Abstract
Purpose: :
Two major AMD susceptibility loci have recently been identified as contributing significantly to the manifestation of AMD. We seek to assess the genetic influence of these loci in AMD and cataract cohorts derived from Northern Ireland.
Methods: :
593 samples were investigated. Sporadic AMD cases (N=285), age–related cataract (N=166) and control cohort (N=142) were collected from the Retinal Clinic at the Department of Ophthalmology, Royal Group of Hospitals, Belfast. All AMD patients were graded in accordance with the criteria established by the Rotterdam study. Ascertainment of genotypic status was undertaken in all cohorts at the following SNP sites: CFH rs800292, rs3766404, rs1061170, rs203674 and at LOC387715 rs10490924 using ABI validated SNP assays and an ABI 7900HT genetic analyser. Genetic influence and allelic interaction at both loci were assessed between cohorts using logistical regression.
Results: :
Preliminary statistical analysis suggests that the genetic influence of these loci on AMD manifestation are similar to those previously reported in other investigations. LOC387715 would also appear to be associated with age–related cataract formation and additional samples are currently being assessed.
Conclusions: :
This study confirms that in Northern Ireland, as has been reported in other populations, CFH and LOC387715 are major susceptibility loci associated with the manifestation of AMD. Logistical regression suggests that both contribute independently but additively to AMD progression. The reduced influence of CFH reported in relation to AMD is most likely because the control cohort used in this investigation is derived from the general population and not selected specifically to be free from any AMD disease symptoms. While CFH protein function and its role within the immune response is widely known, the specific contribution of the significant genotypic variation observed in terms of disease progression has yet to be elucidated. Nothing is known about the protein function of LOC387715, its role in AMD disease manifestation or its interaction, if any, with additional unidentified proteins or environmental risk factors that lead to the progression of age–related ophthalmic disease such as AMD or cataract.
Keywords: age-related macular degeneration • cataract • genetics