jak2-v617f mutation and philadelphia positive chronic myeloid leukemia

jak2 is a tyrosine kinase that plays an important role in the signaling pathways of many hematopoietic growth factor receptors. a single acquired point mutation – v617f – in jak2 occurs in the great majority of patients with polycythemia vera (pv) and approximately half of the patients with idiopathic myelofibrosis (imf) or essential thrombocythemia (et). in contrast, the jak2-v617f mutation is only rarely found in chronic myeloid leukemia (cml) but, recently, some authors have reported the coexistence of jak2v617f and bcr/abl+ in cml patients expressing the p210 bcr–abl oncoprotein. here, we report a cml patient with the expression of p210/b2a2 type bcr–abl transcript and jak2v617f mutation.