Low V617F Allele Burden in Ph-Negative Chronic Myeloproliferative Neoplasms Is Associated with Additional or Gene Mutations.

(Janus kinase 2) V617F, (Calreticulin) exon 9, and (receptor for thrombopoietin) exon 10 mutations are associated with the vast majority of Ph-negative chronic myeloproliferative neoplasms (MPNs). These mutations affect sequential stages of proliferative signal transduction and therefore, after the emergence of one type of mutation, other types should not have any selective advantages for clonal expansion. However, simultaneous findings of these mutations have been reported by different investigators in up to 10% of MPN cases.