Association of JAK2 Haplotype GGCC_46/1 with the Response to Onco-Drug in MPNs Patients Positive for JAK2V617F Mutation

JAK2 V617F is a somatic mutation associated with myeloproliferative neoplasm (MPN): polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). In MPNs this mutation is associated with the germline GGCC (46/1) haplotype. Most studies consider the association of the JAK2 haplotypeGGCC_46/1 with some MPNs clinical parameters but no one analyzed the association between JAK2 haplotypeGGCC_46/1 and the onset of onco-drug resistance. Thus, we assessed for JAK2 46/1 haplotype correlation with therapy response in JAK2 V617F positive patients. Patients with MPN, selected by the Hematology Laboratory of “V. Fazzi” Hospital (LE), were analyzed with RLFP-PCR assay with rs10974944 SNP. Most of them had PV (63%) or PMF (61%). Among patients that developed onco-drug resistance, 58% had C/G genotype and only 11% had the G/G allele. No correlation between onco-drug resistance and JAK2 haplotype 46/1 variants emerged. Nevertheless, we observed that G/G allele seems to be related to MPNs evolution to myelofibrosis and to the development of onco-drug resistance clinical parameters (p-value= 0.002449; odd ratio of 3.701209). Thus, although other analyses are required, due to the narrow cardinality of sample, our findings suggest how the G/G allele could be useful for MPNs diagnosis and for the prediction of the disease outcome.