Gene discovery may help hunt for blindness cure
Tue Oct 7, 12:50 PM ET
Scientists have discovered a gene mutation linked to the most common cause of blindness in the developed world, holding out the prospect of better treatments and perhaps eventually a cure.
British scientists said on Tuesday they had found six variants within the gene called Serping1 that were associated with age-related macular degeneration (AMD).
"Our findings add to the growing understanding of the genetics of age-related macular degeneration, which should ultimately lead to novel treatments for this common and devastating disease," Sarah Ennis and Andrew Lotery of the University of Southampton reported in the Lancet journal.
AMD -- which involves damage to the delicate cells of the macula, a region at the center of the retina -- is increasingly common as people get older.
Around 90 percent of patients diagnosed with AMD have the so-called dry version, for which no treatment is currently available.
The rest have wet AMD, which occurs when tiny new blood vessels grow between the retina and the back of the eye. This form of the disease can be treated with modern drugs.
(Reporting by Ben Hirschler; Editing by Dominic Evans
Genetic Link To Age-Related Macular Degeneration Reported In The Lancet
A new genetic association with the condition age-related macular degeneration (AMD) is reported in an Article published early Online and in an upcoming edition of The Lancet, written by Dr Sarah Ennis and Professor Andrew Lotery, University of Southampton, UK, and colleagues.
AMD is the most prevalent form of visual impairment and blindness in developed countries. The recent Rotterdam study showed 64% of people aged 80 years or over have signs of the disease, and around 12% of this age group have AMD so severe it causes them to go blind. In the UK, the yearly economic burden of AMD is estimated to be some £80 million. And the total yearly costs of health-care usage are seven times higher for patients with AMD than for controls, largely attributable to the decreased independence of affected individuals and increased need for assistance with daily living.
The researchers looked at a UK sample of patients with AMD (479) and controls (479) and screened 32 genes potentially involved in the condition. They found an association with the SERPING1 gene, which is involved in production of proteins for the 'complement' system within the eye that helps clear foreign material and infection. By analysing single base pair mutations, the group initially identified a single variant within the SERPING1 gene in which frequencies of the variant forms were significantly distorted in patients with AMD compared to controls. The researchers then replicated their findings in a separate US cohort of patients, and further verified their finding by conducting a secondary high-density analysis that revealed an additional five variants in the SERPING1 gene, all of which were associated with AMD.
The authors conclude: "Our study shows a strong association between age-related macular degeneration and SERPING1, with supporting evidence from an independent replication and a secondary high-density scan of the gene...genetic variation in SERPING1 may implicate the classic pathway of complement activation in AMD...Our findings add to the growing understanding of the genetics of age-related macular degeneration, which should ultimately lead to novel treatments for this common and devastating disease."
In an accompanying Comment (login required) Dr Caroline Klaver, Erasmus Medical Centre, Netherlands, and Professor Arthur Bergen, Netherlands Institute for Neurosciences, Netherlands, say that the next steps in the research should include replication of the study's findings in large independent cohorts as well as functional studies.
Article
"Association between the SERPING1 gene and age-related macular degeneration: a two-stage case-control study"
Sarah Ennis, Catherine Jomary, Robert Mullins, Angela Cree, Xiaoli Chen, Alex MacLeod, Stephen Jones, Andrew Collins, Edwin Stone, Andrew Lotery
The Lancet - DOI:10.1016/S0140-6736(08)61348-3
Click here to read the Summary of the Article online.
The Lancet
Article URL:
http://www.medicalnewstoday.com/articles/124479.php
Main News Category: Eye Health / Blindness
Also Appears In: Genetics,