7 new genes linked to common cause of blindness identified

Researchers have identified seven new genetic regions associated with age-related macular degeneration (AMD) - a common cause of blindness in older individuals.
The findings by an international team of investigators, published in the journal Nature Genetics, could point to new biological pathways and therapeutic targets for AMD.
The AMD Gene Consortium, a network of 18 research groups also confirmed 12 genetic loci identified in previous studies.
The study represents the most comprehensive genome-wide analysis of genetic variations associated with AMD.
The consortium's efforts have now explained up to 65 per cent of the genetics of AMD, said Jonathan Haines, director of the Vanderbilt Center for Human Genetics Research.

In addition to genetic causes, which may account for about half of all cases of AMD, risk factors include age, smoking, high blood pressure, obesity and diet.

"We're getting closer and closer to understanding the full list of risk factors for AMD," said Haines, one of the lead authors of the study.
AMD is a progressive neurodegenerative disease that kills photo-receptor cells in the macula - the region of the retina responsible for sharp, detailed central vision.
As AMD advances, it robs individuals of the central vision necessary for everyday activities like reading, driving, watching television and identifying faces.
About 2 million people in the US have advanced AMD, according to the National Eye Institute.

"It was very clear that if we wanted to make real progress in understanding the genetics of AMD, we needed to pull all of these various datasets together - which is what the AMD Gene Consortium has done," Haines said in a statement.
The researchers examined genetic data from more than 17,000 patients with advanced AMD and more than 60,000 people without AMD.
The loci they identified include genes involved in immune system signalling, lipid metabolism, remodelling of the matrix that surrounds cells and blood vessel development. The researchers are continuing to study the genetic regions, Haines said.