Skip to content

    Bipolar Disorder Health Center

    Font Size

    Many Genes May Affect Bipolar Disorder

    Genes Identified in Study May Lead to New Treatments
    WebMD Health News
    Reviewed by Louise Chang, MD

    May 8, 2007 -- Bipolar disorder, formerly called manic depression, may be influenced by several genes, a new study shows.

    The findings may one day lead to new treatments for bipolar disorder.

    "Treatments that target just a few of these genes or the proteins they make could yield substantial benefits for patients," Francis McMahon, MD, says in a National Institutes of Health (NIH) news release.

    McMahon works for the mood and anxiety disorders program at the National Institute of Mental Health, which is part of the NIH.

    First, McMahon and colleagues screened the genes of 975 people from the U.S., including 412 bipolar disorder patients and 563 people without bipolar disorder.

    The scientists found 80 gene patterns that were more common in the bipolar disorder patients.

    Next, the researchers verified their findings by studying DNA from more than 1,300 Germans, including 679 bipolar disorder patients and 543 people without bipolar disorder.

    Bipolar Disorder's Complex Roots

    No single gene stood out in the DNA studies. The genes identified by McMahon's team were only modestly linked to bipolar disorder.

    "These data suggest that bipolar disorder is ... influenced by many genes, each of small effect," write McMahon and colleagues in Molecular Psychiatry's online edition.

    One of the genes that was more strongly associated with bipolar disorder is the DGKH gene, which makes a protein that is sensitive to the bipolar disorder drug lithium.

    "Lithium is still the primary treatment for bipolar disorder, but DGKH is a promising target for new treatments that might be more effective and better tolerated," says McMahon.

    A person's chance of having bipolar disorder may depend on their bipolar disorder gene profile and environmental factors that interact with genetic risk, the researchers note.

    They add that many of the genes they identified are located in DNA regions that have previously been linked to bipolar disorder and schizophrenia.

    Because gene patterns may vary among different ethnic groups, the researchers only studied people of European descent. Another study is under way to probe the genetic roots of bipolar disorder in other populations, notes the NIH.

    Today on WebMD

    lunar eclipse
    Signs of mania and depression.
    Pills on blank prescription paper
    Learn about this popular bipolar disorder medication.
    serious looking young woman
    Assess your symptoms.
    teen girl in bad mood
    How is each one different?
    Feeling Ups and Downs
    Bipolar or Schizo
    Foods to Avoid
    Man being scolded by his shadow
    lunar eclipse
    depressed man
    young women not speaking
    man talking with therapist