ABSTRACT
OBJECTIVE: Branch retinal vein occlusion (BRVO) is a common cause of severe visual loss. Numerous risk factors, including arterial hypertension, diabetes mellitus, and arteriosclerosis, have been identified. Gene polymorphisms affecting hemostasis may also play a role in the pathogenesis of BRVO. The present study was therefore done to determine the prevalence of genetic polymorphisms in factors implicated in hypercoagulability among patients with BRVO. DESIGN: Retrospective case-control study. PARTICIPANTS: The study cohort consisted of 294 patients with BRVO and 294 control subjects, matched for age and gender. METHODS: Determination of genotypes was done by allele-specific digestion of polymerase chain reaction products, or by 5' exonuclease assay (TaqMan). MAIN OUTCOME PARAMETERS: Genotypes of factor V R506Q (factor V Leiden), prothrombin 20210G>A, fibrinogen beta -455G> A, factor XII (FXII) 46C>T, and ITGA2 807C>T (platelet glycoprotein Ia [GPIa] 807C>T) and ITGB3 L59P (platelet GPIIIa PlA1/PlA2) polymorphisms. RESULTS: Genotype distributions of the investigated gene polymorphisms did not differ significantly between patients and control subjects. In contrast, significantly increased prevalences of arterial hypertension and hypercholesterolemia were found among patients with BRVO. In a logistic regression analysis, the presence of arterial hypertension was associated with an odds ratio (OR) of 2.32 (95% confidence interval [CI], 1.62-3.32), whereas hypercholesterolemia yielded an OR of 2.54 (95% CI, 1.74-3.70) for BRVO. CONCLUSION: Our data indicate that the prevalences of the investigated gene polymorphisms do not differ significantly in patients with BRVO and control subjects. This suggests that these polymorphisms are not major risk factors for BRVO.
Subject(s)
Polymorphism, Genetic/physiology , Retinal Vein Occlusion/genetics , Thrombophilia/genetics , Adult , Aged , Aged, 80 and over , Case-Control Studies , Factor V/genetics , Factor XII/genetics , Female , Fibrinogen/genetics , Genotype , Humans , Hypercholesterolemia/genetics , Hypertension/genetics , Integrin alpha2/genetics , Integrin beta3/genetics , Male , Middle Aged , Polymerase Chain Reaction , Prevalence , Prothrombin/genetics , Retrospective Studies , Risk FactorsABSTRACT
The insertion/deletion (I/D) polymorphism of the gene for angiotensin-converting-enzyme (ACE) is associated with ACE plasma levels and activity. Conflicting results have been reported about the relevance of this polymorphism for venous thrombosis. The aim of the present study was to analyze the role of this polymorphism for deep venous thrombosis. The study was designed as a case-control study, including 330 patients with documented deep venous thrombosis and 354 controls. ACE genotype was determined by size-analysis of polymerase chain reaction products. Results showed that, ACE genotype frequencies were similar between patients (II: 24.8%; ID: 43.3%; DD: 31.8%) and controls (II: 22.9%; ID: 50.6%; DD: 26.6%, P = 0.15). The adjusted odds ratio of carriers of the DD geno-type for venous thrombosis was 1.24 (95% confidence interval 0.90-1.80). The polymorphism was furthermore not associated with age at first thromboembolic event or the occurrence of pulmonary embolism. From these results, we can conclude that the ACE I/D polymorphism is not a significant risk factor for deep venous thrombosis.
