MPL Exon 10 Mutation Detection, Varies

Casandra

Casandra Test Code MC48856Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID MPLVSCPT Code 81339

MPL Exon 10 Mutation Detection, Varies

Clinical Use

Use

DNA sequence variants in exon 10 of the myeloproliferative leukemia virus oncogene (MPL) have been detected in approximately 5% of patients with primary myelofibrosis (PMF) and essential thrombocythemia (ET), which are hematopoietic neoplasms classified within the broad category of myeloproliferative neoplasms. MPL codes for a transmembrane tyrosine kinase, and the most common MPL variants are single base pair substitutions at codon 515. These alterations have been shown to promote constitutive, cytokine-independent activation of the JAK/STAT signaling pathway and contribute to the oncogenic phenotype. Identification of MPL variants can aid in the diagnosis of a myeloproliferative neoplasm and is highly suggestive of either PMF or ET.

Special Instructions

Library of PDFs including pertinent information and forms related to the test are available for additional guidance. If not ordering electronically, complete, print, and send a Hematopathology/Cytogenetics Test Request (T726) with the specimen. Submit only 1 of the following specimens: Peripheral blood, Bone marrow, or Extracted DNA from blood or bone marrow. Avoid sending the specimen in an incorrect tube; use the recommended containers such as Lavender top (EDTA) or yellow top (ACD).

Limitations

A positive result is not specific for a particular diagnosis and clinicopathologic correlation is necessary in all cases. A negative result does not exclude the presence of a myeloproliferative or other neoplasm. Analytical sensitivity is approximately 20%, meaning there must be about 20% of the altered DNA in the specimen for reliable detection. Furthermore, variants outside of exon 10 have not yet been reported.

Test Details

New York Approved