Heterogeneous ethnic distribution of the factor V Leiden mutation

Inherited resistance to activated protein C caused by the factor V Leiden ( FVL) mutation is the most common genetic cause of venous thrombosis yet des cribed, being found in 20-60% of patients with venous thrombophilia. A rela tionship between the FVL mutation and an increased predisposition to arteri al thrombosis in young women was recently reported. We assessed the prevale nce of the FVL mutation in 440 individuals (880 chromosomes) belonging to f our different ethnic groups: Caucasians, African Blacks, Asians and Amerind ians. PCR amplification followed by Mnn digestion was employed to define th e genotype. The FVL mutation was found in a heterozygous state in four out of 152 Whites (2.6%), one out of 151 Amerindians (0.6%), and was absent amo ng 97 African Blacks and 40 Asians. Our results confirm that FVL has a hete rogeneous distribution in different human populations, a fact that may cont ribute to geographic and ethnic differences in the prevalence of thrombotic diseases. In addition, these data may be helpful in decisions regarding th e usefulness of screening for the FVL mutation in subjects at risk for thro mbosis.