Association of the Apolipoprotein E Gene with Primary Open–Angle Glaucoma

Abstract

Abstract: : Purpose: To investigate the genotype of coding exon 4 of apolipoprotein E gene (APOE) and its promoter region for single nucleotide polymorphisms (SNP), at positions –491, –427 and –219 in patients with primary open–angle glaucoma (POAG). Methods: Genomic DNA extracted from peripheral blood samples from 200 unrelated patients with POAG and 201 unrelated control subjects were analysed by normal polymerase chain reaction (PCR), nested PCR, restriction enzyme digestion, and polyacrylamide gel electrophoresis. Results: Significant difference by Χ²–test was observed in the allele frequency of SNP –491A>T in the promoter region (P = 0.016) between patients and controls. There was a higher frequency of both homozygous and heterozygous SNP –491A>T in patients than in controls. For SNP –219T>G, significant difference (P = 0.0004) was shown in the genotype frequency. The frequency of homozygous SNP –219T>G in patients was higher than that in controls. Four genotypes (ε2/ε4, ε2/ε3, ε3/ε4 and ε3/ε3) were found in the exon 4 and both allele and genotype frequencies showed significant differences (P = 0.037 and P = 0.033 respectively) between patients and controls. Conclusions:These results show evidence on the association of APOE with POAG and suggest that –491A>T and –219T>G could be risk factors. Our data also indicates that the genotype ε4 in exon 4 could confer protective effects against POAG.CR: None Support: A direct grant from the Medicine Panel of The Chinese University of Hong Kong

Keywords: genetics • gene screening • visual impairment: neuro–ophthalmological disease