Lab Med Online.  2015 Jan;5(1):1-1. 10.3343/lmo.2015.5.1.1.

Frequency and Clinicohematologic Characteristics of MPL W515 Mutations in Patients with Myeloproliferative Neoplasms

• Park SG
• Kim KB
• Lee W
• Ha JS
• Ryoo NH
• Jeon DS
• Kim JR
• Ham JY
• Suh JS
• Kim YK

• KMID: 2312260
• DOI: http://doi.org/10.3343/lmo.2015.5.1.1

Abstract

BACKGROUND
Recently, myeloproliferative leukemia (MPL) W515 mutations have been reported to be molecular markers for myeloproliferative neoplasms (MPNs). We studied the association between MPL W515 mutations and the clinico-hematological features of patients with MPNs.
METHODS
Our study included 154 consecutive patients diagnosed with MPNs (31 had polycythemia vera [PV]; 106, essential thrombocythemia [ET]; and 17, primary myelofibrosis [PMF]). MPL W515 mutations were detected by real-time PCR and direct sequencing methods.
RESULTS
The MPL W515L mutation was found in 4 patients and the MPL W515A mutation was detected in 1 patient. These 5 patients were diagnosed with JAK2 V617F-negative ET, and they accounted for 12.5% of patients with JAK2 V617F-negative ET. The patients with MPL W515-positive ET showed significantly lower hemoglobin levels and WBC counts than did patients with MPL W515-negative ET or JAK2 V617F-positive ET.
CONCLUSIONS
MPL W515 mutation is a useful diagnostic marker for JAK2 V617F-negative MPNs and it is associated with specific hematologic characteristics such as lower hemoglobin levels and WBC counts.

Keyword

Myeloproliferative neoplasm; Essential thrombocythemia; MPL W515; JAK2 protein tyrosine kinase

MeSH Terms

Humans
Janus Kinase 2
Leukemia
Polycythemia Vera
Primary Myelofibrosis
Real-Time Polymerase Chain Reaction
Thrombocythemia, Essential
Janus Kinase 2

Figure

• 

  Fig. 1 Electropherograms of normal control (upper), MPL W515L mutation (middle), and MPL W515A mutation (lower).

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