[The clinical implication of JAK2 mutation expression in patients with myeloproliferative disorders].

OBJECTIVE

To investigate the frequency and clinical implication of JAK2V617F mutation in Chinese patients with myeloproliferative disorders (MPD).

METHODS

Genomic DNA from bone marrow or blood mononuclear cells of 137 cases of MPD was screened with allele-specific polymerase chain reaction (PCR) and JAK2V617F mutation was detected with gel electrophoresis. There were 57 cases with polycythemia vera (PV), 68 with essential thrombocythemia (ET), 12 with idiopathic myelofibrosis (IMF).

RESULT: JAK2V617F mutation was detected in 42 (73.7%) of the 57 patients with PV, 40 (58.8%) of the 68 with ET and 8 (66.7%) of the 12 with IMF. Sequence analysis of PCR products from selected patients confirmed the coexistence of both mutant and wild-type alleles. A higher prevalence was observed in elderly patients with MPD (P < 0.05). Cytogenetic analysis was performed in 115 of the 137 patients. Among the 108 patients with normal karyotype, JAK2V617F mutation was detected in 74 patients (68.5%) as compared with 5 of the 7 patients with karyotypic abnormalities (71.4%).

CONCLUSION

JAK2V617F mutation occurs in a significant percentage of Chinese patients with the myeloproliferative disorders. There is a higher prevalence in elderly patients.