Background and
purpose
Genetic thrombophilic
conditions such as those associated
with Factor V Leiden (FVL)
and the prothrombin mutant (PT
G20210A) have been identified as
risk factors for cerebral venous
thrombosis (CVT). Recently, a
single nucleotide polymorphism
(SNP) of the thrombin activatable
fibrinolysis inhibitor (TAFI G–438A) has been shown to be associated
with lower TAFI levels and
to decrease the risk for peripheral
venous thrombosis. Furthermore, a
protective role in juvenile stroke
was shown for a SNP of the vitamin
K dependent protein Z (PZ
Intron F G79A) which is linked
with low PZ levels.
Patients and
methods
In 77 consecutive patients
with CVT and in 203 randomly
selected population controls from
the same region of Southern
Germany, we investigated the
following functional SNPs using
PCR and restriction fragment
analysis techniques: TAFI G–438A,
PZ Intron F G79A, FVL and PT
G20210A.
Results
The prevalence
of FVL tended to be higher (OR
2.08, 95 % CI 0.91–4.75, p = 0.06)
and that of PT G20210A (OR 4.57,
95 % CI 1.45–14.44, p = 0.007) was
significantly higher in patients
with CVT than in controls. The
A–allele frequency of the TAFI G–438A polymorphism did not significantly
differ between patients
(21.3 %) and controls (26.9%; OR
0.71, 95 % CI 0.45–1.12; p = 0.17).
For the PZ G79A SNP, the frequency
of the A–allele was 19.5%
in CVT and 24.6% in controls (OR
0.77, 95 % CI 0.49–1.21; p = 0.31).
Conclusions
In this large series of
CVT patients, a positive association
with established thrombophilic
risk factors FVL and
especially the PT G20210A mutation
was confirmed. In contrast,
our study found no significant
association of CVT with SNPs of
the TAFI and the PZ genes. Other
than testing for FVL and the PT
G20210A mutation, exploration of
these potential thrombophilic variants
seems to be of limited value
in the investigation of CVT.
Key words genetics - cerebral
venous thrombosis - thrombophilia - polymorphism