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 are 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, 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.
For Dr Sarah Ennis and Professor Andrew Lotery, University of Southampton, UK, please contact Sarah Watts, Media Relations, T) +44 (0) 23 8059 3807 E) S.A.Watts@soton.ac.uk / A.J.Lotery@soton.ac.uk / S.Ennis@soton.ac.uk
Dr Caroline Klaver, Erasmus Medical Centre, Netherlands T) +31-6-51934491 E) carolineklaver@yahoo.com
Full Article and Comment: http://press.thelancet.com/Macularfinal.pdf
Journal
The Lancet