Prothrombin 20210 Mutation
A nucleotide change at position 20210 (Gly to Arg) of the prothrombin gene was found to be present in 1% of the normal control population versus 18% of patients with venus thromboembolism (VTE). This allele was found to increase the risk of thrombosis almost threefold because it is associated with elevated levels of prothrombin (usually greater than 1.15 U/ml, a 25% increase compared to the normal range). This was the first strong evidence of a quantitative trait locus mutation in the prothrombin gene influencing prothrombin activity levels and hence an individual’s risk for thrombosis.
Other associated thrombotic episodes linked to this mutation include coronary artery disease, especially in young women and people with stroke, venous thrombosis, mesenteric vein thrombosis, central retinal arterial thrombosis, or portal vein thrombosis.