ISOLATION OF THE HUNTINGTON'S DISEASE GENE

该项目的长期目标是隔离亨廷顿病 (HD)基因，确定该基因中最常见的导致 疾病，并最终在分子水平上理解突变是如何 该基因座上的等位基因产生了这种疾病的神经病理学 杂合子。物理映射战略的组合将是 用来编制一个非常高分辨率的区域物理地图 大约2.5Mb的DNA，现在看来是定义最狭隘的 疾病基因的位置。这将包括以下几种方法 在这一片段中快速分离和定位许多新的DNA探针 染色体带4p16.3。保留4号染色体的体细胞杂交 从几个重要的HD重组体中分离出 具有广泛的特征。这提供了一种明确的手段 大量多态基因座的单倍型分析将允许更多的 疾病基因的精确定位有待完成。所有的DNA都来自 显示包含HD基因的最小物理区域将被分离 在重叠的粘粒和YAC克隆中。克隆的DNA将被彻底 检查以鉴定可能代表转录的基因组序列 地区。完整的Lengih基因克隆和基因组克隆 HD基因的候选基因将被分离出来，并用于比较 这些基因的结构、序列和在正常人中的表达， HD杂合子和HD纯合子的特异性鉴定 代表最常见的HD突变的改变。取得的成就 对这一目标的认识将最终导致对 正常的HD基因产生并提供了洞察如何存在 突变基因产物紊乱。这一信息有望指向 有可能完全预防症状的发生。

The long term goals of this project are to isolate the Huntington's disease (HD) gene, identify the most common mutation in the gene which causes the disease and, ultimately, understand at the molecular level how a mutant allele at this locus produces the neuropathology of the disease in heterozygotes. A combination of physical mapping strategies will be employed to compile a very high resolution physical map of a region of about 2.5 Mb of DNA which now appears to be the most narrowly defined location of the disease gene. This will include several approaches to rapidly isolate and map many new DNA probes throughout this segment of chromosomal band 4p16.3. Somatic cell hybrids which retain chromosomes 4 from several important recombinants with HD will be isolated and extensively characterized. This provides a means for unequivocal haplotyping of a large number of polymorphic loci which will allow a more precise locilization for the disease gene to be made. All of the DNA from the minimal physical region shown to contain the HD gene will be isolated in overlapping cosmid and YAC clones. The cloned DNA will be thoroughly examined to identify genomic sequences likely to represent transcribed regions. Full lengih cDNA clones and genomic clones representing candidates for the HD gene will be isolated and used to compare the structure, sequence and expression of these genes in normal individuals, HD heterozygotes and HD homozygotes in order to identify a specific alteration which represents the most common HD mutation. The achievement of this goal will eventually lead to an understanding of the function of the normal HD gene produce and provide insight into how the presence of a mutant gene product disorder. This information will hopefully point to possible completely prevent the onset of symptoms.