Molecular Genetics of X-linked Cataracts

X连锁白内障的分子遗传学

• 批准号: 6898156
• 负责人: KRISTEN M HUANG
• 金额: $ 39.84万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6898156
• 关键词: artificial chromosomes; cataract; congenital eye disorder; disease /disorder model; gene expression; gene mutation; gene targeting; genetic screening; genetically modified animals; informatics; laboratory mouse; linkage mapping; molecular cloning; molecular genetics; northern blottings; nucleic acid sequence; polymerase chain reaction; sex linked trait; southern blotting

DESCRIPTION (provided by applicant): Congenital cataracts, clinically defined as the presence of cataracts at birth, are the result of mutations in genes that are required for proper lens development. The primary objective of this proposal is to identify the gene defective in the human X-linked cataract dental (XLCD) syndrome, a type of congenital cataract associated with microcornea and dental anomalies. Based on phenotype and location on the X chromosome, the Xcat mouse is the best animal model for human XLCD. We have positionally mapped Xcat through an interspecific backcross and identified two markers Dx Was3 I and DxPas18 that show no recombination with Xcat. Yeast artificial chromosome (YAC) and bacterial artificial chromosome (BAC) libraries were screened with these markers to develop a 900kb contig map of the Xcat critical region. The Xcat critical region will be refined through BAC transgenic complementation experiments designed to identify a single BAC that contains the Xcat gene. We will obtain the sequence of this BAC and analyze it for potential transcription units and ex Candidate Xcat genes will be screened for expression in the lens and by Southern zoo blots and database searches for conservation across species. Candidate genes that are conserved and expressed in prenatal lens will be evaluated for expression in Xcat mice. They will also be evaluated for mutations in the Xcat cDNA. The correlation between the mutant Xcat gene and the cataract phenotype will be confirmed by targeted disruption of Xcat in transgenic animals. Finally, the normal mouse Xcat sequence will be used to clone the corresponding normal human gene. After determining the structure of the normal XLCD gene, XLCD patients will be examined to determine if mutations in the Xcat human homolog are present. Identifying the XLCD gene would contribute to our understanding of the molecular events involved in lens development.

描述（由申请人提供）：先天性白内障，临床定义 由于白内障的存在是基因突变的结果 适当的晶状体开发所必需的。这是这个的主要目标 建议是确定人类X连锁白内障中缺陷的基因 牙科（XLCD）综合征，一种与之相关的先天性白内障 MicroCORNEA和牙科异常。基于X上的表型和位置 染色体，XCAT小鼠是人XLCD的最佳动物模型。我们有 将XCAT映射到XCAT，通过种间反向交叉，并确定了两个 标记DX WAS3 I和DXPAS18与XCAT没有重组。酵母 人造染色体（YAC）和细菌人造染色体（BAC）库 用这些标记筛选以开发XCAT的900kb重叠曲格图 关键区域。 XCAT临界区域将通过BAC进行完善 转基因互补实验旨在识别单个BAC 包含XCAT基因。我们将获得该BAC的序列并分析它 对于潜在的转录单元和EX候选XCAT基因将筛选 在镜头中的表达以及通过Southern Zoo印迹和数据库搜索 跨物种的保护。保守和表达的候选基因 在产前晶状体中，将评估XCAT小鼠的表达。他们也会 在XCAT cDNA中评估突变。突变体之间的相关性 XCAT基因和白内障表型将通过靶向破坏确认 转基因动物中的XCAT。最后，鼠标XCAT序列将是 用于克隆相应的正常人基因。确定 正常XLCD基因的结构将检查XLCD患者以确定 如果存在XCAT人类同源物中的突变。识别XLCD基因 将有助于我们理解镜头中涉及的分子事件 发展。