Predictive value of the vitamin K epoxide reductase complex subunit 1 G-1639A and C1173T single nucleotide polymorphisms in retinal vein occlusion

Background:  To determine if vitamin K epoxide reductase complex subunit 1 gene polymorphisms have an effect on the risk of having a retinal vein occlusion. Design:  Case-control study. Participants:  The study population consisted of 68 patients who were newly diagnosed with retinal vein occlusion and 66 sex-matched controls. Methods:  Genomic DNA was extracted from peripheral leukocytes from ethylenediamine tetra-acetic acid-anticoagulated blood. Genotyping of the vitamin K epoxide reductase complex subunit 1 G-1639A (rs 9923231) and C1173T (rs 9934438) single nucleotide polymorphisms was performed using real-time polymerase chain reaction and commercially available kits. Main Outcome Measures:  A full ophthalmological evaluation was performed in each subject, and all subjects were screened for hypertension, hypercholesterolaemia and diabetes. The genotypes of the vitamin K epoxide reductase complex subunit 1 single nucleotide polymorphisms were determined. Results:  The vitamin K epoxide reductase complex subunit 1 GG and CC genotypes were more frequent (41% vs. 21%; P = 0.021), and the combined GA/AA and CT/CC genotypes were less frequent in patients with retinal vein occlusion than in control subjects. After adjusting for hypertension, age, plasma fibrinogen levels and prevalence of diabetes and hypercholesterolaemia, the GG and CC genotypes were found to be an independent predictor of retinal vein occlusion (B = 2.28; odds ratio = 9.79; P = 0.003; 95% confidence interval: 2.22–43.24). Conclusion:  It was found that subjects with the vitamin K epoxide reductase complex subunit 1 GG and CC genotypes had a higher risk of retinal vein occlusion.