Discovering Human Birth Defect Genes from Chromosomal Rearrangements

从染色体重排中发现人类出生缺陷基因

• 批准号: 8053263
• 负责人: RICHARD L MAAS
• 金额: $ 39.62万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-05 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8053263
• 关键词: Affect; Balanced Chromosomal Translocation; Candidate Disease Gene; Chromosomal Rearrangement; Chromosome abnormality; Complex; Congenital Abnormality; Cytogenetics; DNA Sequence Rearrangement; Development; Developmental Gene; Disease; Environmental Risk Factor; Etiology; Eye; Genes; Genetic; Genetic Heterogeneity; Goals; Grant; Health; Human; Human Chromosomes; Human Genetics; Kidney; Laboratories; Link; Maps; Methods; Mus; Mutate; Mutation; Organogenesis; Patients; Phenotype; Provider; Recruitment Activity; Role; System; Testing; Vesico-Ureteral Reflux; cleft lip and palate; cohort; congenital cataract; craniofacial; craniofacial complex; gene discovery; genetic pedigree; interest; outreach; proband

DESCRIPTION (provided by applicant): Although complex diseases represent a critical challenge for human genetics, birth defects represent one class of complex diseases that remain largely unresolved. Because of phenotypic and genetic heterogeneity, the role of environmental factors, and the rarity of extended pedigrees and well-stratified cohorts, birth defects are difficult to study by conventional genetic methods. Nonetheless, the societal burden imposed by birth defects is enormous. This application will take advantage of an efficient, established birth defect gene discovery pipeline that focuses on important birth defects associated with balanced chromosomal rearrangements. In these cases, we will identify genes that are disrupted by the rearrangement breakpoints, and we will test the hypothesis that the genes disrupted by breakpoints are causal for the subject's phenotype. To test the validity of the candidate genes identified, two further strategies will be employed: (1) mutational analysis of phenotypically similar cases that do not involve chromosomal rearrangements, to search for intragenic mutations in the candidate gene, and (2) recapitulation of key aspects of the proband's phenotype in the mouse by targeted mutation or knockdown of the candidate gene. The endpoint for these analyses is to obtain conclusive evidence that the gene disrupted by chromosomal rearrangement in any given case is responsible for the associated birth defects, and to conduct an initial analysis of the gene's developmental function. To accomplish these goals, we will employ a robust accrual system to recruit cases of interest from both national outreach and from major commercial cytogenetic providers. To take maximal advantage of the expertise that already exists within our laboratory, we will restrict our scope to two cases per year (ten overall) and we will focus specifically upon cases that affect organogenesis of the eye, kidney and craniofacial complex. In Aim 1, we will ascertain cases involving balanced chromosomal rearrangements (i.e., translocations and inversions) that are associated with disorders of craniofacial, ocular or renal development, and we will map the rearrangement breakpoints. In Aim 2, we will identify candidate genes disrupted by the breakpoints and determine the relevant mutational mechanisms. In Aim 3, to establish causality for these candidate genes, we will perform mutational analyses of phenotypically related human cases, and in Aim 4 we will further seek to establish causality by using genetic means to recapitulate the phenotype in mouse, and we will also determine the gene's developmental function. This powerful gene discovery approach will identify human genes that are newly linked to medically important birth defects, and help to define their developmental functions. PUBLIC HEALTH REVELANCE: This grant proposes to identify genes that are broken by naturally occurring human chromosome abnormalities associated with congenital birth defects. We will focus on birth defects involving the craniofacial region (e.g., cleft lip and palate), the eye (e.g., congenital cataracts), and the kidney (e.g., vesicoureteral reflux, or VUR). To prove that the broken genes are causally linked to the accompanying birth defect, we will search for mutations in the same gene in other patients with the same birth defect, and we will investigate the consequences of mutating the gene in mice.

描述（由申请人提供）：尽管复杂疾病是人类遗传学的关键挑战，但出生缺陷代表了一类尚未解决的复杂疾病。由于表型和遗传异质性，环境因素的作用以及扩展的血统书和良好分层的同类群体的稀有性，通过常规遗传学方法很难研究出生缺陷。尽管如此，由于先天缺陷施加的社会负担是巨大的。该应用将利用有效的，已建立的先天缺陷基因发现管道，该管道的重点是与均衡染色体重排相关的重要先天缺陷。在这些情况下，我们将确定被重排断点破坏的基因，我们将检验以下假设：被断点破坏的基因是该受试者表型的因果关系。为了测试鉴定出的候选基因的有效性，将采用另外两种策略：（1）对表型相似的情况的突变分析，这些病例不涉及染色体重排，以寻找候选基因中的基因突变，（2）对小鼠在靶标突变的候选物质中的关键方面对小鼠现象中的关键方面进行重新计算。这些分析的终点是获得结论性的证据，表明在任何给定情况下被染色体重排破坏的基因均导致相关的先天缺陷，并对基因的发育功能进行初步分析。为了实现这些目标，我们将采用一个强大的应计系统来招募国家外展和主要商业细胞遗传学提供者感兴趣的案件。为了最大程度地利用我们实验室中已经存在的专业知识，我们将限制每年两例（总体十个），我们将特别关注影响眼睛，肾脏和颅面复合体的器官发生的病例。在AIM 1中，我们将确定涉及与颅面，眼部或肾脏发育障碍有关的均衡染色体重排（即易位和反转）的病例，我们将绘制重排断点。在AIM 2中，我们将确定被断点破坏的候选基因并确定相关的突变机制。在AIM 3中，为了建立这些候选基因的因果关系，我们将对表型相关的人类病例进行突变分析，在AIM 4中，我们将进一步寻求通过使用遗传手段来概括小鼠中表型的因果关系，我们还将确定基因的发育功能。这种强大的基因发现方法将确定与医学上重要的先天缺陷新联系的人类基因，并有助于定义其发育功能。公共卫生的启示：这项赠款提议识别通过与先天性先天缺陷相关的自然人类染色体异常破坏的基因。我们将重点关注涉及颅面区域（例如，唇裂和口感），眼睛（例如，先天性白内障）和肾脏（例如囊泡分流或VUR）的先天缺陷。为了证明破裂的基因与随附的先天缺陷有因果关系，我们将在其他患有相同先天缺陷的患者中寻找同一基因中的突变，我们将研究小鼠中突变基因的后果。