BU geneticist Lindsay Farrer believes inflammation creates more trouble than most people think. A gene associated with inflammation also puts people at risk for age-related macular degeneration (AMD), says Farrer. AMD causes vision loss and even blindness. It currently afflicts nearly 10 million Americans.

Farrer and colleagues at the University of Texas Southwestern Medical Center and Sequenom, Inc., of San Diego, California, sifted through more than 14 million base pairs of DNA on an area of a single chromosome that has long been suspected of harboring a genetic defect causing AMD. Using a series of screening tests, they honed in on 24 suspect locations.

The researchers then analyzed the genomes of two groups — a test group with early stage AMD and a control group without the disease. They found one particular cluster of seven genes at one of the locations that differed significantly between the two groups. The area in question produces a protein called Complement Factor H (CFH) that helps to activate an inflammatory response. One variant of the gene appears to trigger excessive inflammation and to triple a person’s chances of eventually getting AMD, says Farrer. The statistical correlation between the genetic variation and AMD was at “a level of significance that we never see,” he adds.

Although the genetic finding may account for 50 percent of the cases of AMD, Farrer stresses that other environmental factors such as smoking and obesity also play a substantial role. He hopes that identifying patients with a genetic predisposition to the disease may eventually help predict which patients will better respond to different drug treatments.

For more information about Professor Farrer's work, see: http://www.bu.edu/alzresearch/team/faculty/farrer.html

— Elana Hayasaka

People with age-related macular degeneration (AMD) experience deteriorating sight in the center of their field of view, vision that is essential to everyday activities such as reading and driving. The loss of vision results from damage to the macula, the central part of the retina that is rich in photosensitive cells. This image shows the yellow deposits known as drusen, composed of inflammatory proteins that accumulate in the macula of those affected. BU geneticist Lindsay Farrer has identified a gene that is associated with both inflammation and risk of AMD.