Laboratory Test Information Guide

Details for Thrombophilia (associated with Factor V deficiency)

Test Name: Thrombophilia (associated with Factor V deficiency)
Alternate Name(s): Factor V
Familial Thrombophilia
Prothrombin/Factor V Prothrombin
Laboratory: Molecular Diagnostics
Specimen Type: 1 x 4 mL K2 or K3 EDTA Lavender top Vacutainer tube-may be a frozen aliquot.
Collection Information: Blood samples may be maintained at room temperature or a frozen aliquot is also acceptable.
Requisition: MOLECULAR DIAGNOSTIC REQUISITION
Test Schedule: As Required
Monday - Friday
0800 - 1600 h
Turnaround time from when specimen
is received in testing laboratory:
 
Routine
4 weeks
Stat
 
 
Reference Range: See report
Effective Date:  
Revised Date: 2016-03-21
Critical Value: N/A
Interpretive Comments: Resistance to activated protein C (APC) is a major cause of familial thrombophilia, and can be corrected by an anticoagulant activity expressed by purified factor V. It has been suggested that a point mutation in the gene coding for factor V is responsible for APC resistance1,2. This point mutation, (*1601G>A), occurring toward the 3' end of exon 10 of the factor V gene, is predicted to cause a mis-sense mutation in the APC cleavage site, (Arg506Gln) and confers an increase in the relative risk of a first episode of venous thrombosis of x7 for heterzygote carriers, x35 for heterzygote carriers taking oral contraceptive medication, and x 80 for individuals homozygous for the Factor V Leiden mutation3. Analysis of FV Leiden mutation at the 1601G locus utilizes a kit-based method from Roche Diagnostics which is adapted from published methodology4 and utilizes real-time PCR analysis on a Roche LightCyclerTM to analyze the hybridization of fluophorelabelled, amplicon-specific oligonucleotides to a leukocyte-derived genomic DNA template.

* FV cDNA coding sequence from GenBank Acession#M16967. Numbered according to HGVS nomenclature as in den Dunnen et al Hum Genet (2001) 109:121-124, initial coding ATG=1.

References

1. Zoller et al. (1994) Lancet 343:1536-1538
2. Greengard et al. (1994) NEJM 331:1559-1561
3. Bauer (2001) Ann Intern Med 135:367-373
4. van den Bergh F et al (2000) Clin Chem 46:1191-1195
Special Processing:  
Comments: For more information click on:
Molecular Diagnostic Laboratory
Method of Analysis: QT-RT PCR Light Cycler
Critical Information Required:  
Storage & Shipment: Must be received in testing laboratory within 5 days of collection, shipped at room temperature by courier/overnight delivery.
System Codes: 
Cerner
FVL
 
Referred To:  

Questions? Comments? Contact Laura Gopaul