Thromboembolic phenomenona have been described in patients with thalassemia
major. In a multicenter, retrospective study we investigated the effect of
factor V (FV Leiden), prothrombin (FII), methylene-tetrahydrofol ate reduc
tase (MTHFR), PIA2 glycoprotein IIIa (GpIIIa) and factor VII gene polymorph
isms on the risk of thrombosis in thalassemic patients. A higher prevalence
of the FVII H7 allele in subjects without thrombosis suggests that this ge
netic marker confers protection against thrombosis.