Is the factor XIII 34Val/Leu polymorphism a protective factor for cerebrovascular disease?

A frequent polymorphism in the factor XIII (FXIII) A-subunit gene, leading to a Val to Leu amino acid exchange at position 34, suggested to affect clot stability, has been associated with a decreased risk for venous thromboembolism and myocardial infarction. Its role in the development of stroke is still under investigation. Ninety-four patients with primary arterial intracerebral haemorrhage (mean age +/- standard deviation: 69 +/- 14 years; 48 men, 46 women), 718 patients with ischaemic stroke (63 +/- 14 years; 395 men, 323 women) and 369 healthy control subjects (59 +/- 14 years; 299 men, 170 women) were analysed for FXIII Val34Leu. No differences in genotype distribution between all three groups were observed. Also, no significant differences in the genotype distribution were found between subgroups of patients stratified according to age, sex, aetiology, history of hypertension, antiplatelet or anticoagulant medication and other vascular risk factors. In contrast to previously reported findings in smaller collectives, our data suggest that an association of the FXIII Val34Leu polymorphism with a decreased risk of ischaemic stroke or an increased risk of intracerebral haemorrhage is highly unlikely. Thus, screening for the FXIII Val34Leu polymorphism will not contribute significantly to the risk prediction of cerebrovascular disease.