Disease Characteristic
Mutation in prothrombin (factor II) gene is a major risk factor for venous thrombosis and certain arterial thrombotic conditions, it is associated with increased prothrombin levels.

How Common is Factor-II Mutation?
It is present in 1-3% of the general population and after the factor V Leiden mutation it is the most common genetic risk factor for venous thrombosis.
   
Prevalence
The prevalence of factor II G20210A heterozygotes is 1-6% in Caucasians, whereas it is rare in non-Caucasian populations.
   
Genes and Mutations (Genotype-Phenotype Relationships)
A single copy of prothrombin (factor II) mutation G-20210-A increases the risk of venous thrombosis 3-11%. Homozygosity further increases this risk.

Phenotypes                       
Deep Vein thrombosis
Pulmonary embolism
Premature myocardial infarction in women
Premature ischemic stroke in the absence of hypertension
Cerebral vein thrombosis

Criteria for Genetic Testing

Deep vein thrombosis
Pulmonary embolism

Cerebral vein thrombosis
Premature ischemic stroke
Women with premature myocardial infarction
Family history of thrombosis