Analysis of JAK2V617F mutation in Jordanian patients with myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) are heterogeneous clonal bone marrow stem cell disorders and include polycythemia vera (PV), essential thrombocythemia (ET), and idiopathic myelofibrosis (IMF) neoplasia. In 2005, the JAK2(V617F) mutation was identified in Philadelphia chromosome-negative patients. The aim of this study was to sequence coding exons 12 and 14 of the JAK2 gene in Jordanian patients with MPN.

Both exons 12 and 14 of the JAK2 gene were amplified using polymerase chain reaction from DNA extracted from 68 blood and bone marrow samples belonging to 57 MPN patients and subjected to DNA sequencing.

JAK2(V617F) mutations were detected in 26 of 57 Jordanian patients (45%) with different MPNs. JAK2(V617F) was identified in 70%, 31%, and 14% of PV, ET, and IMF cases, respectively. Five men diagnosed with PV were homozygous for JAK2(V617F), whereas the other 21 patients were heterozygous for the mutation. Neither the JAK2(V617F) mutation nor any DNA polymorphism in exon 12 or exon 14 of the JAK2 gene was detected among the 40 leukemic patients. A rare single nucleotide polymorphism, c.1860C→T (rs375442615), was detected in one patient with ET.

This study is the first molecular investigation of the JAK2 gene in Jordan. We successfully identified the JAK2(V617F) mutation in Jordanian patients with Philadelphia chromosome-negative MPNs. Our results provide a basis for the early detection of this mutation and simplify the diagnostic workup for these disorders at the molecular level.