Sign in →

Test Code HLX CALR CASE Calreticulin (CALR) Mutation Analysis

Additional Codes

Sunrise Clinical Manager (SCM) Orderable:   Calreticulin Mutation Analysis

AllScripts (AEHR) Orderable:  Calreticulin Mutation Analysis

Performing Laboratory

Northwell Health Laboratories


Polymerase Chain Reaction (PCR) Amplification/Capillary Electrophoresis

Reference Values


Positive : A deletion/insertion-type mutation was detected in CALR, exon 9

A positive result is suggestive of a myeloid neoplasm; however, results must be correlated with other clinical and laboratory findings for definitive diagnosis.


Negative: No deletion or insertion was detected in CALR, exon9

A negative result does not exclude the presence of a myeloproliferative neoplasm or other neoplastic disorders.

This test only detects insertions and deletions (indels) in exon 9 of the CALR gene, single point mutations in this exon or mutations outside exon 9 cannot be detected. However, all reported clinically significant mutations in CALR described to date are due to indels.

Occasionally an "invalid" result is obtained when the DNA extracted from the specimen fails to amplify. Failure can be due to poor DNA quality or the presence of a PCR inhibitor


TAT: 8 Days

Test Classification and CPT Coding

83891 - DNA extract-purify


Physician Office Specimen Requirements

Submit only 1 of the following specimens:



Container/Tube:  Lavender-top (EDTA) tube(s)

Specimen:  3 mL (minimum volume:  1 mL) of EDTA whole blood in original VACUTAINER(S)®

Transport Temperature:  Ambient

Collection Instructions:  Invert several times to mix blood. Forward promptly.
Note:  1. The following information is required on request form for processing:

A. Pertinent clinical history

B. Clinical or morphologic suspicion

C. Draw date

D. Specimen source (blood)

2. Label specimen appropriately (blood).


Bone Marrow
Place 3 mL (minimum volume:  1 mL) of bone marrow in a lavender-top (EDTA) tube(s) and send in original VACUTAINER(S)®. Invert several times to mix bone marrow. Forward promptly at ambient temperature.

Note:  1. The following information is required on request form for processing:

A. Pertinent clinical history

B. Clinical or morphologic suspicion

C. Collection date

D. Specimen source (bone marrow)

2. Label specimen appropriately (bone marrow).

Day(s) and Time(s) Performed

Monday through Friday

Computer Interface Code

PDM #  1763033

Used For


Recent studies have shown that mutations in CALR are the second most common mutation in MPNs. The mutations are due to insertions or deletions in exon 9 of the CALR gene. They are present in 67%-73% of essential thrombocythemia (ET) and 56%-88% primary myelofibrosis (PMF) patients (3). Mutations in the MPL gene are found in ET and PMF cases. They are not found in Polycythemia Vera or JAK2 and MPL negative patients. Patients with CALR-positive MPN appear to have a more benign clinical course than those with a JAK2 or MPL mutation (2, 3, 4).

CALR mutation analysis is a diagnostic molecular marker in ET and PMF. Patients who are suspected of having an MPN and who have tested negative for MPL and JAK2 mutations are suitable for testing (3, 4).



1. Klampfl T, Gisslinger H, Harutyunyan AS, et al: Somatic mutation of calreticulin in myeloproliferative neoplasms. N Engl J Med 2013;369:2379-90

2. Nangalia J, Massie CE, Baxter EJ, et al: Somatic CALR mutation in myeloproliferative neoplasms with nonmutated JAK2. N Engl J Med 2013;369:2391-2405

3. Rumi E, Pietra D, Ferretti V, et al: JAK2 or CALR mutation status defines subtypes of essential thrombocythemia with substantially different clinical course and outcomes. Published online before print December 23, 2013

4. Rotunno G, Mannarelli C, Guglielmelli P, et al: Impact of calreticulin mutations on clinical and hematological phenotype and outcome in essential thrombocythemia. Blood 2014;123:1552-1555