Frequency of JAK2 gene polymorphisms in myeloproliferative diseases

FREQUENCY OF JAK2 GENE POLYMORPHISMS IN MYELOPROLIFERATIVE DISEASESMyeloproliferative disorders (MPH) are a group of stem-cell diseases characterized by hepatosplenomegaly with proliferation, bone marrow fibrosis and transformation to acute leukemia in various proportions, such as, polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PM) and chronic myeloid leukemia (CML). The information about the pathogenesis, algorithms for diagnosis and new treatment options for BCR / ABL negative chronic MPH?s have been increased with the discovery of JAK2 (Janus kinase 2) exon 14 mutations.In our study, frequency of JAK2 exon 12 and exon 14 gene polymorphisms in patients with BCR / ABL negative MPH were evaluated. The patients admitted to Adnan Menderes University School of Medicine Teaching and Research Hospital and who diagnosed with myeloproliferative disease were recruited to the study, retrospectively. A total of 50 patients consisting of 18 (36%) patients with PV, 26 (52%) patients with ET and 6 (12%) patients with PM were included in the study. The polymorphisms of exon 12 and 14 of JAK2 gene were determined with DNA sequence analysis method using specific primers to exon 12 and 14 with the DNA sequencing device.In our results, there were not any mutations detected in exon 12 and exon 14 (except V617F mutation) in terms of JAK2 gene polymorphisms. There were no mutations in 28 patients (56%). In 22 patients (44%) V617F mutations in exon 14 of JAK2 gene were found positive. Mutation of exon 14 of JAK2 gene (V617F mutation) was found 61.2% in patients with PV, 38.5% in patients with ET and 16.7% in patients with PM.It would be possible to determine presence and incidence of JAK2 gene polymorphisms with longer term studies and larger patient groups. It is important to detect new gene polymorphisms which would contribute to diagnostic criteria.Keywords: JAK2 exon 12, JAK2 exon 14, DNA sequence analysis, myeloproliferative diseases