Featured Research

from universities, journals, and other organizations

Families With Severe Form Of Bipolar Disorder Help Scientists Narrow The Search For Disease Genes

Date:
April 1, 2003
Source:
Johns Hopkins Medical Institutions
Summary:
After years of frustrating searches for genes that contribute to mental illness, researchers at Johns Hopkins studying families with a severe form of manic depressive illness, called psychotic bipolar disorder, may be one step closer to finding the genetic underpinnings of both bipolar disorder and schizophrenia.

After years of frustrating searches for genes that contribute to mental illness, researchers at Johns Hopkins studying families with a severe form of manic depressive illness, called psychotic bipolar disorder, may be one step closer to finding the genetic underpinnings of both bipolar disorder and schizophrenia.

"Finding a gene for bipolar disorder is like finding a needle in a haystack, but by focusing our search on families with a distinctive form of the illness we were able to pinpoint a region of the genome where disease genes are likely to be found," said James Potash, M.D., assistant professor of psychiatry at Johns Hopkins and lead author of a report on the study in the April issue of the American Journal of Psychiatry.

Although genes are unlikely to tell the whole story of major psychiatric diseases, the persistent frequency of mental illness in about 1 percent of the global human population, regardless of cultural or ethnic differences, and its tendency to run in families have always pointed to a strong genetic role. "But pinning down that role is complicated by the many variations in symptoms, even within the same family," says Potash. "There are probably many different genes and environmental factors that can cause any given mental illness."

Motivated by previous suggestions that certain broad regions of the DNA sequence, especially on human chromosomes 13 and 22, may contain genes that contribute to both bipolar disorder and schizophrenia, Potash and colleagues focused on those families with the psychotic form of bipolar disorder. Like bipolar disorder, psychotic bipolar disorder is characterized by see-sawing episodes of depression and mania, but it is distinctive because these mood changes often are accompanied by such psychotic symptoms as hallucinations and delusions.

The concept for the new study is that of two slightly overlapping circles, explains Potash. In one circle are all of the genes that contribute to schizophrenia. The other circle has all of the genes that contribute to bipolar disorder, while the intersection of the two circles contains genes that are common to both diseases as well as for psychotic bipolar disorder.

The researchers carefully evaluated and took blood samples from 65 patients with bipolar disorder and from their extended families. They extracted blood cell DNA and scanned it with DNA probes, looking for matching sequences that are more likely to appear in those with mental illness than in those without it. By noting where these markers lay on chromosomes, the researchers were able to narrow in on where the genes were located.

Out of 65 bipolar disorder families studied, the 10 families in which 3 or more members had psychotic bipolar disorder showed strong genetic "linkage" to specific regions on chromosomes 13 and 22. These results differed significantly from those for all 65 families, which showed little or no linkage evidence in these two regions.

"These results confirmed our expectation that genes for the psychotic form of bipolar disorder are likely to be found in the same regions that show linkage to both bipolar disorder as a whole and to schizophrenia," says Potash.

One important implication of the study is that these "overlap genes" may contribute to brain abnormalities that are shared by bipolar disorder and schizophrenia, and could help explain why the same anti-psychotic medications are effective treatments for both diseases, says Potash.

Authors on the report are Potash, Dean MacKinnon, Sylvia Simpson, Francis McMahon, J. Raymond DePaulo, Melvin McInnis, Peter Zandi, Virginia Willour, Tsuo-H. Lan, Yuqing Huo, Dimitrios Avramopoulos, Yin Shugart.

The study was funded by the National Institute of Mental Health, the National Alliance for Research on Schizophrenia and Depression, the Stanley Medical Research Institute, the Dana Foundation, the Alexander Wilson Schweizer Fund, the Affective Disorders Fund and the George Browne Laboratory Fund.

Web sites:

http://www.hopkinsmedicine.org/jhhpsychiatry/master1.htm

http://ajp.psychiatryonline.org/


Story Source:

The above story is based on materials provided by Johns Hopkins Medical Institutions. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins Medical Institutions. "Families With Severe Form Of Bipolar Disorder Help Scientists Narrow The Search For Disease Genes." ScienceDaily. ScienceDaily, 1 April 2003. <www.sciencedaily.com/releases/2003/04/030401072212.htm>.
Johns Hopkins Medical Institutions. (2003, April 1). Families With Severe Form Of Bipolar Disorder Help Scientists Narrow The Search For Disease Genes. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2003/04/030401072212.htm
Johns Hopkins Medical Institutions. "Families With Severe Form Of Bipolar Disorder Help Scientists Narrow The Search For Disease Genes." ScienceDaily. www.sciencedaily.com/releases/2003/04/030401072212.htm (accessed April 16, 2014).

Share This



More Mind & Brain News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cognitive Function: Is It All Downhill From Age 24?

Cognitive Function: Is It All Downhill From Age 24?

Newsy (Apr. 15, 2014) A new study out of Canada says cognitive motor performance begins deteriorating around age 24. Video provided by Newsy
Powered by NewsLook.com
App Fights Jet Lag With The Power Of Math

App Fights Jet Lag With The Power Of Math

Newsy (Apr. 13, 2014) Researchers at the University of Michigan have designed an app to fight jet lag by adjusting your body's light intake. Video provided by Newsy
Powered by NewsLook.com
Treatment Gaps Endangering Cops, Mentally Ill

Treatment Gaps Endangering Cops, Mentally Ill

AP (Apr. 10, 2014) As states slash funding for mental health services, police officers are interacting more than ever with people suffering from schizophrenia and other serious disorders of the mind. The consequences can be deadly. (April 10) Video provided by AP
Powered by NewsLook.com
Teen Drinking Rates Linked To Alcohol Mentions In Pop Music

Teen Drinking Rates Linked To Alcohol Mentions In Pop Music

Newsy (Apr. 9, 2014) A University of Pittsburgh study found pop music that mentions alcohol is linked to higher drinking rates among teens. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins