Special Instructions
Please direct any questions regarding this test to customer service at 800-345-4363.
Expected Turnaround Time
7 - 12 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Specimen Requirements
Specimen
Whole blood, bone marrow or cell pellet
Volume
3 to 5 mL whole blood or 1 to 2 mL bone marrow
Minimum Volume
3 mL whole blood or 1 mL bone marrow
Container
Lavender-top (EDTA) tube or green-top (sodium heparin) tube
Collection
Submit at room temperature. Indicate date and time of collection on the test request form.
Storage Instructions
Maintain specimen at room temperature. If specimen is to be stored prior to shipment, store at 2°C to 8°C.
Causes for Rejection
Specimen does not meet collection criteria; frozen whole blood, marrow, or cell pellet; leaking tube; clotted blood or marrow; grossly hemolyzed specimen or otherwise visibly degraded; contamination by another specimen; specimens containing suspicious foreign material.
Test Details
Use
MPL (myeloproliferative leukemia virus oncogene homology) belongs to the hematopoietin superfamily and enables its ligand, thrombopoietin, to facilitate both global hematopoiesis and megakaryocyte growth and differentiation. MPL W515 mutations are present in patients with primary myelofibrosis (PMF) and essential thrombocythemia (ET) at a frequency of approximately 5% and 1%, respectively. The S505 mutation is detected in patients with hereditary thrombocythemia.
Limitations
Genomic DNA was purified from the provided specimen. MPL gene regions covering the S505N and W515L/K mutations were subjected to PCR amplification and bidirectional sequencing in duplicate to identify sequence variations. This assay has a sensitivity to detect approximately 10% population of cells containing the MPL mutations in a background of nonmutant cells. This assay will not detect the mutation below the sensitivity of this assay. Molecular-based testing is highly accurate, but, as in any laboratory test, rare diagnostic errors may occur.
Methodology
Polymerase chain reaction (PCR) and DNA sequencing
References
Kilpivaara O, Levine RL. JAK2 and MPL mutations in myeloproliferative neoplasms: Discovery and science. Leukemia. 2008 Oct; 22(10):1813-7. 18754026
Liu K, Martini M, Rocca B, et al. Evidence for a founder effect of the MPL-S505N mutation in eight Italian pedigrees with hereditary thrombocythemia. Haematologica. 2009 Oct; 94(10):1368-1374. 19608689
Pardanani AD, Levine RL, Lasho T, et al. MPL515 mutations in myeloproliferative and other myeloid disorders: a study of 1182 patients. Blood. 2006 Nov 15; 108(10):3472-3476. 16868251
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 489150 | MPL Mutation Analysis | 489151 | MPL Mutation Analysis Result: | 62947-7 | ||
| 489150 | MPL Mutation Analysis | 489152 | Nucleotide Change: | 48004-6 | ||
| 489150 | MPL Mutation Analysis | 489154 | Amino Acid Change: | 48005-3 | ||
| 489150 | MPL Mutation Analysis | 489155 | Background: | 8251-1 | ||
| 489150 | MPL Mutation Analysis | 489167 | Methodology: | 62948-5 | ||
| 489150 | MPL Mutation Analysis | 489157 | References: | 75608-0 | ||
| 489150 | MPL Mutation Analysis | 489158 | Director Review: | 72486-4 |
© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.
CPT Statement/Profile Statement
The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at https://loinc.org/license/. Additional information regarding LOINC® codes can be found at LOINC.org, including the LOINC Manual, which can be downloaded at LOINC.org/downloads/files/LOINCManual.pdf