Ordering Recommendation

Assess genetic risk for thrombosis.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature


Unacceptable Conditions

Frozen specimens in glass collection tubes.


Ambient: 72 hours; Refrigerated: 1 week; Frozen: 1 month


Polymerase Chain Reaction/Fluorescence Monitoring


Mon, Thu


2-7 days

Reference Interval

By report

Interpretive Data

Background Information for Factor XIII (F13A1) V34L Variant:
Characteristics: The Factor XIII (F13A1), V34L sequence variant is a protective factor against pulmonary embolism, deep vein thrombosis, and myocardial infarction in Caucasians.  It may also have a slight protective effect against coronary artery disease. Limited data suggests the V34L sequence variant may also be associated with idiopathic spontaneous subconjunctival hemorrhage (SSH), but this finding has not been confirmed.
Allele Frequency: Caucasian 0.27, African American 0.17, American Indian 0.29, Asian 0.01.
Inheritance: Autosomal dominant.
Cause: Homozygosity or heterozygosity for F13A1; V34L
Variant Tested: F13A1 c.103G>T; p.Val34Leu.
Clinical Sensitivity: Varies by ethnicity.
Methodology: Polymerase chain reaction and fluorescence monitoring.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Mutations in the F13A1 or F13B genes, other than the V34L sequence variant, are not evaluated. Diagnostic errors can occur due to rare sequence variations.
The protective effect of the V34L sequence variant has not been established for ethnicities other than Caucasian and may be altered by other genetic and non-genetic factors not assessed by this assay.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
2003227 Factor XIII (F13A1) V34L Variant
2003228 Factor XIII Variant Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


Factor XIII (F13A1) V34L Variant