Two alternatively spliced 5'BCR/3'JAK2 fusion transcripts in a myeloproliferative neoplasm with a three-way t(9;18;22)(p23;p11.3;q11.2) translocation.

Philadelphia (Ph)-negative myeloproliferative neoplasms (MPNs) are known to harbor alterations of the tyrosine kinase JAK2 (9p24), resulting in the constitutive autoactivation of the encoded protein. Here, we report an unclassifiable MPN case, BCR/ABL1-negative, showing a three-way t(9;18;22)(p23;p11.3;q11.