FACTOR-V AND ANTITHROMBIN GENE-MUTATIONS IN PATIENTS WITH IDIOPATHIC CENTRAL RETINAL VEIN OCCLUSION

A number of anticoagulants are found in plasma, helping to maintain th e balance between thrombosis and haemorrhage, Two of the most importan t are antithrombin and protein C, which inactivates factors V and Vm. Deficiencies are weal-recognised predisposing factors for systemic thr ombosis. To establish whether the factor V or Cambridge II antithrombi n mutations were present with an increased frequency in patients ,vith idiopathic central retinal vein occlusion (CRVO) we screened 50 such patients. DNA was isolated and the regions of the gene encoding for fa ctor V and antithrombin were amplified by means of the polymerase chai n reaction. Following digestion with restriction enzymes the products were electrophoresed in agarose gels, We identified a single patient w ith the factor V mutation and none with the antithrombin mutation Thes e findings suggest that resistance to activated protein C and antithro mbin mutations does not play a major role in CRVO.