Featured Research

from universities, journals, and other organizations

Gene Linked To Aggressive 'Wet' Age-related Macular Degeneration

Date:
November 27, 2006
Source:
Yale University
Summary:
A gene variant that increases the risk of developing the aggressive "wet" form of age-related macular degeneration, the most common cause of blindness in people over age 50, is reported in two recent articles in Science by researchers at Yale School of Medicine.

A gene variant that increases the risk of developing the aggressive "wet" form of age-related macular degeneration (AMD), the most common cause of blindness in people over age 50, is reported in two recent articles in Science by researchers at Yale School of Medicine.

Related Articles


AMD causes light-sensitive cells in the retina to break down, resulting in progressive loss of central vision. Of the two forms of AMD, the "dry" is more common than the "wet" form. Wet macular degeneration can rapidly lead to blindness, while the dry AMD progresses more slowly.

Last year, Josephine Hoh, associate professor in the Departments of Epidemiology & Public Health and Ophthalmology at Yale and senior author on one of the two new studies, identified a gene for dry AMD and found that both wet and dry AMD are associated with a variant in the complement factor H (CFH) gene on chromosome 1.

Hoh now reports they have found a single nucleotide polymorphism (SNP)--a one-base change in the sequence--of the regulatory part of the HTRA1 gene on chromosome 10 that leads to greatly increased risk of developing the wet form of AMD.

According to Hoh, buildup of abnormal blood vessels in Caucasian patients is compounded by development of large waste deposits called drusen. Chinese patients, she said, develop little to no drusen and progress directly to wet AMD. This study demonstrates that these two major genes, CFH and HTRA1, in two different biological pathways, each affect the risk for a distinct component of the AMD phenotype: CFH influences the drusen of dry AMD, whereas HTRA1 influences blood vessel development, the hallmark of the wet disease type. When the two processes are combined, it leads to the composite characteristics that are seen in some cases of AMD.

Hoh, her collaborators in Hong Kong, and her colleagues at Yale including Michael Snyder and Colin Barnstable in the Departments of Molecular, Cellular and Developmental Biology and Molecular Biophysics and Biochemistry, and Ophthalmology, did trans-racial gene mapping by comparing genomes between precisely defined populations to find the incidence of SNP in a Chinese population--96 with AMD and 130 with normal vision.

"We found that patients with the HTRA1 SNP were 10 times more likely to have wet AMD than those without this gene variant," said Hoh. "While this is only preliminary work, it points to possible directions for future treatment of wet AMD."

Hoh also worked on a replication study led by Kang Zhang at the University of Utah School of Medicine that found a link between the same SNP and AMD. Zhang and his team studied 581 Caucasian patients with AMD and 309 with normal vision. These patients had wet AMD as well as a large amount of drusen.

To confirm the association, the Utah team also examined several donor eyes and measured the expression of the gene and the encoded protein. They found that the expressions were elevated in the eyes of patients who carry HTRA1.

"The marker we have identified is very much associated with AMD, but no one has ever pinpointed the clinical features of the gene. We need to conduct further analysis in order to understand the biological mechanisms," said Hoh.

In addition to Hoh, Snyder and Barnstable, authors on the first study included first author Andrew DeWan, Mugen Liu, Stephen Hartman, Samuel Shao-Min Zhang, David T.L. Liu, Connie Zhao, Pancy O.S. Tam, Wai Man Chan, Dennis S.C. Lam and Chi Pui Pang.

In addition to Zhang and Hoh, authors on the second study included Zhenglin Yang, Nicola J. Camp, Hui Sun, Zongzhong Tong, Daniel Gibbs, D. Joshua Cameron, Haoyu Chen, Yu Zhao, Erik Pearson, Xi Li, Jeremy Chien, Andrew DeWan, Jennifer Harmon, Paul S. Bernstein, Viji Shridhar, Norman A. Zabriskie and Kimberly Howes.


Story Source:

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


Cite This Page:

Yale University. "Gene Linked To Aggressive 'Wet' Age-related Macular Degeneration." ScienceDaily. ScienceDaily, 27 November 2006. <www.sciencedaily.com/releases/2006/11/061122150330.htm>.
Yale University. (2006, November 27). Gene Linked To Aggressive 'Wet' Age-related Macular Degeneration. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2006/11/061122150330.htm
Yale University. "Gene Linked To Aggressive 'Wet' Age-related Macular Degeneration." ScienceDaily. www.sciencedaily.com/releases/2006/11/061122150330.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com
Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Despite Rising Death Toll, Many Survive Ebola

Despite Rising Death Toll, Many Survive Ebola

AP (Oct. 23, 2014) The family of a Dallas nurse infected with Ebola in the US says doctors can no longer detect the virus in her. Despite the mounting death toll in West Africa, there are survivors there too. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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