Abstract
Purpose: :
To examine the association of the rs5888 Variant of SCARB1 (Genbank accession number NM_001082959.1, NM_005505.4; T>C 63587 [350 A>A] exon 8, 12q24.31) with Age-related Macular Degeneration (AMD).
Methods: :
Total DNA was isolated from 115 AMD subjects and 133 age-matched control subjects. All subjects underwent a complete dilated ophthalmic examination by Board certified ophthalmologists including fundus photos, fluorescence and/or indocyanine green angiography. The AMD subjects were further classified as nonexudative (29 subjects) or exudative (86 subjects). The SCARB1 gene was amplified by the Polymerase Chain reaction (PCR) and scored for the rs5888 polymorphism using restriction enzyme digestion with Afe I. Some PCR amplified products were sequenced at the UCLA Sequencing and Genotype Core to verify polymorphisms. Statistical analyses were performed using SISA software.
Results: :
Of the AMD patients studied in our population 52.1% were heterozygous for the rs5888 single nucleotide polymorphism (SNP) compared to 51.9% in the control population (Odds Ratio [OR] 0.74, 95% Confidence Intervals [CI] 0.45-1.2). The proportion of AMD homozygotes also did not differ significantly from the control population (OR of TT genotype 1.33, 95% CI 0.72-2.45; OR of CC genotype 1.14, 95%CI 0.66-1.96). Subgroup analysis was also performed to determine if the rs5888 variant was more prevalent in non-exudative, exudative, or control subjects and to determine if statistical significance emerged depending on inheritance pattern (dominant versus recessive). In all analyses, no statistically significant difference was observed.
Conclusions: :
Despite a previous report that rs5888 is found in a statistically significantly higher proportion of AMD patients compared to controls, we did not find a significant difference between AMD patients and controls in our population.
Keywords: age-related macular degeneration • genetics