ARUP's Laboratory Test Directory

Prothrombin (F2) G20210A Mutation : 0056060
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Patient History For Molecular Genetic Testing
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Additional Technical Information


Mnemonic: PT PCR

Ordering Recommendation: Order to detect prothrombin G20210A mutation.
Methodology: Polymerase Chain Reaction/Fluorescence Monitoring
Performed: Sun-Sat
Reported: 2-5 days
Specimen Required: Collect: Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

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

Storage/Transport Temperature: Refrigerated.

Stability (collection to initiation of testing): Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Reference Interval:
Negative: This sample is negative for the factor II, prothrombin 20210A mutation.
Interpretive Data: Background Information for Prothrombin (F2) G20210A Mutation:
Characteristics:
The Factor II, G20210A mutation is a common genetic risk factor for venous thrombosis associated with elevated prothrombin levels leading to increased rates of thrombin generation and excessive growth of fibrin clots. The expression of Factor II thrombophilia is impacted by coexisting genetic thrombophilic disorders, acquired thrombophilic disorders (eg, malignancy, hyperhomocysteinemia, high factor VIII levels), and circumstances including: pregnancy, oral contraceptive use, hormone replacement therapy, selective estrogen receptor modulators, travel, central venous catheters, surgery, and organ transplantation.
Incidence:
Approximately 2-5 percent of Caucasians and 0.3 percent of African Americans are heterozygous; homozygosity occurs in 1 in 10,000 individuals.
Inheritance:
Incomplete autosomal dominant.
Penetrance:
The risk of thrombosis is increased 2-4 fold for heterozygotes and further increased for homozygotes.
Cause:
Homozygosity or heterozygosity for F2 c.20210G>A (G20210A).
Mutation Tested:
F2 c.20210G>A (G20210A).
Clinical Sensitivity for Venous Thrombosis
: Approximately 10 percent.
Methodology:
Polymerase chain reaction and fluorescence monitoring.
Analytical Sensitivity and Specificity:
99 percent.
Limitations:
Rare diagnostic errors can occur due to primer site mutations. F2 gene mutations, other than G20210A, will not be detected.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note:
CPT Code(s): 81240
Cross References: Factor II (PT) 20210 Mutation (Prothrombin (F2) G20210A Mutation)