Genetic and Functional Dissection of Congenital Anomalies of the Brain

大脑先天性异常的遗传和功能解剖

基本信息

批准号：
9752755
负责人：
Erica Ellen Davis
金额：
$ 25.04万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2021-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9752755
关键词：
Ablation Affect Anatomy Anencephaly Animal Model Antisense Oligonucleotides Award Bioinformatics Biological Assay Biological Models Birth Brain CRISPR/Cas technology Candidate Disease Gene Cell physiology Clinical Clinical Research Complement Complex Congenital Abnormality Congenital cerebellar hypoplasia Congenital cerebral hernia Congenital neurologic anomalies Counseling Data Defect Development Diagnosis Diagnostic Dideoxy Chain Termination DNA Sequencing Disease Disease model Dissection Embryo Enrollment Etiology Family Fetus Funding Future Genes Genetic Genetic study Genome Genomics Genotype Healthcare Systems Heterogeneity Holoprosencephaly Human Hybrids Image Investigation Karyotype Knowledge Larva Lead Lesion Light Literature Magnetic Resonance Imaging Messenger RNA Microcephaly Modeling Molecular Molecular Diagnosis Mutate Nervous system structure Neuraxis Neurological observations Newborn Infant Nucleotides Optics Organ Orthologous Gene Parents Pathogenicity Phenotype Physicians Physiological Population Genetics Positioning Attribute Pregnancy Prenatal Diagnosis Preventive Process Proteins Recurrence Resolution Risk Schizencephaly Scientist Signal Pathway Structure Syndrome System Technology Testing Therapeutic Translating Translational Research Ultrasonography United States Variant Work Zebrafish base body system brain abnormalities brain malformation causal variant clinical Diagnosis clinical care clinical phenotype exome exome sequencing experience fetal gene discovery genetic analysis genetic disorder diagnosis genetic pedigree genetic variant genome editing genome-wide genomic data human disease human model improved in vivo in vivo Model innovation insertion/deletion mutation knock-down lissencephaly multidisciplinary nervous system development novel outcome forecast perinatal period phenotypic data prenatal prospective rare variant therapeutic target tool zebrafish genome

项目摘要

PROJECT SUMMARY Human brain development remains an incompletely understood process, yet congenital abnormalities of this complex structure affect approximately 3/1,000 pregnancies and more than 2000 newborns annually in the United States, posing a substantial burden on the health care system. Congenital brain abnormalities, hallmarked by vast phenotypic heterogeneity, include but are not limited to holoprosencephaly, schizencephaly, anencephaly, encephalocele, microcephaly, ventriculomegaly, cerebellar hypoplasia, and disorders of cortical development, such as lissencephaly. The paired approach of: (1) prenatal diagnosis using a combination of ultrasound and fetal MRI to characterize aberrant phenotypes; with (2) genetic analysis to determine causal lesions, has greatly improved the ability to accurately counsel families about diagnosis, prognosis, and recurrence risk. More recently, prenatal whole exome sequencing (WES) has been applied in cases of lethal or multiple fetal abnormalities to make a molecular diagnosis that otherwise could not be identified with traditional testing. Pilot data from our group and others using WES show a diagnostic rate of 16- 30% in cases of multiple fetal abnormalities, but only 1-2% in isolated brain abnormalities, indicating a critical need to improve diagnostic capabilities and identify novel genes critical to human brain development. We posit that the overabundance of unresolved fetal cases is in large part due to: (1) a knowledge gap in our understanding of the repertoire of genotypes underlying brain abnormalities with prenatal onset; and (2) limitations of population genetics to establish causality of rare variants in novel candidate genes. Here, two CTSA-funded teams who are at the forefronts of prenatal genetic diagnostics and in vivo zebrafish modeling of human disease, at UNC and Duke, respectively, will team up to overcome the current challenges of diagnosing brain abnormalities with a prenatal onset. We will intersect exome- and genome-wide variation data with experimentally tractable and relevant model systems, zebrafish (Danio rerio). We hypothesize that bioinformatics filters using prenatal WES data will reveal novel candidate genes, which can be applied to a zebrafish model to generate initial discoveries critical to human brain development and translate into improved clinical care. First, we will perform bioinformatic analysis of 10 clinically ascertained fetuses with CNS anomalies and their parents using a tiered filtering strategy; and we will apply this analysis paradigm iteratively to 32 prospectively enrolled fetuses and their families. Second, we will establish relevance of candidate genes to brain development and determine variant pathogenicity using state-of-the-art genome editing and phenotyping tools in zebrafish. Completion of our work will expand our understanding of the molecular processes governing prenatal brain development; establish a clinical-research hybrid platform readily applicable to other anatomical organ defects detectable by fetal imaging; and build a suite of animal models of aberrant CNS development with potential for future use in therapeutic target identification.

项目概要人类大脑发育仍然是一个不完全了解的过程，但这种先天性异常复杂的结构每年影响大约 3/1,000 例妊娠和 2000 多名新生儿给美国医疗保健系统带来沉重负担。先天性大脑异常，以巨大的表型异质性为标志，包括但不限于前脑无裂畸形，脑裂畸形、无脑畸形、脑膨出、小头畸形、脑室扩大、小脑发育不全等皮质发育障碍，例如无脑畸形。配对方法：（1）产前诊断结合超声和胎儿 MRI 来表征异常表型； (2) 遗传分析确定病因病变，大大提高了准确向家人提供诊断建议的能力，预后和复发风险。最近，产前全外显子组测序（WES）已应用于致命性或多发性胎儿畸形病例，以进行分子诊断，否则无法进行分子诊断通过传统测试进行识别。我们小组和其他人使用 WES 的试点数据显示诊断率为 16- 在多个胎儿畸形的病例中，这一比例为 30%，但在孤立的脑部畸形中，这一比例仅为 1-2%，这表明存在严重的胎儿畸形。需要提高诊断能力并识别对人类大脑发育至关重要的新基因。我们假设大量未解决的胎儿案件在很大程度上是由于：（1）我们的知识差距了解产前发生的大脑异常的基因型；和（2）群体遗传学的局限性，无法确定新候选基因中罕见变异的因果关系。在这里，两个 CTSA 资助的团队处于产前基因诊断和斑马鱼体内建模领域的前沿北卡罗来纳大学和杜克大学的人类疾病研究中心将联手克服当前诊断的挑战产前发病的大脑异常。我们将外显子组和基因组范围的变异数据与实验上易于处理的相关模型系统，斑马鱼（Danio rerio）。我们假设使用产前 WES 数据的生物信息学过滤器将揭示新的候选基因，可应用于斑马鱼模型产生对人类大脑发育至关重要的初步发现并转化为改进的临床护理。首先，我们将对10个临床确定的患有中枢神经系统的胎儿进行生物信息分析使用分层过滤策略的异常及其父级；我们将迭代地应用这个分析范式 32 名未来登记的胎儿及其家人。其次，我们将建立候选基因的相关性使用最先进的基因组编辑来促进大脑发育并确定变异致病性斑马鱼的表型分析工具。完成我们的工作将扩大我们对分子的理解控制产前大脑发育的过程；轻松建立临床研究混合平台适用于胎儿成像可检测到的其他解剖器官缺陷；并建立一套动物模型异常的中枢神经系统发育具有未来用于治疗靶标识别的潜力。