Home
HelpTest Code JAKXM JAK2 Exon 12 and Other Non-V617F Mutation Detection, Bone Marrow
Reporting Name
JAK2 Exon 12 Mutation Detection, BMUseful For
Second-order testing to aid in the distinction between a reactive cytosis and a myeloproliferative neoplasm, particularly when a diagnosis of polycythemia is being entertained; for use with bone marrow specimens
Testing Algorithm
This is a second-order test that should be used when the test for the JAK2M / JAK2 V617F Mutation Detection, Bone Marrow test is negative.
See Myeloproliferative Neoplasm: A Diagnostic Approach to Bone Marrow Evaluation in Special Instructions.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
Bone MarrowOrdering Guidance
In all cases being evaluated for JAK2 mutation status, the initial test that should be ordered is JAK2M / JAK2 V617F Mutation Detection, Bone Marrow, a sensitive assay for detection of the mutation. However, if no JAK2 V617F mutation is found, further evaluation of JAK2 may be clinically indicated.
This test is a second-order test that should be ordered when the test for the JAK2M / JAK2 V617F Mutation Detection, Bone Marrow test is negative.
Shipping Instructions
1. Specimen must arrive within 5 days (120 hours) of collection.
2. Draw and package specimen as close to shipping time as possible.
Necessary Information
Date of collection is required.
Specimen Required
Container/Tube:
Preferred: EDTA (lavender top)
Acceptable: ACD (yellow top)
Specimen Volume: 4 mL
Collection Instructions:
1. Invert several times to mix bone marrow.
2. Send specimen in original tube.
Specimen Minimum Volume
2 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Bone Marrow | Refrigerated (preferred) | 5 days | PURPLE OR PINK TOP/EDTA |
| Ambient | 5 days | PURPLE OR PINK TOP/EDTA |
Special Instructions
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
0027U-JAK2 (Janus kinase 2) (eg, myeloproliferative disorder), exon 12 sequence and exon 13 sequence, if performed
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| JAKXM | JAK2 Exon 12 Mutation Detection, BM | 80186-0 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 39468 | JAK2 Sequencing Result | 80186-0 |
| 20250 | Final Diagnosis: | 34574-4 |
Interpretation
The results will be reported as 1 of 2 states:
1. Negative for JAK2 mutation
2. Positive for JAK2 mutation
If the result is positive, a description of the mutation at the nucleotide level and the altered protein sequence is reported.
Positive mutation status is highly suggestive of a myeloproliferative neoplasm, but must be correlated with clinical and other laboratory features for a definitive diagnosis. Negative mutation status does not exclude the presence of a myeloproliferative or other neoplasm.
Clinical Reference
1. Ma W, Kantarjian H, Zhang X, et al: Mutation profile of JAK2 transcripts in patients with chronic myeloid neoplasias. J Mol Diagn 2009;11:49-53
2. Kilpivaara O, Levine RL: JAK2 and MPL mutations in myeloproliferative neoplasms: discovery and science. Leukemia 2008;22:1813-1817
3. Kravolics R: Genetic complexity of myeloproliferative neoplasms. Leukemia 2008;22:1841-1848
Report Available
5 to 8 daysMethod Name
Mutation Detection in cDNA Using Sanger Sequencing
Forms
1. Hematopathology Patient Information (T676) in Special Instructions
2. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen.