Researchers at Tufts Medical Center and collaborators discovered a new biological pathway for advanced age-related macular degeneration (AMD) that implicates a role of the hepatic lipase gene, LIPC. This discovery will improve understanding of the disease by providing researchers another developmental pathway to explore for prevention and treatment. The paper, titled "Genome-Wide Association Study of Advanced Age-Related Macular Degeneration Identifies a Role of the Hepatic Lipase gene (LIPC)", has been published in the Proceedings of the National Academy of Sciences, April 12, 2010.
In the multidisciplinary study led by Johanna M. Seddon, MD, ScM, Professor of Ophthalmology at Tufts University School of Medicine and Director of the Ophthalmic Epidemiology and Genetics Service at Tufts Medical Center, researchers genotyped samples from 979 advanced AMD cases and 1,709 controls using the Affymetrix 6.0 platform with replication in 5,789 cases and 4,234 controls in seven independent cohorts. The most significant gene association was a functional variant in the hepatic lipase (LIPC) gene.
Seddon and colleagues' data showed that the LIPC gene variation decreased risk of AMD. This gene is involved in raising serum levels of high-density lipoprotein cholesterol (HDL). The association with LIPC and other new HDL genes implicated in their study may not be directly related to raising or lowering levels of HDL and other mechanisms could be involved. "Identifying disease pathways is an important step toward the goal of developing new therapies and preventing visual loss due to AMD," said Dr. Seddon, a physician and macular degeneration specialist.
Coauthors were from collaborating institutions worldwide including Massachusetts General Hospital, Johns Hopkins University School of Medicine, University of Utah School of Medicine, Columbia University in New York, Washington University School of Medicine in St. Louis, MO, and University Paris in Creteil, France.
Advanced macular degeneration is the leading cause of blindness in the developed world among people over the age of 50. More than 15 million people in North America are currently affected by the disease.