Our Tests

Prothrombin Gene

Also known as: Prothrombin Gene Mutation

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A specific mutation in the prothrombin gene (F2) places a person at increased risk of venous thrombosis. This predisposition in inherited as an autosomal dominant disorder.

Clinical Utility

The presence of one mutated F2 gene increases the risk of venous thrombosis by 2-5-fold. There is dispute regarding the clinical utility of this information in an unaffected patient, or in the management of an affected patient. The presence of two mutated F2 genes is associated with much higher risk of venous thrombosis; the recurrence risk is presumably increased as well.

This is an assay for heritable mutations. It may raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient. The interpretation of the result may also be dependent on the family history and the interpretation of other studies.



Test Method

Analysis of F2 gene for the 20210G>A (c.*97G>A) variant.

Test Ordering

This test can be requested by any medical practitioner.

4 mL blood in EDTA (separate tube required). Specimens may be collected by the requesting practitioner or at any Sonic Healthcare pathology collection centre.

To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.

We also recommend that the patient or another adult check the labelling of request forms and sample tubes.

Special Instructions

Consider other genetic risk factors for thrombosis (Factor V Leiden).



This test may have a rebate for all or part of the cost.

Medicare Rebate

This test has a Medicare rebate of $31.00, subject to the requirements of the Medicare descriptor being met. The MBS item number is 73308.

Turnaround Time

5 working days.