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"nJAK2 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.

Background and objectives: JAK2 is a nonreceptor tyrosine kinase that plays a major role in myeloid disorders. JAK2V617F mutation is characterized by a G to T transverse at nucleotide 1849 in exon 12 of the JAK2 gene, located on the chromosome 9p, leading to a substitution of valine to phenylalanine at amino acid position 617 in the JAK2 protein. In this study we compared two molecular methods namely ARMS-PCR and AS-PCR for the evaluation of JAK2V617F mutation in patients with myeloproliferative neoplasms. Material and methods: In this study we evaluated JAK2 mutation in 89 patients with Myeloproliferativeneoplasm (MPNs) by simple randomized sampling. The mutation was detected by ARMS-PCR and AS-PCR in patients.Three DNA samples were sequenced for conformation of the above techniques. Results: The JAK2 V617F mutation was detected in 86.6% (26/30) of patients with polycythemia vera and 61.5% (8/13) of patients with idiopathic myelofibrosis. None of 31 CML patients were detected by ARMS-PCR and AS-PCR. In essential thrombocythemia using ARMS-PCR and AS-PCR 46.6% (7/15) and 53% (8/15) of patients were positive, respectively. The mutation was confirmed by sequencing. Conclusions: The results of the study showed that similarity with other studies by two techniques and detection of the JAK2V617F mutation may depend on the molecular technique used. Also, JAK2 mutation detection is an appropriate tool for differential diagnosis of non-CML myeloproliferative neoplasms from benign condition like reactive erytrocytosis and thrombocytosis.

Background: Myeloproliferative neoplasms (MPNs) are clonal malignant diseases that represent a group of conditions including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The aim of this study was to evaluate possible correlations between JAK2V617F allele burden and clinicohematologic characteristics in Iranian patients with MPNs. We also aimed at determining the correlation between JAK2V617F allele burden and use of cyto reductive treatment (hydroxyurea). Materials and Methods: We performed ARMS-PCR for all MPNs samples and subsequently performed real-time quantitative polymerase chain reaction (qRT-PCR) for JAK2V617F allele burden measurement using DNA from peripheral blood leukocytes. Results: Two distinct groups of patients were examined at a single time point: group A (n=40; 20 PV, 20 ET) was examined at the time of diagnosis; group B (n=85; 40 PV, 30 ET and 15 PMF) while under treatment with hydroxyurea (HU). The median allele burden of the JAK2 V617F was 72% for PV and 49% for ET patients at the time of diagnosis (p=0.01). For patients with HU treatment, we determined the median JAK2V617F allele burden to be 43%, 40%, and 46.5 % in PV, ET and PMF patients; respectively. HU-treated PV patients had a significant lower %JAK2V617F than PV patients at the time of diagnosis (43% vs. 72%, p=0.005). In ET group, the relationship between the JAK2 V617F allele burden and leukocyte count was significant (p=0.02 and p=0.01 in untreated and treated patients, respectively). Conclusions: Our results showed that patients with PV have a higher JAK2V617F allele burden. Moreover, our study demonstrated that the JAK2V617F allele burden correlates with clinical features in ET group. We also showed hydroxyurea can affect the JAK2V617F allele burden in PV patients.

"nBackground and objectives: JAK2 is a nonreceptor tyrosine kinase that plays a major role in myeloid disorders. JAK2V617F mutation is characterized by a G to T transverse at nucleotide 1849 in exon 12 of the JAK2 gene, located on the chromosome 9p, leading to a substitution of valine to phenylalanine at amino acid position 617 in the JAK2 protein. In this study we compared two molecular methods namely ARMS-PCR and AS-PCR for the evaluation of JAK2V617F mutation in patients with myeloproliferative neoplasms. "nMaterial and methods: In this study we evaluated JAK2 mutation in 89 patients with Myeloproliferativeneoplasm (MPNs) by simple randomized sampling. The mutation was detected by ARMS-PCR and AS-PCR in patients.Three DNA samples were sequenced for conformation of the above techniques. "nResults: The JAK2 V617F mutation was detected in 86.6% (26/30) of patients with polycythemia vera and 61.5% (8/13) of patients with idiopathic myelofibrosis. None of 31 CML patients were detected by ARMS-PCR and AS-PCR. In essential thrombocythemia using ARMS-PCR and AS-PCR 46.6% (7/15) and 53% (8/15) of patients were positive, respectively. The mutation was confirmed by sequencing. "nConclusions: The results of the study showed that similarity with other studies by two techniques and detection of the JAK2V617F mutation may depend on the molecular technique used. Also, JAK2 mutation detection is an appropriate tool for differential diagnosis of non-CML myeloproliferative neoplasms from benign condition like reactive erytrocytosis and thrombocytosis.