To test the hypothesis that genetic polymorphisms of the apolipoproteinE (APOE) gene are associated with primary open-angleglaucoma (POAG), based on the association between neurodegenerative diseasesand the APOE genotype.
Genomic DNA was examined from an unrelated cohort of 137 POAG patientsand 75 control subjects from the ophthalmology department of the Royal VictoriaInfirmary. The APOE allele frequency (ϵ2, ϵ3,and ϵ4 alleles) was studied by polymerase chain reaction amplificationof the related locus (19q13.2), enzymatic digestion of the products, gel electrophoresis,and imaging under UV illumination. For statistical analysis, we used a logisticregression model that included intraocular pressure as a continuous variableto study the possible correlation between POAG and APOE allele frequency.
Logistic regression analysis showed no statistically significant associationbetween the frequency of the APOE allele and POAGfor the population studied, irrespective of the IOP (ϵ2 odds ratio, 0.82;95% confidence interval, 0.12-5.79 [P = .84]; ϵ3odds ratio, 0.39; 95% confidence interval, 0.10-1.49 [P = .17]; and ϵ4 odds ratio, 3.84; 95% confidence interval, 0.80-18.49[P = .09]).
In our cohort, the APOE genotype does not constitutea risk factor for developing POAG, even in patients with normal-tension glaucoma.
Apolipoprotein E polymorphisms do not appear to be contributory to POAG.