Novel targeted agents for MPN in development include specific JAK2 inhibitors, histone deacetylase inhibitors, hypomethylating agents, heat shock protein 90 inhibitors, PI3-AKT-mTOR inhibitors, and telomerase inhibitors, all of which, alone or in combination with established therapies, will require assessment of efficacy [3]. The gene discussed is JAK2; the disease is myeloproliferative neoplasm.