FUNCTIONAL ANALYSIS OF IMPRINTING MUTATIONS

描述：(改编自申请者摘要)： 染色体15q11-q13的印记过程导致无法切换 在亲本配子发生过程中，与Angelman或 Prader-Willi综合征(AS或PWS)的发生取决于父母的起源 突变的可能性。由于印记突变患者在一种 私家侦探建议的元素控制父亲对母亲的印记 在女性生殖系中切换，而PWS家族在 Snrpn启动子，他建议该启动子控制MAT&>PAT印记开关在 雄性生殖系。这些AS和PWS突变定义了一种假定的印记 中心(IC)。这里提出的研究有三个具体目的要检验 这些假说，通过制造印记突变的小鼠模型：(1) IC转录本的分离和鉴定(PAT&>MAT开关元件， XX生殖系)和Snrpn启动子(MAT；PAT开关元件，XY生殖系)， 测试这些元素在印记转换中的作用；(2)目标 胚胎干细胞中同源重组对小鼠IC的突变 细胞，以最终测试这些元素在 印记转换；(3)检查印记基因的表观类型结果 在IC控制的2Mb区域，在表达和DNA甲基化上， 从遗传的印记突变，并检查表型 效果。

DESCRIPTION: (adapted from Applicant's Abstract): Mutations in the imprinting process in chromosome 15q11-q13 cause failure to switch the imprint of a 2 Mb region during parental gametogenesis, with Angelman or Prader-Willi syndrome (AS or PWS) arising, depending on the parental origin of the mutation. AS imprinting mutation patients have mutations in an element the P.I. suggests controls paternal to maternal (pat >mat) imprint switching in the female germline, while PWS families have mutations in the SNRPN promoter, which he suggests controls mat >pat imprint switching in the male germline. These AS and PWS mutations define a putative imprinting center (IC). The studies proposed here have three specific aims to test these hypotheses, by making mouse models of imprinting mutations: (1) Isolation and characterization of IC transcripts (pat >mat switch element, XX germline) and the Snrpn promoter (mat >pat switch element, XY germline), to test the role of these elements in imprint switching; (2) Target mutations into the mouse IC by homologous recombination in embryonic stem cells, to conclusively test the role hypothesized for these elements in imprint switching; (3) Examine the epigenotypic outcome for imprinted genes in the 2 Mb domain controlled by the IC, on expression and DNA methylation, from inheritance of imprinting mutations, and examine for phenotypic effects.