JAK2 V617F (quantitative)

EDTA Blood, 4ml

Bone marrow or EDTA blood

Chronic myeloproliferative disorders (MPNs) that affect the haematopoietic system include essential thrombocythaemia (ET), polycythaemia vera (PV) and chronic idiopathic myelofibrosis (cIMF). Janus kinase 2 (JAK2), a cytoplasmic tyrosine kinase, is involved in the signalling of haematopoietic growth factors. In approx. 90-95% of patients with PV and in approx. 50-60% of patients with cIMF or ET, the acquired JAK2 point mutation V617F is detectable. This is located in exon 14 of the JAK2 gene and leads to an exchange of the amino acid valine for phenylalanine. This leads to a change in the activity-inhibiting JH2 domain and to activation of the JAK2 tyrosine kinase, which results in an increased division rate of the affected haematopoietic cells.
The majority of patients with polycythaemia vera or primary myelofibrosis have a V617F mutation rate of more than 50%, whereas the opposite has been observed in patients with essential thrombocythaemia (Asp et al., Annals of Hematology, 2018). The quantification of the JAK2 variant V617F can therefore be helpful in differentiating between the various MPN subtypes, but can also be used to monitor the treatment success of new targeted therapies and in transplanted patients.