Lab Test

Nucleophosmin 1 Gene Mutation (NPM1)

NPM1 Gene Mutation, NPM1 Mutation, AML, acute myelogenous leukemia

Test Codes

EPIC: LAB6387, Beaker: GNPMG


Molecular Pathology

Specimen Collection Criteria

Collect: Blood OR Bone Marrow.

  • Blood: 10.0 mL whole blood in Lavender-top EDTA tubes or Yellow-top ACD tubes. (Minimum: 5.0 mL)
  • Bone Marrow: 1.0 mL bone marrow aspirate in a Lavender-top EDTA tube. (Minimum: 0.5 mL) 

Physician Office/Draw Specimen Preparation

Do not freeze specimens. Maintain specimens refrigerated (preferred) (2-8°C or 36-46°F) or at room temperature (20-26°C or 68-78.8°F) prior to transport.

Preparation for Courier Transport

Transport: Whole blood or bone marrow at room temperature (20-26°C or 68-78.8°F) or refrigerated (preferred) (2-8°C or 36-46°F).

Rejection Criteria

  • Frozen specimens. 
  • Centrifuged specimens.
  • Mislabeled or unlabeled tubes. 
  • Specimens collected in heparin tubes(Green-top), clot tubes (Red-top), or SST tubes.
  • Specimens not collected and processed as indicated.

Clients will be notified of any cancellations of testing.

In-Lab Processing

Do not freeze specimens. Maintain specimen refrigerated (2-8°C or 36-46°F) prior to testing. 


Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 72 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days

Extracted DNA may be available for additional testing if clinically indicated. Contact the Molecular Pathology Laboratory for verification.


Royal Oak Molecular Pathology Laboratory


Once per week.
Results available in 7-10 days.

Reference Range

Negative (no mutations).

Test Methodology

Polymerase chain reaction (PCR) of genomic DNA with analysis of the products by agarose gel electrophoresis.


This test detects a tetranucleotide insertion in the nucleophosmin 1 (NPM1) gene.

Clinical Utility

The NPM1 mutation is the most frequent single molecular genetic abnormality (46% - 62%) in patients with acute myeloid leukemia with a normal karyotype and is associated with favorable prognosis in the absence of the FLT3 internal tandem duplication (FLT3-ITD). NPM1 mutation positivity is also a marker of the leukemic clone, useful in patient monitoring for residual or recurrent acute myeloid leukemia. As such, the test is recommended at the time of initial diagnosis of AML and to monitor the leukemic clone during therapy.

CPT Codes



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