Genomic duplications in anophthalmia, microphthalmia and coloboma

项目总结 小眼球，无眼症和眼球缺乏症(MAC)是一组严重的眼部表型，其特征是 缩小或缺少眼睛或涉及各种眼部结构的缝隙(洞)。成功的几率 识别MAC光谱的基因诊断仍未完成，这使得新的发现 机制是一个重要的优先事项。拷贝数变异(CNV)是基因组的缺失或复制 可以遗传或作为显性从头变异出现的片段。有越来越多的发展中的 与CNV相关的表型，表明剂量失衡是人类的一个重要因素 疾病。在这一组中，由于许多原因，剂量增益变体的贡献仍然被低估 包括涉及多个基因在内的因素需要进行复杂的功能研究。在这份提案中， 我们将结合我们在MAC和斑马鱼模型方面的专业知识来揭示这些新的机制 令人衰弱的人类表型。我们提出了两种不同剂量增加之间关联的证据 基因组区域，20q11和3q29，具有孤立和综合征MAC，并确定了多个受影响的家系 这两个基因都在我们的队列中。我们将利用我们从受影响的个人那里收集的DNA样本 Mac进一步确定这些区域和其他候选区域对人类疾病的贡献，以及 发现新的致病剂量敏感基因。具体来说，我们将：1)确定驾驶员基因(S)和 S途径通过产生和研究剂量参与20q11剂量变异的表型 斑马鱼id1、bcl2l1和tpx2基因的获得/损失模型，被确定为该区域内的首选候选基因；2) 揭示与3q29剂量变异相关的表型驱动基因(S)和通路(S) 探索斑马鱼rucn、dlg1和/或bdh1基因在患者体内的剂量得失模型 区域；以及3)通过额外的方法发现人类MAC光谱中涉及的关键剂量敏感区域 绘制以前发现的CNV图，以及探索大的队列(760个受影响的样本 个人及其亲属)经过广泛测试但无法解释的MAC家庭，然后解剖 斑马鱼中新的候选区域。该项目的成功完成将在 人类眼睛发育，包括基因组区域/基因和受影响的途径，并产生健壮的动物 这些复杂的人类表型的模型。

PROJECT SUMMARY Microphthalmia, anophthalmia and coloboma (MAC) is a group of severe ocular phenotypes characterized by a reduction in size or absence of the eye or a gap (hole) involving various ocular structures. The success rate for identifying a genetic diagnosis for MAC spectrum remains incomplete, making the discovery of novel mechanisms an important priority. Copy number variations (CNVs) are deletions or duplications of genomic segments that can be inherited or occur as dominant de novo variants. There is a growing list of developmental phenotypes associated with CNVs, indicating that dosage imbalance represents an important factor in human disease. Within this group, the contribution of dosage gain variants remains underappreciated due to many factors including the involvement of multiple genes necessitating complex functional studies. In this proposal, we will combine our expertise in MAC and the zebrafish model to reveal novel mechanisms of these debilitating human phenotypes. We present evidence for the association of dosage gain at two different genomic regions, 20q11 and 3q29, with isolated and syndromic MAC, with multiple affected families identified in our cohort for both loci. We will utilize our extensive collection of DNA samples from individuals affected with MAC to further define the contribution of these and other candidate regions to human disease, as well as to discover novel disease-causing dosage-sensitive loci. Specifically, we will: 1) identify the driver gene(s) and pathway(s) involved in phenotypes associated with 20q11 dosage variation by generating and studying dosage gain/loss models for the zebrafish id1, bcl2l1 and tpx2 genes, identified as top candidates within the region; 2) reveal driver gene(s) and pathway(s) involved in phenotypes associated with 3q29 dosage variation by exploring dosage gain/loss models for zebrafish rubcn, dlg1 and/or bdh1 genes, located in the affected human region; and 3) uncover critical dosage-sensitive regions involved in human MAC spectrum by additional mapping of previously identified CNVs as well as exploring a large cohort (760 samples from affected individuals and their relatives) of extensively tested but unexplained MAC families, followed by dissection of novel candidate regions in zebrafish. The successful completion of this project will identify novel factors in human ocular development, both genomic regions/genes and affected pathways, and generate robust animal models of these complex human phenotypes.