Bipolar Disorder Health Center

Scientists are learning about the possible causes of bipolar disorder. Most scientists agree that there is no single cause. Rather, many factors likely act together to produce the illness or increase risk.

Bipolar disorder tends to run in families, so researchers are looking for genes that may increase a person's chance of developing the illness. Genes are the "building blocks" of heredity. They help control how the body and brain work and grow. Genes are contained inside a person's cells that are passed down from parents to children.

Children with a parent or sibling who has bipolar disorder are four to six times more likely to develop the illness, compared with children who do not have a family history of bipolar disorder. However, most children with a family history of bipolar disorder will not develop the illness.

Genetic research on bipolar disorder is being helped by advances in technology. This type of research is now much quicker and more far-reaching than in the past. One example is the launch of the Bipolar Disorder Phenome Database, funded in part by NIMH. Using the database, scientists will be able to link visible signs of the disorder with the genes that may influence them. So far, researchers using this database found that most people with bipolar disorder had:

• missed work because of their illness
• other illnesses at the same time, especially alcohol and/or substance abuse and panic disorders
• been treated or hospitalized for bipolar disorder.
• the researchers also identified certain traits that appeared to run in families, including:
• history of psychiatric hospitalization
• co-occurring obsessive compulsive disorder (OCD)
• age at first manic episode
• number and frequency of manic episodes.

Scientists continue to study these traits, which may help them find the genes that cause bipolar disorder some day.