A tag-single nucleotide polymorphisms approach to the vascular endothelial growth factor-A gene in age-related macular degeneration

Abstract

Purpose: Age-related macular degeneration (AMD) is the leading cause of poor vision in the developed world, and its pathogenesis remains unknown. The most devastating form of end stage disease is neovascular or wet AMD, where there is abnormal growth of new blood vessels under the retina. Vascular endothelial growth factor (VEGF) is thought to be a major player in the stimulus of this abnormal growth of blood vessels. We undertook a case-control association study to investigate the VEGF-A gene, a known angiogenic gene that has previously been associated with AMD.

Methods: We recruited 577 individuals with AMD (early, atrophic, and neovascular AMD) and 173 ethnically matched controls for our study. We employed a tag-single nucleotide polymorphisms (tSNP) approach to investigate this gene using a series of seven tSNPs that encompassed the coding region of the VEGF gene as well as its promoter. Alleles were determined by a MALDI-TOF based approach followed by statistical analysis.

Results: One SNP (rs3024997) showed evidence of departure from Hardy-Weinberg equilibrium in only the AMD cases. Therefore, it was retained for further analysis. All other SNPs in our study showed no departure from Hardy-Weinberg equilibrium. No association was found between any of the VEGF tSNPs analyzed in our study and AMD nor any of its sub-types.

Conclusions: Using a tSNP approach, we found no evidence of an association of these SNPs within the VEGF-A gene being associated with either AMD or any of its subtypes in our population.