Myeloproliferative disorders (MPDs) are characterized by a clonal expansion of myeloid cells. Over the past two years, the identification of the JAK2V617F mutation in most cases of polycythemia vera (PV) as well as approximately 50% of patients with essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF) has greatly advanced our understanding of MPDs. The JAK2V617F mutation alters the JAK2 tyrosine kinase to confer constitutive activation and affect downstream signaling pathways. Data from mouse models demonstrate that the mutation is sufficient for development of PV, but additional work is needed to better understand how this allele functions in ET and IMF. Regardless of the various pathologies, the JAK2V617F discovery highlights the importance of JAK-STAT signaling in myeloid differentiation and focuses effort on developing a clinically relevant JAK2 inhibitor.

中文翻译：

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JAK2突变在骨髓增生性疾病中的作用。

骨髓增生性疾病（MPD）的特征是髓样细胞的克隆扩增。在过去的两年中，在大多数真性红细胞增多症（PV）以及大约50％的原发性血小板增多症（ET）和特发性骨髓纤维化（IMF）患者中，JAK2V617F突变的鉴定极大地增进了我们对MPD的理解。JAK2V617F突变会改变JAK2酪氨酸激酶，从而赋予组成型激活并影响下游信号通路。来自小鼠模型的数据表明，该突变足以促进PV的发生，但是还需要进行其他工作才能更好地了解该等位基因在ET和IMF中的功能。不管各种病理，