Bipolar Disorder Manic Gene Discovered
September 2, 2012

Gene Associated With Bipolar Manic Episodes Discovered By Researchers

redOrbit Staff & Wire Reports - Your Universe Online

Researchers from the University of Bonn and the Central Institute of Mental Health (CIMH) in Mannheim claim to have discovered the gene responsible for causing the manic episodes associated with bipolar disorder.

The scientists studied patient data and animal models, and were able to determine that the NCAN gene, which is believed to be involved in the modulation of cell adhesion and migration, is responsible for the restlessness, euphoria, and other feelings associated with the manic cycle of the psychiatric mood disorder, the university explained in a September 1 statement.

Dr. Markus M. Nöthen, Director of the Institute of Human Genetics at the University of Bonn, and colleagues evaluated genetic data and the associated descriptions of symptoms from more than 1,200 patients, each of whom demonstrated different ratios between the manic and depressive phases of bipolar disorder. Using those subjects' clinical data, they were able to discover which symptoms were closely related to the gene in question.

"It has been known that the NCAN gene plays an essential part in bipolar disorder," Nöthen said in a statement. "But until now, the functional connection has not been clear."

They also studied mice in which the gene had been "knocked out," and a team led by Dr. Andreas Zimmer, Director of the university's Institute of Molecular Psychiatry, said that the rodents exhibited no depressive behavior, only manic ones. They were more active than the control group and more likely to engage in risky and reward-seeking behavior, such as unrestrained consumption of a sugar solution provided by the researchers, they explained.

Those mice were then presented with lithium, a standard treatment course for humans, and their hyperactive behavior was all but eliminated, Zimmer said. Since the reaction of both mice and humans to the lithium were identical, the researchers report that those regarding the NCAN gene were as well, as previous work has demonstrated that "knocking out the NCAN gene results in a developmental disorder in the brain due to the fact that the production of the neurocan protein is stopped," the press release said.

The researchers say that they want to further explore the connection between the NCAN gene and bipolar disorder, and are hopeful that their work could lead to new therapies to treat the condition. As CIMH professor Dr. Marcella Rietschel said, their work is "a great prerequisite for advancing the development of new drugs for mania therapy."