Abstract
Purpose :
Several rare genetic variants in the complement factor H (CFH) and its association with age-related macular degeneration (AMD) have been described recently. However there is limited literature on the phenotypes accompanying these variants. To help ophthalmologists in their decision of doing additional genetic testing, we aim to describe the phenotypical characteristics of patients with AMD carrying a rare variant in the CFH gene.
Methods :
We searched the clinical database of the Department of Ophthalmology at the Radboud university medical center and the European Genetic Database (EUGENDA) for subjects with a variant in CFH. Whole exome sequencing and/or Sanger sequencing was performed to detect variants in the CFH gene. We selected cases carrying variants with protein changing coding regions and a population frequency (MAF) of less than 1%. In total 54 subjects, with 43 different CFH variants, were included in this study. Fundus features were graded based on color fundus photographs of both eyes, and if available also on other image modalities. The following features were assessed: presence of drusen, type and number of drusen, location of drusen, presence of pigmentary abnormalities, geographic atrophy or signs of neovascularization.
Results :
The mean age of first symptoms in these patients was 58 years (SD 13.0). There was a high degree of symmetry between the eyes of patients carrying a rare variant in CFH. The drusen area inside the ETDRS grid was very extensive, but in most cases also peripheral (small hard) drusen were present, known as cuticular drusen.
Conclusions :
AMD patients carrying a rare genetic variant in the CFH gene have a relatively early age of first symptoms, a high grade of symmetry between the two eyes, an extensive drusen area and in most cases also peripheral drusen. These characteristics could help ophthalmologists to select patients for additional genetic testing more efficiently.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.