Mechanisms of modifier effects on aganglionosis in the Sox10Dom model of HSCR

描述（由申请人提供）：先天性巨结肠（HSCR）是一种先天性胃肠道疾病，表现为远端结肠不同部分神经节缺失，原因是神经嵴干细胞（NCSC）缺陷，导致肠神经系统。HSCR是复杂遗传疾病的一个典型例子。HSCR病例通常归因于RET突变，但其他基因（包括SOX 10）的突变也可导致无神经节细胞症。大约50%的HSCR病例病因不明。无神经节细胞症的程度在个体之间差异很大，甚至可以在家庭成员之间存在差异。在HSCR小鼠模型中的研究表明，遗传背景中的修饰基因在决定无神经节细胞症的发病率和严重程度方面起着重要作用。了解修饰剂和基因-基因相互作用，有助于HSCR的变化，将增加对HSCR的复杂性和发病机制的理解。先前的研究已经确定了Sox 10 Dom小鼠在HSCR研究中的效用。这些小鼠重现了在患者中观察到的无神经节细胞症，并已用于鉴定无神经节细胞症的修饰剂。本研究旨在证明一个高度显著的候选基因与Sox 10的相互作用，以影响Sox 10 Dom HSCR模型的无神经节细胞表型，并将确定这种相互作用对肠道NCSC的生物学效应。目的1将使用BAG修饰技术和转基因小鼠品系的产生来证明所鉴定的候选基因的改变水平改变Sox 10 Dom无神经节细胞症的发病率和严重程度。目的2将使用纯化的NCSC的免疫组织化学和培养来确定修饰相互作用对NCSC的迁移、增殖和发育潜力的影响。这项研究的结果将使胃肠病学界更好地了解HCSR的原因以及肠神经系统发育所涉及的生物学过程。最后，Sox 10-修饰剂相互作用的表征将提供深入了解修饰剂如何影响其他复杂疾病。这项研究将增加我们对HSCR遗传基础的理解，帮助确定不可分类疾病患者无神经节细胞症的原因，并增加对肠神经系统发育的了解。

DESCRIPTION (provided by applicant): Hirschsprung disease (HSCR) is a congenital disorder of the gastrointestinal tract that presents as a lack of ganglia in a variable portion of the distal colon due to deficits in the neural crest stem cells (NCSC) that give rise to the enteric nervous system. HSCR is a prime example of a complex genetic disease. Often HSCR cases are attributed to mutations in RET but mutations in other genes, including SOX10, can also cause aganglionosis. Approximately 50% of HSCR cases are of unknown etiology. Extent of aganglionosis varies widely among individuals and can even differ between family members. Studies in mouse models of HSCR demonstrate that modifier genes in the genetic background play a large role in determining both the penetrance and severity of aganglionosis. Understanding modifiers and gene-gene interactions that contribute to variation of HSCR will increase understanding of HSCR complexity and pathogenesis. Previous studies have established the utility of Sox10Dom mice in the study of HSCR. These mice recapitulate the aganglionosis seen in patients and have been used to identify modifiers of aganglionosis. The current study aims to demonstrate the interaction of a highly significant candidate gene with Sox10 to impact the aganglionic phenotype of the Sox10Dom HSCR model and will definite the biological effect of this interaction on enteric NCSC. Aim 1 will use BAG modification techniques and the generation of transgenic lines of mice to demonstrate that altered levels of the identified candidate gene modify the penetrance and severity of Sox10Dom aganglionosis. Aim 2 will use both immunohistochemistry and culture of purified NCSC to determine the effect of the modifying interaction on migration, proliferation, and developmental potential on NCSC. The results of this study will provide the gastroenterology community with a greater understanding of the causes of HCSR as well as the biological processes involved in the development of the enteric nervous system. Finally, characterization of the Sox10-modifier interaction will provide insight into how modifiers influence other complex diseases. This research will increase our understanding of the genetic basis of HSCR, help identify causes of aganglionosis in patients with non-classifiable disease, and increase knowledge of enteric nervous system development.