Oct 11 2009
For the first time, sufferers of schizophrenia and bipolar disorder are being brought together in a major new study investigating the diseases' common genetic causes and manifestations.
Researchers from the University of New South Wales (UNSW) believe the study will challenge the traditional classification of schizophrenia and bipolar disorder as separate diseases.
They hope the results will aid the early detection of a cognitive vulnerability to psychosis in adolescence, facilitating early intervention and the development of drug treatments that can be personalised according to genotype.
Recent molecular genetic and epidemiological studies in Sweden and the US have suggested that the disorders share some common genetic susceptibility, but the results have not been definitive in determining which genes are shared and what they code for.
"The international diagnostic manual for the classification of psychiatric disorders is currently being revised and it's being considered as to whether schizophrenia and bipolar disorder should be grouped together. It's very controversial," said study leader Dr Melissa Green, from UNSW's School of Psychiatry.
"There's not been enough evidence so far to support that change - this study will provide good quality evidence on this issue," she said.
Dr Green and her team will integrate data from genetics, functional neuroimaging, cognitive testing and physiological measurements to pinpoint shared genetic susceptibility to the disorders, which may manifest in common cognitive and frontal brain dysfunctions.
"This is one of the only dedicated studies to provide multi-level biological data on both schizophrenia and bipolar disorder. Other researchers have looked at genetics of cognition and brain function in schizophrenia and bipolar disorder separately, but very little research has examined the two diseases together," she said.
"We've spent over 100 years trying to work out what's causing schizophrenia and bipolar disorder, and many people believe that maintaining these conditions as distinct diseases has been holding us back," Dr Green said.
"Already some medications are shared across the two disorders, and are aimed at treating overt psychotic symptoms. With more information, new drugs could be developed to improve the enduring cognitive deficits as well."
Dr Green was recently named as an Australian Research Council Future Fellow, with her project attracting close to $700,000 funding over four years from the federal government. The study is being conducted in collaboration with researchers at the Schizophrenia Research Institute, the Black Dog Institute, the Prince of Wales Medical Research Institute, and Leiden University, The Netherlands.
About the study:
The study requires large samples of patients with schizophrenia, bipolar I disorder, schizoaffective disorder, and healthy control participants (at least 300 total participants)
It will test the hypotheses (1) that shared genetic susceptibility to schizophrenia and bipolar disorder may manifest in common cognitive deficits / frontal brain dysfunction, and (2) that differences between the conditions in cognitive/emotional manifestations of shared genetic susceptibility may be influenced by differences in stress reactivity (hypothalamic-pituitary-adrenal -HPA - function) between the two disorders.
The research will use multidisciplinary techniques - genetics, functional neuroimaging, cognitive testing, physiological measurements (cortisol in saliva) - to obtain data that can be integrated to test the study hypotheses.
Participants:
For recruitment purposes, participants need to be aged 18-60yrs, free of other neurological conditions (eg. epilepsy), English speaking, and with no current substance abuse.
For more information contact Dr Melissa Green (Tel. 02 9382 8382)
Media contact: Dr Melissa Green 02 9382 8382: Steve Offner, UNSW Media 02 9385 8107 or 0424 580 208
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