X-LINKED RETINITIS PIGMENTOSA

P.I.S研究的长期目标是了解分子 X-连锁视网膜疾病的发病机制(S)。 X连锁视网膜色素变性(XLRP)是一组进行性视网膜病变 伴有严重临床表现和视力丧失的退行性变 年轻人。光感受器退化的主要原因不是 为人所知。目前还不可能进行治疗。这个项目的重点是 将对两个XLRP基因(RP2)的鉴定和特性进行研究 和RP3)，定位于Xp11.23-p21.1区域。二 候选基因识别和定位的互补策略 克隆将被用来实现这一目标。 在之前的R29拨款期间，我们开发了一个减法- 识别候选视网膜或视网膜色素的选择策略 XLRP病基因座区域的上皮细胞(RPE)cDNA。这个 构建了人视网膜、视网膜色素上皮和胎眼的cDNA文库，并对文库进行了分析 高效生物素为基础的组织特异性基因的富集物 减法。我们使用了许多策略来选择 从消减文库中提取X染色体特异的cDNA。两个视网膜 已从Xp11.23-p21.1中鉴定出31a和S3X67基因 地区性的。对于定位克隆，我们分离了人工酵母 利用多个标记从XLRP区域克隆染色体(YAC)。 YACs的特征已经确定了新的多态基因座和 CDNA克隆。也已经开始了进行连锁的研究 密歇根州XLRP家系的分析。 通过基因识别疾病基因的互补方法 定位克隆的基因组路线和分离的cDNA线 候选的视网膜和RPE基因将在 项目。此外，正在开发新的方法来选择 直接从已分类或显微切割的X基因组中克隆视网膜cDNAs 图书馆。候选基因将从Xp11.23-p21.1中确定 区域，用于搜索可能导致的特定突变 治疗这种疾病。一旦XLRP基因被确定，表达， 将研究其产品的调节和功能，以了解 该病发病的分子机制。这个 拟议中的调查还可能发现其他X-基因的候选基因 相关的视网膜疾病。序列标记的位置、多态标记 而在项目期间产生的cdna克隆可能有助于提炼 基因图谱和构建人类X染色体物理图谱。 受影响家庭的产前诊断和携带者检测 将是拟议研究的早期好处。希望这一天 更好的治疗策略设计(包括基因治疗)将 对致病基因和致病基因进行鉴定和分析。 产品。

The long term objective of P.I.'s research is to understand the molecular mechanism(s) underlying the pathogenesis of X-linked retinal diseases. X-linked Retinitis Pigmentosa (XLRP) is a set of progressive retinal degenerations with severe clinical manifestations and visual loss in young adults. The primary cause of photoreceptor degeneration is not known. No treatment is currently possible. The emphasis in this project will be on the identification and characterization of two XLRP genes (RP2 and RP3) that have been mapped in the Xp11.23-p21.1 region. Two complementary strategies of candidate gene identification and positional cloning will be used to accomplish the goal. During the previous R29 grant period, we developed a subtraction- selection strategy to identify candidate retinal or retinal pigment epithelium (RPE) cDNAs from the region of the XLRP disease loci. The human retina, RPE and fetal eye cDNA libraries were constructed and then enriched for tissue-specific genes by an efficient biotin-based subtraction method. We are using a number of strategies for selecting X chromosome-specific cDNAs from the subtracted libraries. Two retinal genes (31A and S3X67) have been identified from the Xp11.23-p21.1 regional. For positional cloning, we have isolated yeast artificial chromosome (YAC) clones from the XLRP region by using several markers. The characterization of YACs has identified novel polymorphic loci and cDNA clones. Studies have also been initiated to perform linkage analysis in Michigan XLRP families. The complimentary approaches of identifying the disease genes by the genomic route of positional cloning and by the cDNA route of isolating candidate retinal and RPE genes will be continued in parallel during the project. Furthermore, novel methods are being developed to select retinal cDNA clones directly from sorted or microdissected X-genomic libraries. The candidate genes will be identified from the Xp11.23-p21.1 region and used to search for specific mutations that may be responsible for the disease. Once XLRP genes are identified, the expression, regulation and function of their products will be studied to understand the molecular mechanisms of the pathogenesis of the disease. The proposed investigations may also uncover candidate genes for other X- linked retinal diseases. The sequence tagged sites, polymorphic markers and cDNA clones, generated during the project, may help in refining the genetic map and constructing the physical map of the human X-chromosome. Pre- and antenatal diagnosis and carrier detection in affected families will be the early benefits of the proposed studies. It is hoped that the better design of therapeutic strategies (including gene therapy) will follow the identification and analysis of the disease gene and its product.