Factor V (F5) Leiden (p.R506Q) Variant Analysis
CPT Code(s)
81241, G0452
Synonym(s)
Factor V, F5, Leiden, R506Q, hypercoagulability, coagulation factor V
Performed
Molecular Diagnostics Laboratory
Clinical Indication and Relevance
The assay is recommended in patients with venous thromboembolism (VTE) when the results will influence treatment and clinical management decisions. It is also useful in patients and certain asymptomatic relatives to reduce the risk of VTE through counseling about preventative measures in circumstances of elevated risk.
Methodology
DNA is isolated from the patient sample and the Factor V (FV) gene containing the Leiden variant site is PCR-amplified and analyzed using an allelic discrimination assay employing specific primers and TaqMan probes. Results are reported as normal, heterozygous variant or homozygous variant for the factor V Leiden (p.R506Q) variant.
Minimum Specimen Requirements
Collect
- Peripheral blood (PB): 3-5 mL, in purple top (EDTA) tube
- Yellow top (ACD) tube also acceptable
Transport
Room temperature or 2-8°C (wet ice or cold packs). Do not freeze.
Stability
Room temperature: 8 hours. Refrigerated: 48 hours.
Unacceptable Samples
Serum or plasma; frozen PB or BM; clotted blood; severely hemolyzed samples.
Turnaround time
Five to seven working days
View Requisition Sheet