TEST NAME
– CALR Mutation
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ABOUT TEST
– Most patients with essential thrombocythemia or primary myelofibrosis which was not associated with a JAK2, BCR-ABL or MPL variation, carried a somaticmutation in the CALR gene. The most common mutations were present in exon 9 of the gene. The clinical course in these patients was more indolent than that in patients with the JAK2 V617F mutation Patients with myeloproliferative neoplasms carrying CALR mutations presented with higher platelet counts and lower hemoglobin levels than patients with mutated JAK2. Mutations of CALR have been detected in hematopoietic stem and progenitor cells. Clonal analyses showed CALR mutations in the earliest phylogenetic node, a finding consistent with its role as an initiating mutation in some patients Over- expression of the most frequent CALR deletion caused cytokine-independent growth in vitro owing to the activation of signal transducer and activator of transcription 5 (STAT5) by means of an unknown mechanism. Patients with mutated CALR had a lower risk of thrombosis and longer overall survival than patients with mutated JAK2. Initial studies indicate as a proof of principle that cells overexpressing mutant CALR are sensitive to the JAK inhibitor Fedratinib This response has been established on the basis of a reduction in splenomegaly in patients who suffer from Myelofibrosis
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GENES TESTED
–
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SAMPLE REQUIREMENTS
– EDTA
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TAT
– 17
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Related Tests
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