• Test Code:
    1420
  • Department:
    Molecular Genetics
  • Test Synonyms:
    Factor V LeidenHereditary Resistance Activated Protein C ResistanceResistance to Activated Protein CActivated protein C resistanceAPC resistanceFactor V R506QFCV
  • CPT Code(s):
    81241
Background:

Factor V Leiden thrombophilia is an inherited disorder of blood clotting.  Factor V Leiden is the name of a specific gene mutation that results in thrombophilia, which is an increased tendency to form abnormal blood clots that can block blood vessels.  Afflicted persons present with a history of venous thromboembolism (VTE) manifesting as deep vein thrombosis (DVT) or of pulmonary embolism, especially in women with a history of VTE during pregnancy (or in association with oral contraceptive use) and in persons  with a personal or family history of recurrent thrombosis.
 
A coagulation screening test or DNA analysis of the F5 gene can be used to diagnose factor V Leiden thrombophilia.  Factor V Leiden refers to the specific G-to-A substitution at nucleotide 1691 in the gene for factor V that predicts a single amino-acid replacement (R506Q) at one of three APC cleavage sites in the factor V(a) molecule1.

Methodology:

Polymerase chain reaction/Fluorescence monitoring.

Specimen Requirements:

Blood:  6.0 mL in EDTA (purple-top) or ACD (yellow-top) tube

DNA: 10ng at a minimum of 100ng/µL (DNA must be extracted in a CLIA-certified laboratory or a laboratory meeting equivalent requirements as determined by the CAP and/or CMS)

A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES.  Please include detailed clinical information, including ethnicity, clinical history, and family history.

Test Performed (Days):

Weekly

Turn Around Time:

7 – 10 Days

Shipment Sensitivity Requirements:

  • Keep specimen cold during transit, but do not ship on dry ice. 
  • Please use the cold pack provided in the KDL shipping kit. 
  • Contact Client Services at (855) 535-1522 for shipping kits and instructions. 
  • Ship the specimen overnight express, using the FedEx priority overnight label provided. 

References:

  1. Kujovich, JL.  Factor V Leiden Thrombophilia. Gene Reviews.  http://www.ncbi.nlm.nih.gov/books/NBK1368/  Initial Posting: May 14, 1999; Last Update: March 9, 2010.

Additional Info:

PCR-based direct detection of codon 506 Factor V mutation causing resistance to activated protein C and familial thrombosis.  Call the lab at (855)535-1522 for more information.