OBJECTIVETo detect the mutation and single nucleotide polymorphisms of STAT3 gene in the patients with myeloproliferative neoplasms (MPN), and to analyze the correlation between STAT3 gene and the subtypes of MPN.

METHODSA total of 147 patients with MPN were selected, including 28 patients with polycythaemia vera (PV), 46 patients with essential thrombocythemia (ET), 10 patients with primary myelofibrosis (PMF), and 63 patients with chronic myeloid leukemia (CML); and 88 healthy persons were used as normal control. DNA of all cases was extracted from bone marrow or peripheral blood, and JAK2V617F gene mutation was detected by allele-specific PCR, then 23 exons of STAT3 gene were amplified by PCR. Mutation and single nucleotide polymorphism of Rs2293152 of STAT3 gene were identified by DNA sequencing.

RESULTSSTAT3 gene mutation was found in 8 patients with CML. The mutation rate was 12.7%. the missense mutation（S629T）as found in 3 cases, the synonymous mutation was found in 5 cases (Q469Q 3 cases, G618G 2 cases). One case had mutations at the both sites of S629T and G618G. No mutation of STAT3 gene was found in the normal control group. Rs2293152: detection showed that the G allele of CML group was significantly higher than that of normal control, PV, ET and PMF group (P<0.01), suggesting that the patients with Rs2293152 G allele were more likely to develop CML. The C allele of PV, ET and PMF group was significantly higher than that of CML group (P<0.05), suggesting that the patients with Rs2293152 C allele were more likely to develop PV, ET and PMF. The G allele fiequency of JAK2V617F-negative group was significantly lower than that of the normal control and JAK2V617F positive group (P<0.01), suggesting that the Rs2293152 G allele may be a factor protecting against JAK2V617F mutation.

CONCLUSIONIn MPN patients, STAT3 gene is unstable and prone to mutation. The different alleles of the Rs2293152 locus of the STAT3 gene are relates with different subtypes and JAK2V617F-negative MPN.