JAK2 germline genetic variation affects disease susceptibility in primary myelofibrosis regardless of V617F mutational status: nullizygosity for the JAK2 46/1 haplotype is associated with inferior survival

A common JAK2 germline haplotype (46/1) has been associated with JAK2 V617F (VF)-positive myeloproliferative neoplasms. The rs12343867 SNP (C/T) tags this haplotype. A total of 130 patients (77 VF-positive) with primary myelofibrosis (PMF) were analyzed for this informative SNP, using bone marrow-derived DNA. The observed 46/1 C allele frequencies in VF-positive (50%) and VF-negative (36%) patients were both significantly higher than expected in population controls ( P