Factor V (His 1299 Arg) in young Turkish patients with cerebral infarct

Inherited gene defects related to the coagulation system have been reported as risk factors for stroke. Recently, a genetic component in the factor V (FV) gene that contributes to activated protein C resistance both in the pr esence and absence of FV 1691 G-->A was reported. This highly conserved FV gene haplotype was marked as R2 polymorphism, an A to G alteration at posit ion 4070 in exon 13 that predicts the His 1299 Arg substitutions. The aim o f this study was to evaluate the role of this mutation in Turkish children with ischemic infarct. The case-control study included 48 patients with cer ebral infarction; all were 18 years of age or younger (range: 10 months to 18 years). Ten (20.8%) of the 48 patients were found to carry the FV 1299 H is-->Arg mutation, one being homozygous. One patient who had a combination of FV 1691 G-->A and protein C deficiency also carried the FV 4070A mutatio n. A homozygous FV 1299A patient had a prothrombin (PT) 20210A mutation in the heterozygous state. The cerebral infarct risk for FV 1299 was found to be 2.4 (95% confidence interval 0.9-6.8) for all groups. When underlying co nditions were excluded, the incidence of FV 1299 was found to be 8/35 (22.8 %), but the risk was almost the same. When two other common thrombophilic m utations (i.e. FV 1691 G-->A and PT 20210 G-->A) were excluded, the inciden ce of FV 4070 mutation increased to 7/21 (33.3%). The risk also increased t o 3.9 (95% confidence interval 1.2-12.3). Copyright (C) 2000 S. Karger AG, Basel.