FACTOR-V LEIDEN (FVQ-506) IS COMMON IN A BRAZILIAN POPULATION

Resistance to active protein C (APC) is the most common risk factor in venous thrombosis. A missense mutation in the factor V gene (factor V Leiden) is the molecular basis for this phenotype. Factor V Leiden wa s previously found in about 20% of unselected patients with thrombosis but also occurred in 3-5% of healthy Dutch controls. In the present s tudy of Brazilian patients with venous thrombosis we also observed a f requency of 20% for this factor. In addition, in healthy Brazilian con trols the frequency of the mutation was 2%. These data suggest that fa ctor V Leiden has a similar distribution worldwide irrespective of the ethnic origin of the population. (C) 1995 Wiley-Liss, Inc.