Bipolar Disorder (BPD or manic-depressive illness) is one of the most serious of all mental disorders, affecting millions of individuals worldwide. Affected individuals alternate between states of deep depression and mania.

The likelihood of developing bipolar disorder depends in part on the combined, small effects of variations in many different genes in the brain, none of which is powerful enough to cause the disease by itself, a new study shows. However, targeting the enzyme produced by one of these genes could lead to development of new, more effective medications.

Disrupt the gene that regulates the biological clocks in mice and they become manic, exhibiting behaviors similar to humans with bipolar disorder, UT Southwestern Medical Center researchers have found.