Navigation Links
Gene Variant May Hike Women's Risk of Alzheimer's
Date:1/12/2009

Men can carry the variation as well, study finds

MONDAY, Jan. 12 (HealthDay News) -- Scientists have discovered a gene variant on the X chromosome that appears to increase the risk of developing Alzheimer's disease.

The risk was most pronounced in women with the variant on both X chromosomes, although both women and men with just one variant of the gene were also at greater risk.

"What you have in a nutshell is the first study showing a gene on the X chromosome and the first sex-specific effect [for Alzheimer's]," said Dr. Steven Younkin, senior author of the paper published online Jan. 11 in the journal Nature Genetics. "It does not mean women are at increased risk for Alzheimer's."

Although the presence of the mutation offers strong evidence of a heightened risk, further research needs to be done to determine how big of a risk, added Younkin, who is the George M. Eisenberg professor of neuroscience at the Mayo Clinic College of Medicine in Jacksonville, Fla.

Dr. Anton Porsteinsson, director of the Alzheimer's Disease Care, Research and Education Program and the Memory Disorders Clinic at the University of Rochester School of Medicine, called the finding intriguing.

"To me, the fact that it's X-linked is intriguing because of the fact that there are more women than men with Alzheimer's disease," he said.

According to background information in the paper, late-onset Alzheimer's disease is the most common cause of dementia in older people, affecting about 10 percent of those aged 65 or over.

A mutation in the APOE 4 gene is the only genetic risk factor that has been "solidly" linked to the risk of late-onset Alzheimer's, Porsteinsson said. Other genes have been linked to early onset disease.

"The effort to find additional genetic variants has been difficult," Younkin said.

For the study, Younkin and his colleagues scanned hundreds of thousands of genes in 844 people with Alzheimer's disease and 1,255 healthy people who served as "controls."

There was nothing genetic in the first pass that the researchers could say unequivocally was associated with Alzheimer's disease.

But a second pass, this one on even more patients and controls, uncovered a strong association between a mutation on the PCDH11X gene and Alzheimer's disease.

"It was significant enough to convince us we had something real," Younkin said.

The findings were given added weight because the researchers examined autopsies on participants who had died to confirm the diagnosis of Alzheimer's. Clinical diagnoses are about 90 percent accurate anyway, Porsteinsson said.

Women with two copies of the gene had a 75 percent increased risk for Alzheimer's. Women with only one copy of the gene had a 26 percent increased risk, while men with one copy had an 18 percent increased risk.

The gene is part of a family of genes linked with the nervous system and are involved in cell adhesion.

"We're basically looking at a finding that seems to encode a gene that has something to do with central nervous system development," Porsteinsson said. "And Alzheimer's is ultimately a central nervous system disease."

It's unclear how the gene may actually work to increase the risk of Alzheimer's. Once that is known, however, the search for new treatments could be accelerated, the researchers said.

"It's trite but true -- the reason we all search for genes is that every one opens a door to identify people at risk, and every one opens a door to identify potential therapies if we can understand how it works," Younkin said.

But first, these findings need to be replicated. "This just means a lot of work ahead," Porsteinsson said.

More information

To learn more, visit the Alzheimer's Association.



SOURCES: Steven Younkin, M.D., Ph.D., George M. Eisenberg professor of neuroscience, Mayo Clinic College of Medicine, Jacksonville, Fla.; Anton Porsteinsson, M.D., director, Alzheimer's Disease Care, Research and Education Program, and director, Memory Disorders Clinic, and associate professor of psychiatry, University of Rochester School of Medicine, Rochester, N.Y.; Jan. 11, 2009, Nature Genetics, online


'/>"/>
Copyright©2009 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Scientists demonstate link between genetic variant and effectiveness of smoking cessation meds
2. Scientists discover genetic variant associated with prostate cancer in African Americans
3. Gene Variant Doubles Risk of Prostate Cancer in Black Men
4. Gene Variant Tied to More Aggressive Prostate Cancer
5. Gene variant linked to moderated symptoms of beta-thalassemia
6. Gene variant predicts medication response in patients with alcohol dependence
7. Gene Variants Can Predict Threat of Heart Disease
8. Gene Variants Linked to Lung Cancer Identified
9. Gene Variant Protects Black Heart Failure Patients
10. Gene Variant Boosts Risk for Stress-Related Ischemia
11. Gene Variant Boosts Risk of Severe Diabetic Eye, Kidney Diseases
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... June 25, 2016 , ... "With 30 hand-drawn hand ... project," said Christina Austin - CEO of Pixel Film Studios. , ProHand Cartoon’s ... within Final Cut Pro X . Simply select a ProHand generator and drag ...
(Date:6/25/2016)... ... June 25, 2016 , ... Conventional wisdom preaches the benefits of moderation, ... the latter, setting the bar too high can result in disappointment, perhaps even self-loathing. ... toward their goal. , Research from PsychTests.com reveals that behind the ...
(Date:6/24/2016)... ... 2016 , ... The Pulmonary Hypertension Association (PHA) learned during ... two significant new grants to support its work to advance research and patient ... recognizing patients, medical professionals and scientists for their work in fighting pulmonary hypertension ...
(Date:6/24/2016)... TX (PRWEB) , ... June 24, 2016 , ... People ... part in Genome magazine’s Code Talker Award, an essay contest in which patients and ... an award to be presented at the 2016 National Society of Genetic Counselors (NSGC) ...
(Date:6/24/2016)... ... , ... National recruitment firm Slone Partners is pleased to announce ... experience, as Vice President of North American Capital Sales at HTG Molecular . ... sales team in the commercialization of the HTG EdgeSeq system and associated reagents in ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... June 24, 2016 Research ... "Structural Electronics 2015-2025: Applications, Technologies, Forecasts" ... In-Mold Electronics, Smart Skin, Structural Health ... Structural electronics involves electronic and/or electrical ... structures, replacing dumb structures such as vehicle bodies ...
(Date:6/24/2016)... Calif. , June 24, 2016  American Respiratory Labs (ARL), ... is now able to perform sophisticated lung assessments in patients, homes, ... , Inc. Patients are no longer limited to ... EasyOne PRO ® , ARL patients like Jeanne R. of ... in the comfort of her own home. ...
(Date:6/24/2016)... , June 24, 2016   Pulmatrix, Inc ... company developing innovative inhaled drugs, announced today that it ... Russell Investments reconstituted its comprehensive set of U.S. ... "This is an important milestone for Pulmatrix," said ... increase shareholder awareness of our progress in developing drugs ...
Breaking Medicine Technology: