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25482 JAK2 V617F with reflex to CALR and MPL (MPNR)

JAK2 V617F with reflex to CALR and MPL (MPNR)
Test Code: MPNRSO
Synonyms/Keywords
83872-JAK2B, Janus kinase 2 gene, Tyrosine Kinase Mutation, CALR Calreticulin Essential Thrombocythemia, JAK2-negative Myeloproliferative Neoplasm, Myelofibrosis, Myeloproliferative Disorder, Myeloproliferative Neoplasm (MPN), Primary Myelofibrosis, MPL S505, MPLW515, Myeloproliferative leukemia virus oncogene
Test Components
​JAK2, V617F,(JAK2B), CALR (CALX), MPL (exon10) (MPLR)
Useful For

Aiding in the distinction between a reactive cytosis and a chronic myeloproliferative disorder

Evaluating for variants in JAK2, CALR, and MPL genes in an algorithmic process

Specimen Requirements
Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​Whole Blood ​Lavender Top Tube (EDTA) ​Yellow Top Tube (ACD solution B) ​3 mL ​0.5 mL
​Bone Marrow ​Lavender Top Tube (EDTA) ​​Yellow Top Tube (ACD solution B) ​2 mL

​0.5 mL

​Extractd DNA from blood or bone marrow ​1.5  to 2 mL tube with indication of volume and concentration of DNA ​Entire specimen
Collection Processing Instructions

The following information is required:
1. Pertinent clinical history
2. Clinical or morphologic suspicion
3. Date of collection
4. Specimen source

Specimen must arrive within 168 hours (7 days) of collection.

Send whole blood or bone marrow specimens in original tube.  Label must indicate sample type.

Specimen Stability Information
Specimen Type Temperature Time
Whole Blood​ ​ Ambient (preferred) ​7 days
​Refrigerate ​7 days
Bone Marrow ​ ​Ambient (preferred) ​7 days
​Refrigerate ​7 days
Extraced DNA from blood or bone marrow​ ​ ​Ambient (preferred) ​7 days
​Refrigerate ​7 days
Rejection Criteria
Gross hemolysis
​Paraffin embedded bone marrow aspirate clot or biopsy blocks, slides, or paraffin shavings
​Moderately to severely clotted
Interference

​A positive result is not specific for a particular subtype of myeloproliferative neoplasm and clinicopathologic correlation is necessary in all cases.

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

In rare cases, a variant other than the V617F may be present in an area that interferes with primer or probe binding and cause a false-negative result.

If this test is ordered in the setting of erythrocytosis and suspicion of polycythemia vera, interpretation requires correlation with a concurrent or recent prior bone marrow evaluation.

Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Clinic Laboratories ​Monday through Friday ​7-10 days ​Point Mutation Detection in DNA using Quantitaive Polymerase Chain Reaction (PCR)
Reference Lab
Test Information

​The Janus kinase 2 gene (JAK2) codes for a tyrosine kinase (JAK2) that is associated with the cytoplasmic portion of a variety of transmembrane cytokine and growth factor receptors important for signal transduction in hematopoietic cells. Signaling via JAK2 activation causes phosphorylation of downstream signal transducers and activators of transcription (STAT) proteins (eg, STAT5) ultimately leading to cell growth and differentiation. BCR-ABL1-negative myeloproliferative neoplasms (MPN) frequently harbor an acquired single nucleotide variant in JAK2 characterized as c.G1849T; p. Val617Phe (V617F). The JAK2 V617F is present in 95% to 98% of polycythemia vera (PV), and 50% to 60% of primary myelofibrosis (PMF) and essential thrombocythemia (ET). It has also been described infrequently in other myeloid neoplasms, including chronic myelomonocytic leukemia and myelodysplastic syndrome. Detection of the JAK2 V617F is useful to help establish the diagnosis of MPN. However, a negative JAK2 V617F result does not indicate the absence of MPN. Other important molecular markers in BCR-ABL1-negative MPN include CALR exon 9 variant (20%-30% of PMF and ET) and MPL exon 10 variant (5%-10% of PMF and 3%-5% of ET). Variants in JAK2, CALR, and MPL are essentially mutually exclusive. A CALR variant is associated with decreased risk of thrombosis in both ET and PMF, and confers a favorable clinical outcome in PMF patients. A triple negative (JAK2 V617F, CALR, and MPL-negative) genotype is considered a high-risk molecular signature in PMF.

Reference Range Information
See report
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
81270 ​1 ​Jak2 V617F variant
81219 ​1 ​CALR Gene Mutation, Exon 9 ​If needed
​81339 ​1 ​MPL exon 10 sequence ​If needed
Synonyms/Keywords
83872-JAK2B, Janus kinase 2 gene, Tyrosine Kinase Mutation, CALR Calreticulin Essential Thrombocythemia, JAK2-negative Myeloproliferative Neoplasm, Myelofibrosis, Myeloproliferative Disorder, Myeloproliferative Neoplasm (MPN), Primary Myelofibrosis, MPL S505, MPLW515, Myeloproliferative leukemia virus oncogene
Test Components
​JAK2, V617F,(JAK2B), CALR (CALX), MPL (exon10) (MPLR)
Ordering Applications
Ordering Application Description
​Clinic Order Manager ​JAK2 V617F w reflx CALR & MPL
​Centricity ​JAK2 V617F w reflx CALR & MPL
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
​Whole Blood ​Lavender Top Tube (EDTA) ​Yellow Top Tube (ACD solution B) ​3 mL ​0.5 mL
​Bone Marrow ​Lavender Top Tube (EDTA) ​​Yellow Top Tube (ACD solution B) ​2 mL

​0.5 mL

​Extractd DNA from blood or bone marrow ​1.5  to 2 mL tube with indication of volume and concentration of DNA ​Entire specimen
Collection Processing

The following information is required:
1. Pertinent clinical history
2. Clinical or morphologic suspicion
3. Date of collection
4. Specimen source

Specimen must arrive within 168 hours (7 days) of collection.

Send whole blood or bone marrow specimens in original tube.  Label must indicate sample type.

Specimen Stability Information
Specimen Type Temperature Time
Whole Blood​ ​ Ambient (preferred) ​7 days
​Refrigerate ​7 days
Bone Marrow ​ ​Ambient (preferred) ​7 days
​Refrigerate ​7 days
Extraced DNA from blood or bone marrow​ ​ ​Ambient (preferred) ​7 days
​Refrigerate ​7 days
Rejection Criteria
Gross hemolysis
​Paraffin embedded bone marrow aspirate clot or biopsy blocks, slides, or paraffin shavings
​Moderately to severely clotted
Interference

​A positive result is not specific for a particular subtype of myeloproliferative neoplasm and clinicopathologic correlation is necessary in all cases.

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

In rare cases, a variant other than the V617F may be present in an area that interferes with primer or probe binding and cause a false-negative result.

If this test is ordered in the setting of erythrocytosis and suspicion of polycythemia vera, interpretation requires correlation with a concurrent or recent prior bone marrow evaluation.

Useful For

Aiding in the distinction between a reactive cytosis and a chronic myeloproliferative disorder

Evaluating for variants in JAK2, CALR, and MPL genes in an algorithmic process

Test Components
​JAK2, V617F,(JAK2B), CALR (CALX), MPL (exon10) (MPLR)
Reference Range Information
See report
For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Clinic Laboratories ​Monday through Friday ​7-10 days ​Point Mutation Detection in DNA using Quantitaive Polymerase Chain Reaction (PCR)
Reference Lab
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
81270 ​1 ​Jak2 V617F variant
81219 ​1 ​CALR Gene Mutation, Exon 9 ​If needed
​81339 ​1 ​MPL exon 10 sequence ​If needed
For most current information refer to the Marshfield Laboratory online reference manual.