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Methylenetetrahydrofolate Reductase (MTHFR), DNA Mutation Analysis

Additional Codes

Epic LAB000- miscellaneous test then add MTHFR in comments

Performing Laboratory

Quest Diagnostics

Clinical Significance

Methylenetetrahydrofolate Reductase (MTHFR), DNA Mutation Analysis - Reduced methylenetetrahydrofolate reductase (MTHFR) enzyme activity is a genetic risk factor for hyperhomocysteinemia, especially when present with low serum folate levels. Two common variants in the MTHFR gene result in reduced enzyme activity. The "thermolabile" variant C677T [NM 005957.3: c.665C>T (p.A222V)] and A1298C [c. 1286A>C (p.E429A)] occur frequently in the general population. Mild to moderate hyperhomocysteinemia has been identified as a risk factor for coronary artery disease and venous thromboembolism. Hyperhomocysteinemia is multifactorial, involving a combination of genetic, physiologic and environmental factors. Recent studies do not support the previously described association of increased risk for coronary artery disease and venous thromboembolism with mild hyperhomocysteinemia caused by reduced MTHFR activity. Therefore, the utility of MTHFR variant testing is uncertain and is not recommended.

Methodology

Polymerase Chain Reaction and Detection

Specimen Requirements

Preferred Specimen:  5 mL whole blood collected in an EDTA (lavender-top) tube

 

Alternative Specimen(s):  Whole blood collected in: EDTA (royal blue-top), sodium heparin (green-top), ACD solution A or B (yellow-top) tube, or lithium heparin (green-top) tube

 

Minimum Volume:  3 mL

Specimen Transport Temperature

Transport Container:  EDTA (lavender-top) tube

Transport Temperature:  Room temperature

Specimen Stability:  

  • Room temperature: 8 days
  • Refrigerated: 8 days
  • Frozen: 30 days

Day(s) Test Set Up

Set up Daily; Report available: 3-4 days

Reference Values

See Laboratory Report

Test Classification and CPT Coding

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

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