X-LINKED RETINITIS PIGMENTOSA

P.I.的长期目标。的研究是为了了解 X连锁视网膜疾病的发病机制。 X连锁视网膜色素变性（XLRP）是一组进行性视网膜色素变性， 退化，具有严重的临床表现和视力丧失， 年轻人 光感受器退化的主要原因不是 知道的 目前无法治疗。 本项目的重点 将对两个XLRP基因（RP 2）的鉴定和表征 和RP 3），其已被定位在Xp11.23-p21.1区域中。 两 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。 在上一个R29赠款期间，我们开发了一个减法- 鉴定候选视网膜或视网膜色素的选择策略 在一些实施方案中，本发明涉及来自XLRP疾病基因座区域的上皮（RPE）cDNA。 的 构建人视网膜、RPE和胎儿眼cDNA文库， 通过有效的基于生物素的 减法 我们正在使用一些策略来选择 来自消减文库的X染色体特异性cDNA。 两个视网膜 已从Xp11.23-p21.1中鉴定出基因（31 A和S3 X67 区域性的。 为了定位克隆，我们分离了酵母人工 染色体（YAC）克隆从XLRP区域通过使用几个标记。 YAC的表征已经鉴定了新的多态性基因座， cDNA克隆。 还启动了研究， 密歇根州XLRP家庭的分析。 利用基因组学方法鉴定疾病基因的补充方法 通过定位克隆的基因组途径和通过分离的cDNA途径 候选的视网膜和RPE基因将在本发明的实施方案期间平行继续。 项目 此外，正在开发新的方法来选择 视网膜cDNA克隆直接来自分选或显微切割的X-基因组 图书馆. 候选基因将从Xp11.23-p21.1 区域，并用于搜索可能负责 治疗疾病 一旦XLRP基因被鉴定， 研究其产品的调节和功能， 疾病发病的分子机制。 的 拟议的研究也可能发现其他X- 相关的视网膜疾病 序列标记位点，多态性标记 和cDNA克隆，在该项目中产生，可能有助于完善 遗传图谱和构建人类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益处。 希望广大 更好的治疗策略设计（包括基因治疗）将 通过对致病基因的鉴定和分析， 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.