MOLECULAR ANALYSIS OF FRAGILE X SYNDROME

脆性 X 综合征的分子分析

• 批准号: 3330728
• 负责人: David Loren Nelson
• 金额: $ 21.84万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-04-01 至 1997-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3330728
• 关键词: DNA methylation; RNA biosynthesis; autosomal dominant trait; behavior disorders; chromosome translocation; complementary DNA; cytogenetics; developmental genetics; diagnosis design /evaluation; disease /disorder model; embryonic stem cell; fragile X syndromes; gene expression; gene mutation; genetic disorder diagnosis; genetic library; genetic promoter element; genetic transcription; genetically modified animals; genome; human; human population genetics; laboratory mouse; linkage mapping; mental disorders; mental retardation; messenger RNA; model design /development; molecular cloning; molecular genetics; mutant; natural gene amplification; nervous system disorder; nucleic acid repetitive sequence; nucleic acid sequence; oligonucleotides; point mutation; polymerase chain reaction; protein biosynthesis; southern blotting; structural genes; transfection /expression vector

Extensive analysis of the FMR-1 gene and the fragile X mutation site in human Xq27.3 is proposed. This gene is likely to be involved in the phenotypic features of fragile X syndrome, the most common form of inherited mental retardation in humans, with a frequency in boys of approximately 1/1200. Analysis of the spectrum of mutations in fragile X families will provide insight into the very unusual mutational and genetic mechanisms in this peculiar region of the X chromosome. Analysis of the FMR-1 gene and its RNA and protein products will allow determination of its role in normal development. The consequences of defects in this gene and their role in generation of mental retardation will be studied. Understanding the basis of the fragile X phenotype will provide insight into potential therapies, and into the nature of other mental deficiencies. The specific aims of the study are: 1) Characterization of the fragile X mutation site in genomic DNA from patients and other family members; 2) Characterization of the FMR-1 gene located at the fragile X site by definition of its structure, isolation of cDNA representing its mRNA, development of antisera specific to its protein product, and use of these tools to study its expression and presence in tissues from normal and fragile X humans as well as mice at various stages of development; 3) Isolation of the murine equivalent of the FMR-1 gene, characterization of its expression and of the region of the mouse X chromosome for the presence of the peculiar CGG repeat sequence found in humans; 4) Production of a mouse model of fragile X syndrome by gene targeting of the FMR-1 gene in embryonic stem cells and creation of chimeric animals derived from the mutant ES cells; once established, the mouse models will be extensively studied for phenotypic features similar to human fragile X syndrome; 5) Study of the fragile X region for additional genes, and characterization of these for their role (if any) in the syndrome; 6) Identification of other sites in the human genome with long stretches of the CGG repeat sequence, and study of their locations relative to other fragile sites; 7) Analysis of the FMR-1 gene for its role in other, non-fragile X related, mental deficits by mutation detection methods. Characterization of the fragile X mutation and its associated gene will lead to improved diagnosis and provide the capacity to design therapies for this common form of inherited mental retardation. Analysis of the gene should also provide insight into brain function and mechanisms of retardation.

FMR-1基因和脆弱X突变位点的广泛分析 提出了人XQ27.3。该基因可能参与 脆弱X综合征的表型特征，最常见的形式 在人类中遗传的智力低下，男孩的频率 大约1/1200。 分析脆弱x中突变的光谱 家庭将洞悉非常异常的突变和 X染色体这个特殊区域的遗传机制。 分析 FMR-1基因及其RNA和蛋白质产物将允许 确定其在正常发展中的作用。 后果 该基因的缺陷及其在智力低下的产生中的作用 将被研究。 了解脆弱的X表型的基础 提供对潜在疗法的见解，并为其他人的本质提供见识 精神缺陷。 该研究的具体目的是：1） 从基因组DNA中脆弱X突变位点的表征 病人和其他家庭成员； 2）FMR-1基因的表征 通过其结构定义，位于脆弱的X站点，隔离 代表其mRNA的cDNA，特定于其特定的抗血清的发展 蛋白质产物，并使用这些工具来研究其表达和 在正常和脆弱X人类以及小鼠的组织中存在 各个发展阶段； 3）隔离鼠等效的 FMR-1基因的表达和区域的表征 鼠标X染色体，用于奇特的CGG重复 在人类中发现的序列； 4）生产脆弱x的小鼠模型 通过基因靶向胚胎干细胞中FMR-1基因的综合征和 源自突变体细胞的嵌合动物的产生；一次 建立的小鼠模型将被广泛研究以进行表型 类似于人类脆弱X综合征的特征； 5）研究脆弱的x 额外基因的区域，以及它们的作用的表征 （如果有）综合征； 6）识别人类其他地点 CGG重复序列长的基因组，并研究其 相对于其他脆弱位点的位置； 7）FMR-1基因的分析 因为它在其他非fragile x相关的，突变的精神缺陷中的作用 检测方法。 脆弱X突变及其的表征 相关基因将导致诊断的改善并提供能力 为这种常见的遗传智力迟缓设计疗法。 基因的分析还应洞悉大脑功能和 智障机制。