Genetic correlation between Prothrombin G20210A polymorphism and retinal vein occlusion risk

The aim of this study was to perform an updated meta-analysis to quantitatively investigate the association between G20210A polymorphism of Prothrombin gene and the risk of retinal vein occlusion (RVO), based on the available publications with inconsistent results. We utilized the Stata software to perform the heterogeneity test, association test, Begg's and Egger's tests, and sensitivity analysis. We searched three on-line databases (PubMed, Embase, and WOS) and obtained a total of 422 articles. Based on our selection criteria, 24 case-control studies were finally enrolled in this overall meta-analysis; a subgroup analysis by the factors ethnicity, control source, and RVO type was done. Through the association test of overall meta-analysis, we did not observe a significant difference between RVO cases and controls under the A vs G (allele) (z=1.49, P=0.137), A vs G (carrier) (z=1.42, P =0.155), GA vs GG (z=1.50, P=0.135), and GA+AA vs GG (z=1.50, P=0.135). Furthermore, we observed similar negative results in the association test of subgroup analysis (all P>0.05). Heterogeneity, Begg's, and Egger's tests excluded the presence of high heterogeneity and publication bias. Statistically stable results were observed in the sensitivity analyses. Based on integrated analysis of the current evidence, Prothrombin gene G20210A polymorphism is likely unrelated to the risk of RVO.

Thrombophilic mutations and risk of retinal vein occlusion

PURPOSE: The association of retinal vein occlusion and hereditary thrombophilia abnormalities is not established, with controversial results in the literature. This study investigates the association between retinal vein occlusion and three thrombophilic mutations: factor V 1691A (factor V Leiden), prothrombin 20210A (PT 20210A) and homozygous methylenetetrahydrofolate reductase 677T (MTHFR 677TT). METHODS: 55 consecutive retinal vein occlusion patients and 55 controls matched by age, gender and race, were tested for the presence of the following mutations: factor V Leiden, PT 20210A and MTHFR 677TT. The frequencies of the three mutations in cases and controls were compared. RESULTS: Factor V Leiden was found in 3.6 percent of patients and in 0 percent of controls; PT 20210A was found in 1.8 percent of patients and 3.6 percent of controls, (matched-pair odds ratio, 0.5; 95 percent confidence interval, 0.04 to 5.51); MTHFR 677TT was found in 9 percent of patients and 9 percent of controls (matched-pair odds ratio, 1; 95 percent confidence interval, 0.92 to 3.45). Arterial hypertension was more frequent in patients than controls (matched-pair odds ratio, 3.4; 95 percent confidence interval, 1.25 to 9.21). CONCLUSIONS: This study suggests that thrombophilic mutations are not risk factors for RVO. Routine investigation of hereditary thrombophilia in these patients is not justified.

OBJETIVOS: A associação entre oclusão venosa retiniana e trombofilias hereditárias não está estabelecida, com resultados controversos na literatura. O presente estudo investiga a associação entre a oclusão venosa retiniana e três mutações trombofílicas: fator V 1691A (fator V Leiden), protrombina 20210A (PT 20210A) e mutação C677T do gene da metileno-tetra-hidro-folato redutase (MTHFR 677TT). MÉTODOS: Cinquenta e cinco pacientes portadores de oclusão venosa retiniana e 55 controles pareados por idade, sexo e raça foram testados para a presença das seguintes mutações: fator V Leiden, PT 20210A e MTHFR 677TT. As freqüências das três mutações em casos e controles foram comparadas. RESULTADOS: Fator V Leiden foi encontrado em 3,6 por cento dos pacientes e em 0 por cento dos controles; PT 20210A foi encontrada em 1.8 por cento dos pacientes e em 3,6 por cento dos controles, (odds ratio, 0,5; 95 por cento IC, 0,04 to 5,51); MTHFR 677TT foi encontrada em 9 por cento dos pacientes e em 9 por cento dos controles (odds ratio, 1; 95 por cento IC, 0,92 to 3,45). Hipertensão arterial foi encontrada mais freqüentemente em pacientes do que em controles (odds ratio, 3,4; 95 por cento IC, 1,25 to 9,21). CONCLUSÕES: O presente estudo sugere que mutações trombofílicas não são fatores de risco para oclusão venosa retiniana. A investigação rotineira para trombofilias hereditárias neste grupo de pacientes não é indicada.