Compound heterozygosity for the factor V HR2 haplotype and the factor V Leiden mutation is associated with an increased risk for venous thrombosis as compared with heterozygosity for factor V Leiden alone. Some studies suggest that the HR2 haplotype alone is an independent thrombotic risk factor. The HR2 haplotype alone is associated with a two-fold increase in risk of venous thromboembolism, although further study is underway on this topic. Double heterozygosity for factor V Leiden and the factor V HR2 haplotype has not been associated with a significantly higher risk of early or late pregnancy loss than a heterozygous factor V Leiden.
Indications for Testing:
- Personal history of 2 or more blood-clotting incidents
- Deep vein thrombosis
- Pulmonary embolism
- Superficial venous thrombosis, phlebitis or thrombophlebitis
- Family history of blood clots or factor V HR2
Sample Requirements: 5 - 7 mL whole blood in purple top (EDTA) tube
Sample Handling: Blood samples stored overnight should be refrigerated or kept cold. Blood samples should never be frozen. Specimens being sent from outside facilities should be packaged with a cold pack according to standard medical safety practices. The specimen should be shipped by overnight priority [scheduled to arrive by Friday AM at the latest].
Shipping Address: Center for Human Genetics Laboratory
10524 Euclid Ave, 6th Floor
Cleveland, OH 44106
216-983-1134
For local samples, please call the Center for Human Genetics Laboratory (216-983-1134) to arrange for sample pick-up.
Turn Around Time: 5-14 days
Cost/CPT codes: $103.08 / 83892, 83894, 83898, 83912