Selective pressures from inherited variation impacting myeloproliferative neoplasm initiation

项目摘要/摘要 虽然在描述驱动骨髓增生性疾病的体细胞突变方面取得了实质性进展 肿瘤(MPN)，流行病学研究表明，获得疾病的显著可遗传风险。我们 最近对MPN进行了最大规模的全基因组关联研究，以确定遗传风险变异 促进了这种疾病的获得。我们的初步分析表明，HSC自我调节的作用 通过这些遗传的风险变量进行更新和发挥作用。然而，我们缺乏一个完整的机械性理解。 这些遗传变异产生的选择压力如何促进MPN的收购。在这里，在 在R01中，我们特别想了解遗传风险变量如何提供选择性压力以实现 MPN启动。在这项资助的第一个目标中，我们试图使用严格的老鼠模型来定义一个变体- 含有Gfi1b的HSC选择性增强子可以促进MPN的获取。我们将研究这种增强剂是如何 在天然造血中发挥作用以促进MPN的启动，以及该增强子如何与 这一过程中的体细胞突变。在这笔赠款的第二个目的中，我们试图理解功能丧失是如何 CHEK2可通过偶联原代人类基因组编辑促进MPN的获取和克隆性造血 造血干/祖细胞和全基因组测序以评估这些种系如何遗传 突变可以促进肿瘤的发生。最后，在第三个目标中，我们寻求更全面地定义变量-- 含有调控元件和靶基因可能在HSC的自我更新中发挥作用，并通过 多重引导-互换Cas9基因组编辑方法在原代人类造血干细胞和 祖细胞。总而言之，我们在这笔拨款中提出的研究将为遗传风险如何 变异体可以提供选择压力，使MPN得以出现。

Project Summary/ Abstract While substantial progress has been made to delineate the somatic mutations that drive myeloproliferative neoplasms (MPNs), epidemiologic studies demonstrate a significant heritable risk for disease acquisition. We have recently conducted the largest genome-wide association study of MPNs to define inherited risk variants that promote the acquisition of this disease. Our initial analyses suggest a role for modulation of HSC self- renewal and function by these inherited risk variants. However, we lack a complete mechanistic understanding of how the selective pressures that arise from these inherited variants can promote MPN acquisition. Here, in this R01, we specifically want to understand how inherited risk variants can provide selective pressures to enable MPN initiation. In the first aim of this grant, we seek to use rigorous mouse models to define how a variant- containing HSC-selective enhancer of Gfi1b can promote MPN acquisition. We will study how this enhancer plays a role in native hematopoiesis to promote MPN initiation, as well as how this enhancer can cooperate with somatic mutations in this process. In the second aim of this grant, we seek to understand how loss-of-function of CHEK2 can promote MPN acquisition and clonal hematopoiesis by coupling genome editing of primary human hematopoietic stem/ progenitor cells and whole genome sequencing to assess how such germline genetic mutations can promote oncogenesis. Finally, in the third aim, we seek to more holistically define how variant- harboring regulatory elements and target genes may play a role in HSC self-renewal and function through the use of a multiplexed guide-swap Cas9 genome editing approach in primary human hematopoietic stem and progenitor cells. Collectively, the studies we propose in this grant will provide new insights into how inherited risk variants can provide selection pressures that enable MPNs to arise.