Polycythaemia Vera among Sudanese Patients with Special Emphasis on JAK2 Mutations

Abstract

Background: In recent years, a somatic point mutation in the Janus Kinase 2 (JAK2) gene (1849 G→T, V617F)<br />has been reported to occur in over 90% of patients with polycythemia vera (PV). Another JAK2 mutation in exon 12<br />had been described and shown capable of activating erythropoietin signaling pathways. Objective: In this study, we<br />aimed to determine the frequency of Jak2 mutations (JAK2V617F and JAK2 exon 12) as well as their relationships<br />with hematological parameters in Sudanese patients with myeloproliferative disorders (MPD). A comparison with<br />findings of published studies from other geographic regions was included. Materials and Methods: From each of<br />a total of 83 polycythaemia patients, six milliliters (ml) of venous blood were collected and processed for molecular<br />analysis and measurement of serum erythropoietin level by enzyme-linked immunoassay (ELISA). The JAK2 V617F<br />mutation was determined using an allele-specific competitive blocker (ACB) -PCR assay and High Resolution Melting<br />(HRM) analysis was applied for the JAK2 exon 12 mutation. Results: According to patients' history and the results<br />for EPO levels, nine (10.7 %) out of 83 patients were found to have secondary polycythaemia and 74 (89.3%) PV. The<br />overall frequency of the 2 JAK2 mutations was 94.6% in our Sudanese PV patients, JAK2V617F being found in 91%<br />and JAK2 exon 12 mutations in 8.1%.Conclusion: In summary JAK2 V617F and JAK2 exon 12 mutations are very<br />common in Sudanese PC cases.