Featured Research

from universities, journals, and other organizations

Additional Genetic Influence For Alzheimer's Disease Confirmed

Date:
August 21, 1998
Source:
University Of Toronto
Summary:
An additional genetic influence for Alzheimer's disease has been confirmed in families with a high incidence of the disorder, according to a study published in the August 19 issue of the Journal of the American Medical Association.

An additional genetic influence for Alzheimer's disease has been confirmed in families with a high incidence of the disorder, according to a study published in the August 19 issue of the Journal of the American Medical Association.

The study confirms the existence of an Alzheimer's disease susceptibility gene on chromosome 12. The findings also imply there's at least one other gene associated with a risk or susceptibility to late-onset Alzheimer's disease that has not yet been identified.

The 46 chromosomes normally present in every cell of the human body carry hereditary factors encoded in what's estimated to be between 75,000 to 100,000 unique genes. "Defining the gene associated with a family's susceptibility to Alzheimer's will eventually provide researchers with new and otherwise unattainable insight into how the disease occurs," says lead investigator Professor Peter St. George-Hyslop, director of the Centre for Research in Neurodegenerative Diseases at the University of Toronto."

"Although we don't yet know where the Alzheimer's susceptibility gene is precisely located on chromosome 12, there are a number of genes on this chromosome which might be associated with Alzheimer's disease," says St. George-Hyslop. "Our preliminary studies suggest that it is probably not either of two genes on chromosome 12 that have recently been implicated in Alzheimer's disease."

The researchers collected DNA samples from 53 families with two or more individuals affected by Alzheimer's disease. This involved 173 people with Alzheimer's disease and 146 nondemented relatives. Once the samples were checked and showed the Alzheimer's disease was not due to mutations in the known genes, the investigators then studied the samples for a series of DNA markers located on chromosome 12.

"We were able to show these markers were associated with Alzheimer's disease in a family," said co-principal investigator Dr. Lindsay Farrer, a professor of medicine and chief of the genetics program at Boston University School of Medicine. "The next step will be to study many more families in order to identify the exact region. Once we have narrowed the region to a small DNA segment, we can then focus our attention on the genes contained in this segment."

"This type of research -- first defining genetic risk factors and then defining how these genes cause Alzheimer's disease -- provides a strong basis for attempts to develop treatments and preventions based on a rational understanding of the disease rather than simply trying different drugs to see if they work," explains St. George-Hyslop. "There are many more years of hard work ahead of us."

Unlike genetic diseases such as cystic fibrosis and Huntington's disease in which the presence of the gene for these disorders consistently results in having the disease, Alzheimer's disease is complex and involves multiple factors, much like cardiovascular disease. "It's too early to say whether or not the gene on chromosome 12 can be used to predict a person's susceptibility to the disease," notes Farrer.

Alzheimer's disease is a neurodegenerative disorder that is characterized by pervasive and progressive memory and cognition loss, accompanied by physical changes in the brain such as a loss of neurons, deposits of extracellular amyloid plaque and tangles' of fibres between neurons. Epidemiological and molecular genetic data suggest that although there are likely multiple factors influencing the cause of Alzheimer's, genetic factors play a prominent role in many cases.

The research was supported by grants through the Medical Research Council of Canada, The Canadian Genetic Diseases Network, The Alzheimer Association of Ontario, The Howard Hughes Medical Research Foundation, the EJLB Foundation, Telethon and the National Institutes of Health.


Story Source:

The above story is based on materials provided by University Of Toronto. Note: Materials may be edited for content and length.


Cite This Page:

University Of Toronto. "Additional Genetic Influence For Alzheimer's Disease Confirmed." ScienceDaily. ScienceDaily, 21 August 1998. <www.sciencedaily.com/releases/1998/08/980821085738.htm>.
University Of Toronto. (1998, August 21). Additional Genetic Influence For Alzheimer's Disease Confirmed. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/1998/08/980821085738.htm
University Of Toronto. "Additional Genetic Influence For Alzheimer's Disease Confirmed." ScienceDaily. www.sciencedaily.com/releases/1998/08/980821085738.htm (accessed July 24, 2014).

Share This




More Mind & Brain News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Newsy (July 23, 2014) An 8-year-old boy helped his younger brother, who has a rare genetic condition that's confined him to a wheelchair, finish a triathlon. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Do Obese Women Have 'Food Learning Impairment'?

Do Obese Women Have 'Food Learning Impairment'?

Newsy (July 18, 2014) Yale researchers tested 135 men and women, and it was only obese women who were deemed to have "impaired associative learning." 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