The interaction was also confirmed by acquisition of immunofluorescence images, revealing for the first time that the physical interaction of CHST15 with JAK2 occurs in MPN cells, and suggested that a regulatory signaling axis, the CHST15/JAK2/p-Stat3 axis, is involved in the pathogenesis of familial MPN. The gene discussed is JAK2; the disease is myeloproliferative neoplasm.