Scientists have confirmed a genetic link between bipolar disorder and schizophrenia, according to a study published Monday.

The study, published in the journal Nature Genetics, has found 11 variations in specific parts of the genetic code that had been associated with schizophrenia.  The study confirms that these variations contribute to the risk of an individual developing bipolar disorder as well.

The study is an international effort from experts from more than 20 nations including scientists from Australia. University of NSW psychiatrist Philip Mitchell, who led the Australian research team, says the study will help researchers better understand the disease and will provide insight for future treatments.

"There are six or seven different medications used at the moment for bipolar disorder, but they still have very marked limitations and most people continue to have frequent episodes of illness that stop them progressing in their careers or maintaining relationships, and some people still attempt suicide," Mitchell said.

"Identifying the genes will eventually give new targets for drug development. Overall, it's a very important and exciting study."

Newcastle University Professor Rodney Scott added that the study is the first time a concrete link has been found between schizophrenia and bipolar disorder.

"Now this genetic study has identified two genetic loci that are common in both bipolar disease and schizophrenia," Scott said.

"This certainly has implications with respect to our future understanding of what the mechanisms are at the cellular level that give rise to the two diseases. At this point in time we don't know what all the different genetic factors are that result in schizophrenia."

The researchers used high-speed genetic number crunching to identify common patterns between patients with schizophrenia and bipolar disorders. Two genetic variations were found in both sets of patients: one that encoded for a part of a channel that allows calcium ions to pass through cell membranes, and another that programmed a particular protein to be expressed on a cell's surface.

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