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Test Code LAB4314 Factor V Leiden (R506Q) Mutation, Blood

Additional Codes


Test Name in EPIC EPIC Test Code Mnemonic Mayo Test ID


Reporting Name

Factor V Leiden (R506Q) Mutation, B

Useful For

Factor V Leiden mutation testing should be reserved for patients with clinically suspected thrombophilia and: 1) APC-resistance proven or suspected by a low or borderline APC-resistance ratio, or 2) a family history of factor V Leiden.

Method Name

Direct Mutation Analysis

Performing Laboratory

Mayo Medical Laboratories in Rochester

Specimen Type

Whole blood

Specimen Required


Preferred: Yellow top (ACD)

Acceptable: EDTA or sodium citrate

Specimen Volume: Full tube

Collection Instructions: 

1. Invert several times to mix blood.

2. Send specimen in original tube.

Additional Information: Can be combined with other molecular coagulation tests;

-MTHAC 5,10-Methylenetetrahydrofolate Reductase A1298C, Mutation, Blood

-PTNT Prothrombin G20210A Mutation, Blood

-MTHFR 5,10-Methylenetetrahydrofolate Reductase C677T, Mutation, Blood

-MTHP 5,10-Methylenetetrahydrofolate Reductase C677T and A1298C Mutations, Blood

Specimen Minimum Volume

1 mL blood in a 3-mL ACD tube

Specimen Stability Information

Specimen Type Temperature Time
Whole blood Ambient (preferred) 7 days
  Frozen  14 days
  Refrigerated  14 days

Reject Due To


Mild OK; Gross OK


Mild OK; Gross OK




Green top (heparin) tube or Extracted DNA

Reference Values


Day(s) and Time(s) Performed

Monday through Friday; 12 p.m.

CPT Code Information

81241-F5 (coagulation factor V) (eg, hereditary hypercoagulability) gene analysis, Leiden variant


LOINC Code Information

Test ID Test Order Name Order LOINC Value
F5DNA Factor V Leiden (R506Q) Mutation, B 21668-9


Result ID Test Result Name Result LOINC Value
21838 Factor V Leiden (R506Q) Mutation, B 21668-9
21839 F5DNA Interpretation 69049-5
21841 F5DNA Reviewed By 18771-6

Genetics Test Information

Tests for R506Q mutation only.

Clinical Information

Venous thromboembolism includes deep vein thrombosis and its complication, pulmonary embolism. Plasma from 12% to 20% of venous thromboembolism patients is resistant to the anticoagulant effect of activated protein C (APC resistance). Essentially all patients with hereditary APC resistance have a single nucleotide mutation of the coagulation factor V gene (F5 rs6025), which encodes for an arginine (R) to glutamine (Q) substitution at position 506 of the factor V protein (FV R506Q). The factor V Leiden (R506Q) gene mutation test is a direct mutation analysis of patient blood leukocyte genomic DNA.


We recommend the coagulation-based activated protein C (APC)-resistance ratio (mixing with factor V-deficient plasma) as the initial screening assay for APC-resistance. Depending on the assay system, the APC-resistance ratio may be indeterminate for patients with a lupus anticoagulant or extremely high heparin levels.


The interpretive report will include specimen information, assay information, background information, and conclusions based on the test results (normal, heterozygous FV R506Q, homozygous FV R506Q).


This direct mutation analysis will not detect individuals with activated protein c (APC)-resistance caused by mechanisms other than the FV R506Q.


Special Coagulation Clinic and/or Medical Genetics consultations are available for DNA diagnosis cases, and may be especially helpful in complex cases or in situations where the diagnosis is atypical or uncertain.

Method Description

Direct mutation analysis using PCR amplification, signal generation, and release by cleavage of sequence-specific alleles. (Package insert: Invader Factor V, Invader Plus Chemistry, Hologic, Madison, WI)

Analytic Time

3 days

Specimen Retention Time

Whole blood stored 2 weeks

Disease States

  • Factor V Leiden

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.


1. Coagulation Patient Information (T675) in Special Instructions

2. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing form (T576) is available in Special Instructions.

3. If not ordering electronically, complete, print, and send a Coagulation Test Request Form (T753) with the specimen (