PBX1 may contribute to other hematopoietic cancers also in the absence of genomic alterations, for example, if overexpressed or if expressed in HSCs or MEPs in the presence of other driver mutations, such as the somatic V617F mutation in the JAK2 gene typical of myeloproliferative neoplasm (MPN). Here, JAK2 is linked to myeloproliferative disorder.