MOLECULAR STUDIES OF GENOMIC IMPRINTING IN HUMANS

产品说明：（改编自研究者摘要）这是一份修订后的申请，要求竞争性更新研究印迹疾病分子机制的资助。Prader-Willi综合征（PWS）是由染色体15 q11-q13区域的父亲印记基因表达缺失引起的一种破坏性的、复杂的发育和神经行为障碍。研究者和其他人已经在该染色体区域和染色体7 C的同线小鼠区域中定义了一系列父系表达的印记基因。研究人员最近开发了一种新的PWS和Angelman综合征（AS）小鼠模型，其中转基因插入删除了所有PWS/AS同源基因。一个严重的新生儿发育不良，典型的PWS在人类中，发生在父系遗传，但转基因系是由母系传播。该PWS小鼠模型将用于确定哪些基因在PWS中发挥哪些作用，并确定该疾病的生化基础。主要假设是PWS是一种连续基因综合征，具有多个印记基因，这些基因可通过PWS小鼠模型的转基因拯救进行唯一鉴定。本提案的目的是通过由三个特定目的组成的方法从遗传学上剖析PWS和PWS小鼠模型表型的每个组分的印记基因：（1）在PWS小鼠模型中使用PWS相关表型的转基因拯救，以定义每个表型组分的特定基因。利用来自2 Mb PWS区域的不同基因含量的基因组克隆和cDNA克隆的转基因技术将被完成以拯救PWS相关表型：（2）表征被证明负责PWS表型方面的基因的功能;（3）筛选15 q11-q13分子水平无异常的PWS或PWS样患者，或PWS单一表型组分的患者，对于由小鼠模型鉴定的特定表型组分的每个候选基因中的突变。

DESCRIPTION: (Adapted from investigator's abstract) This is a revised application for a competitive renewal of a grant to study the molecular mechanisms of imprinting disorders. Prader-Willi syndrome (PWS) is a devastating, complex developmental and neurobehavioral disorder which results from loss of paternal imprinted gene expression at chromosome 15q11-q13. The investigator and others have defined a series of paternally expressed imprinted genes in this chromosome region and the syntenic mouse region in chromosome 7C. The investigator has recently developed a novel mouse model for PWS, and Angelman syndrome (AS), in which a transgene insertion has deleted all the PWS/AS homologous genes. A severe neonatal failure-to-thrive, typical of PWS in humans, occurs on paternal inheritance, but the transgenic line is maintained by maternal transmission. This PWS mouse model will be used to determine which genes play which roles in PWS, and to define the biochemical basis of the disorder. The main hypotheses are that PWS is a contiguous gene syndrome with multiple imprinted genes contributing to the PWS phenotype, and that these genes can be uniquely identified by transgenic rescue of the PWS mouse model. The goal of this proposal is to genetically dissect the imprinted gene(s) underlying each component of the PWS and PWS mouse model phenotypes by an approach consisting of three Specific Aims: (1) use of transgenic rescue of the PWS-associated phenotypes in the PWS mouse model, in order to define specific genes for each phenotypic component. Transgenic technology utilizing genomic clones of varying gene content from the 2 Mb PWS region, and cDNA clones, will be done to rescue the PWS-related phenotypes; (2) to characterize the function of genes shown to be responsible for phenotypic aspects of PWS; and (3) to screen PWS or PWS-like patients with no known 15q11-q13 molecular abnormality, or those patients with single phenotypic components of PWS, for mutations in each candidate gene for specific phenotypic components identified by mouse models.