A collaboration, led by scientists at the Garvan Institute of Medical Research and the University of New South Wales (UNSW) in Sydney, has discovered the first risk gene specifically for bipolar disorder, also known as manic-depressive illness. This means that people who have a particular form of this gene are twice as likely to develop the disease.
Lead author, Dr Ian Blair, says: "We are the first group in the world to take a multi-faceted approach to identify a bipolar risk gene - we used a number of families, unrelated patients, and therapeutic drug mouse models. Each of these three lines of investigation led us to a gene called FAT."
Contributing author Professor Phil Mitchell, Head of Psychiatry at UNSW, says: "Over the last twenty years we have collected blood samples from 67 families right across Australia. This amounts to hundreds of family members (904), some of whom are spread across four generations. This was a strong starting point in our hunt for a Bipolar gene."
"We know that the FAT gene codes for a protein that is involved in connecting brain cells together, what we need to do now is find out exactly how it contributes to the increased risk of bipolar disorder," explains Dr Blair.
While other scientists have found genes associated with Bipolar, most of them haven't stood up to scrutiny. The Sydney discovery has been verified in four independent study groups: two in the UK, one in Australia, and one in Bulgaria.
Bipolar disorder is a major psychiatric illness affecting around two people in every 100. Tragically, around one in six people suffering from the condition will commit suicide.