WebMD Medical News
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
The scientists found 80 gene patterns that were more common in the bipolar
Next, the researchers verified their findings by studying DNA from more than
1,300 Germans, including 679 bipolar disorder patients and 543 people without
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
"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
SOURCES: Baum, A. Molecular Psychiatry, May 8, 2007; online edition.
News release, National Institutes of Health. News release, Molecular
Here are the most recent story comments.View All
The views expressed here do not necessarily represent those of WETM 18 Online
The Health News section does not provide medical advice, diagnosis or treatment. See additional information.