Test Details
Methodology
Allele-specific polymerase chain reaction (PCR)
Result Turnaround Time
5 - 7 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
Contributes to the risk assessment for venous thromboembolism (VTE) to better inform decisions regarding treatment and clinical management decisions of patients with relevant personal history of VTE and potential preventative care for patients with significant family history of VTE.
Limitations
Variant analyzed: c.1601G>A (p.Arg534Gln), referred to as Factor V Leiden; NM_000130.5. Results must be combined with clinical information for the most accurate interpretation. Molecular-based testing is highly accurate, but as in any laboratory test, diagnostic errors may occur. False positive or false negative results may occur for reasons that include genetic variants, blood transfusions, bone marrow transplantation, somatic or tissue-specific mosaicism, mislabeled samples, or erroneous representation of family relationships.
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Footnotes
References
Custom Additional Information
Venous thromboembolism is a multifactorial disease influenced by genetic, environmental, and circumstantial risk factors. The c.1601G>A (p. Arg534Gln) variant in the F5 gene, commonly referred to as Factor V Leiden, is a genetic risk factor for venous thromboembolism. Heterozygous carriers of this variant have a 6- to 8-fold increased risk for venous thromboembolism. Individuals homozygous for this variant (ie, they have a copy of the variant on each chromosome) have an approximately 80-fold increased risk for venous thromboembolism. Individuals who carry both a *97G>A variant in the F2 gene and Factor V Leiden have an approximately 20-fold increased risk for venous thromboembolism. Risks are likely to be even higher in more complex genotype combinations involving the F2 c.*97G>A variant and Factor V Leiden.1 Additional risk factors include but are not limited to: deficiency of protein C, protein S, or antithrombin III, age, male sex, personal or family history of deep vein thromboembolism, smoking, surgery, prolonged immobilization, malignant neoplasm, tamoxifen treatment, raloxifene treatment, oral contraceptive use, hormone replacement therapy, and pregnancy. Management of thrombotic risk and thrombotic events should follow established guidelines and fit the clinical circumstance. This result cannot predict the occurrence or recurrence of a thrombotic event.
Genetic coordinators are available for health care providers to discuss results and for information on how to order additional testing, if desired, at 1-800-345-GENE.
Specimen Requirements
Specimen
Whole blood or Labcorp buccal swab kit (buccal swab collection kit contains instructions for use of a buccal swab)
Volume
7 mL whole blood or Labcorp buccal swab kit
Minimum Volume
3 mL whole blood or two buccal swabs
Container
Lavender-top (EDTA) tube, yellow-top (ACD) tube, or Labcorp buccal swab kit
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Frozen specimen; hemolysis; quantity not sufficient for analysis; improper container; one buccal swab; wet buccal swab
LOINC® Map
Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
---|---|---|---|---|---|---|
511154 | Factor V Leiden Mutation | 21667-1 | 511155 | Factor V Leiden | 21668-9 | |
511154 | Factor V Leiden Mutation | 21667-1 | 512252 | Reviewed By: | 56850-1 | |
Order Code | 511154 | |||||
Order Code Name | Factor V Leiden Mutation | |||||
Order Loinc | 21667-1 | |||||
Result Code | 511155 | |||||
Result Code Name | Factor V Leiden | |||||
UofM | ||||||
Result LOINC | 21668-9 | |||||
Order Code | 511154 | |||||
Order Code Name | Factor V Leiden Mutation | |||||
Order Loinc | 21667-1 | |||||
Result Code | 512252 | |||||
Result Code Name | Reviewed By: | |||||
UofM | ||||||
Result LOINC | 56850-1 |