Abstract
Purpose::
Age-related macular degeneration (AMD) is the most common form of irreversible blindness in developed countries. Sequence variants in the complement factor H gene (CFH), which encodes a major regulator of the complement pathway, are associated with the risk for developing AMD. We evaluated whether variations in genes encoding other regulatory proteins of the same complement pathway are associated with AMD. We screened membrane cofactor protein (MCP) and decay-accelerating factor (DAF) - inhibitors of complement activation, and complement factor H related protein 5 (CFHR5) - a protein homologous to CFH and proposed to function in complement regulation.
Methods::
To date, a partial mutation screen of MCP (12 out of 13 coding exons), DAF (4 out of 10 coding exons), and CFHR5 (8 out of 10 coding exons) has been performed in 665 unrelated patients with AMD using direct genomic sequencing.
Results::
No sequence changes have been identified in MCP, DAF, or CFHR5.
Conclusions::
Although we have not completed these screens, we have found no sequence changes in three genes involved in regulating the complement cascade, MCP, DAF and CFHR5. Results to date indicate that defects in these genes are unlikely to be associated with AMD. However, we are completing our evaluation of the remaining exons in these patients.
Keywords: age-related macular degeneration • candidate gene analysis • mutations