Navigation Links
Gene Linked With Aggressive 'Wet' Form Of AMD

Two recent articles in Science by researchers at Yale School of Medicine has reported about 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.

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 Molecu lar 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.

Source-Eurekalert
SI
'"/>




Related medicine news :

1. Low Cholesterol Linked to Severe Depression and Violent Behavior in Men
2. Cough Syrup Ingredient Linked to Stroke
3. Irregular Periods Linked to Diabetes
4. Hormones Linked To Migraines
5. Triglycerides Linked To Stroke Risk
6. Smoking Linked To Low Infant Birth Weight
7. Nausea Linked To Anxiety And Depression
8. Painkiller Linked to Deaths
9. High Levels of Protein Linked to Brain Shrinkage
10. Snoring Linked To Headaches
11. Hormone Therapy Linked to Dementia
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/29/2017)... ... March 29, 2017 , ... The Professional Squash ... has enlisted New York City-based sports and entertainment marketing firm Leverage Agency as ... opportunities for the Professional Squash Association (PSA), which includes first-time ever title sponsorship, ...
(Date:3/29/2017)... ... March 30, 2017 , ... Youth Futures International (YFI) premiered its ... from high school and college students who have participated in the program every summer. ... YFI is now accepting applications for enrollment. Visit http://www.ghana.yfiexperience.org to learn ...
(Date:3/29/2017)... ... March 29, 2017 , ... AngioGenesis Labs sold ... in Mississippi. AngioGenesis Labs, makers of HeartBoost, BrainBest and BeautyBest, achieved these results ... in HeartBoost, an over the counter heart healthy drink, can reduce Arterial Plaque, ...
(Date:3/29/2017)... ... March 29, 2017 , ... Dr. Angela Cotey, a noted general ... accepting new pediatric patients, with or without a referral. Dr. Cotey knows that ... orthodontic outcome and experience. When patients receive early treatment, they may achieve straight teeth ...
(Date:3/29/2017)... ... ... Curio Wellness , a premium medical cannabis brand and trusted healthcare ... team with prominent executives from both inside and outside the cannabis industry. , ... Dumbauld , who has more than twenty years of business leadership and investment experience ...
Breaking Medicine News(10 mins):
(Date:3/29/2017)... March 29, 2017  Spiral Therapeutics, Inc. today ... Bionure Farma, S.L. for the worldwide exclusive rights ... in the field of otolaryngology for aggregate payments ... The agreement provides Spiral with the option ... differentiated product profile. Under the terms of the ...
(Date:3/29/2017)... , March 29, 2017   Royal ... leader in health technology, and PathAI, a company ... collaborating with the aim to develop solutions that ... of cancer and other diseases. The partnership aims ... enabling this form of artificial intelligence to be ...
(Date:3/29/2017)... , USA, March 29, 2017 Stryker ... that Cares by People magazine, in partnership with Great ... 50 companies on the list. This list highlights the ... have succeeded in business while also demonstrating respect, compassion ... environment.  To determine the companies on ...
Breaking Medicine Technology: