development. The more we know about where the illness comes from, the more possibilities there will be for the development of new treatments."