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Test Code
MTHRD
Test Name
MTHFR
CPT Codes
81291
Expected Turnaround Time
6 - 9 days
Clinical Utility

Follow-up evaluation in individuals with hyperhomocysteinemia.
Specimen and Container Info

Specimen Type: Whole Blood

Alternate Specimen Type: Buccal Swab

 

Collection Container: Lavender Top, EDTA

Alternate Collection Container: Yellow Top (ACD) or LabCorp Buccal Swab Kit

 

Desired Specimen Volume: 7 mL
Collection Instructions

Whole Blood

  1. Collect 2 lavender top (EDTA) tubes via venipuncture.

Buccal Swab

  1. Collect buccal swabs following the instructions in the LabCorp buccal swab collection kit.
Processing and Submission Instructions

Whole Blood

  1. Transport 7 mL of whole blood in the original collection containers.

Buccal Swab

  1. Transport buccal swabs utilizing materials provided in the LabCorp buccal swab kit.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

7 days

Refrigerated

7 days
Causes for Rejection
  • Frozen or hemolyzed specimen
  • Quantity not sufficient for analysis
  • Improper container
  • One buccal swab
  • Wet buccal swab
Methodology
Polymerase chain reaction (PCR) and restriction enzyme analysis
Reference Intervals

See patient report.
Limitations

Variants Analyzed: c.665C>T (p. Ala222Val), legacy name: C677T; and c.1286A>C (p. Glu429Ala), legacy name: A1298C. 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.
Alternate Names
  • Hyperhomocysteinemia, C677T and A1298C Mutations
  • Methylenetetrahydrofolate Reductase (MTHFR) Thermolabile Variant, DNA Analysis
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Varies
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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