2 - 7 days
Test Updated:
Primary Myelofibrosis (PMF)
Essential Thrombocythemia (ET)
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Test Overview
Polymerase chain reaction (PCR) with fragment analysis by capillary electrophoresis. Mutation confirmation by Sanger sequencing is performed on select cases.
CALR gene mutations occur at a frequency of 20-30% in primary myelofibrosis (PMF) and essential thrombocythemia (ET). Testing for CALR mutations can aid in the diagnosis of these myeloproliferative neoplasms. CALR mutations are typically exclusive of the JAK2 V617F mutation and are common (~50-75%) in PMF and ET cases that test negative for JAK2 V617F. The utilization of JAK2 V617F, CALR, and also MPL mutation testing provides detection of a clonal marker in the majority (>85%) of patients with PMF and ET. This CALR mutation test qualitatively detects all CALR exon 9 insertion and deletion mutations to a sensitivity of 2-5% mutant allele.
Interpretive report provided.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect blood or bone marrow in a lavender top tube. Refrigerate and send intact blood or bone marrow specimen within 48 hours of collection. Fresh cell suspensions in RPMI should be refrigerated and sent, preferably within 48 hours. Frozen cell suspensions – preferably frozen with 1 hour of collection – may also be sent frozen on dry ice.
Collect blood or bone marrow in a lavender top tube. Refrigerate and send intact blood or bone marrow specimen within 48 hours of collection. Fresh cell suspensions in RPMI should be refrigerated and sent, preferably within 48 hours. Frozen cell suspensions – preferably frozen with 1 hour of collection – may also be sent frozen on dry ice.
