Somatic mutations in TET2 occur in patients with myeloproliferative neoplasms and other hematologic malignancies. It has been suggested that TET2 is a tumor suppressor gene and mutations in TET2 precede the acquisition of JAK2-V617F. To examine the order of events, we performed colony assays and genotyped TET2 and JAK2 in individual colonies. In 4 of 8 myeloproliferative neoplasm patients, we f...

n engl j med 362;4 nejm.org january 28, 2010 370 180 unselected patients with chronic-phase polycythemia vera or essential thrombocythemia. Among the five patients with IDH mutations, three harbored an IDH1 R132C substitution and two harbored a novel IDH2 R140Q mutation affecting a residue conserved in mouse, yeast, and plant homologues. In Patient 2, an IDH2 R140Q mutation was detected in eryt...

Acute myeloid leukemia (AML) may follow a JAK2-positive myeloproliferative neoplasm (MPN), although the mechanisms of disease evolution, often involving loss of mutant JAK2, remain obscure. We studied 16 patients with JAK2-mutant (7 of 16) or JAK2 wild-type (9 of 16) AML after a JAK2-mutant MPN. Primary myelofibrosis or myelofibrotic transformation preceded all 7 JAK2-mutant but only 1 of 9 JAK...

Recent studies suggested that JAK2V617F mutation is frequent inpatientswithsplanchnic vein thrombosis (SVT) but not in patients with other venous thromboembolic events (VTE). However, whether screening for the JAK2V617F mutation in VTE patients is justified remains unclear. Therefore, we performed a systematic review to assess the frequency of JAK2 mutation in VTE patients and the role of JAK2V...

BACKGROUND & OBJECTIVES The Janus-associated Kinase-2 mutation JAK2 V617F in chronic myeloproliferative disorders (CMPDs) has been described as a frequent genetic event in majority of patients with polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF). Its frequency varies in different populations but there are no data from India. We therefore, looked for JAK...

1. Jones AV, Kreil S, Zoi K, et al. Widespread occurrence of the JAK2 V617F mutation in chronic myeloproliferative disorders. Blood. 2005;160:2162-2168. 2. Levine RL, Wadleigh M, Cools J, et al. Activating mutation in the tyrosine kinase JAK2 in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis. Cancer Cell. 2005;7:387-397. 3. Zhao R, Xing S, Li Z, et al. I...

BACKGROUND We investigated the Janus kinase 2 (JAK2) mutation and its diagnostic value in patients suffering with non BCR/ABL myeloproliferative diseases (nMPD) or other reactive conditions. METHODS We reviewed the clinical records of 83 patients who underwent bone marrow (BM) examinations with suspect of nMPD. The diagnoses of nMPD were made based on the WHO criteria since 2001 and the PVSG ...

Utilizing ENU mutagenesis, we identified a mutant mouse with elevated platelets. Genetic mapping localized the mutation to an interval on chromosome 19 that encodes the Jak2 tyrosine kinase. We identified a A3056T mutation resulting in a premature stop codon within exon 19 of Jak2 (Jak2(K915X)), resulting in a protein truncation and functionally inactive enzyme. This novel platelet phenotype wa...

BACKGROUND/AIMS The diagnosis of an underlying myeloproliferative neoplasm (MPN) is often problematic in patients with Budd Chiari syndrome (BCS) or portal vein thrombosis (PVT). This study aimed to assess the diagnostic value of the JAK2 gene V617F gain-of-function mutation for MPN in splanchnic vein thrombosis patients. MATERIALS AND METHODS One hundred eleven patients (80 with PVT, 27 with...

BACKGROUND AND OBJECTIVE Co-existence of myeloproliferative disorders (MPD) and Janus associated kinase 2 mutation (JAK2 V617F) is a well-established fact. Only few case reports are available showing presence of JAK2 V617F mutation in chronic myeloid leukemia (CML). Purpose of this study was to determine the frequency of JAK2 V617F mutation in Philadelphia Chromosome positive (Ph (+)) CML patie...