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Test Code 76480004 5, 10-Methylenetetrahydrofolate Reductase C677T, Mutation, Blood

Performing Laboratory

Barnes-Jewish Hospital Laboratory


The assay utilizes the Invader Plus® chemistry manufactured by Hologic for the detection of the MTHFR c.677 C>T (Ala177Val) mutation in genomic DNA (NM_005957 transcript isoform). Invader and allele-specific probes match the mutant and the wild-type alleles and have overlapping 5’-ends that are cleaved upon perfect hybridization to the amplified DNA. The cleaved 5’-end of the primary probes transiently hybridize with a corresponding fluorescence resonance energy transfer (FRET) cassettes triggering the cleavage of the fluorophore from the cassette by the cleavase enzyme and allowing signal release and detection.

Specimen Requirements

Call Barnes-Jewish Hospital Molecular Diagnostics Laboratory at 314-454-8685 for collection instructions.


Forms: Molecular Diagnostics Laboratory Request for DNA Studies-Medical Genetics in Special Instructions.


Specimen Type: Blood

Container/Tube: Lavender top (EDTA)

Specimen Volume: Full tube

Specimen Minimum Volume: 1-2 mL

Collection Instructions: Invert several times to mix blood. Clotted blood is not acceptable.

Additional Information: Specimen cannot be frozen



Day(s) Test Set Up

Turnaround Time:
STAT: Director approval required
Routine: 3 to 7 business days

Test Classification and CPT Coding


Additional Information

For BJH Laboratory Use Only

Alternate Tube:

1 blue-top (sodium citrate) tube or 1 yellow-top (ACD) tube

Analyte Stability:

  Blood is stable 8 hours at ambient temperature, up to 168 hours refrigerated.  

Laboratory Processing Instructions:
Test performed in BJH Molecular Diagnostics.