Paroxysmal dystonic choreoathetosis

EXCEEDTHESPACEPROVIDED。我们将研究阵发性肌张力障碍性舞蹈病（PDC），这是一种遗传性疾病，以自发发生的不自主运动的长期发作为特征，通常在咖啡因或酒精摄入后发生。PDC的病因尚不清楚，治疗方法也不令人满意。我们认为PDC是由离子通道基因突变引起的；或者在编码与中枢神经系统中的离子通道相互作用或调节的因子的基因中。这一预测是基于PDC是一种阵发性疾病这一事实，以及观察到离子通道基因突变是其他13种阵发性神经系统疾病的原因。我们将鉴定和分析PDC基因。我们在chr上发现了PDC位点。2q33-35，将该位点减少到2.7 cM；绘制了这一地区的实体地图；并对该位点的候选基因进行了鉴定和分析。PDC基因座的长度为2.4 Mb，测序量已达到bbbb99 %。已知23个基因与此位点相关。我们完成了其中8个基因的编码序列分析。我们利用计算机分析PDC配置序列来预测转录序列的存在；然后进行RT-PCR，以确定哪些预测基因在大脑中被转录。该分析表明，47个预测基因在大脑中表达。通过自动化DNA测序，我们可以分析所有已知基因的编码序列（合计-200,000 bp），并预测18个月内大脑中表达的基因。为了彻底起见，我们将测定PDC组中剩余1%的DNA序列；并根据需要使用其他基因鉴定方法。在候选基因分析的同时，我们将进一步减少PDC位点（从而减少候选基因的数量）：a)确定我们的五个PDC类群之间是否存在共享的单倍型；B)研究这些种类中的其他个体；C)利用单核苷酸多态性分析精细定位位点间隔；d)研究额外的PDC类型（最近又发现了两种PDC类型）。如果在任何PDC候选基因中未发现疾病特异性编码序列突变，我们将考虑突变涉及基因调控元件的可能性；并分析淋巴细胞mRNA中PDC候选基因的稳态mRNA丰度和大小（无法获得死后脑物质作为mRNA来源）。在确定PDC基因后，我们将通过确定a)其组织特异性基因表达模式来分析该基因的功能；B)细胞内分布；C，与之相互作用的蛋白质；d)在培养细胞和实验室小鼠中引入疾病特异性PDC基因突变的后果（基因敲除和转基因实验）。我们对这些方法都很有经验。确定PDC基因和了解PDC的分子基础将有助于阐明其他运动障碍的原因，如原发性运动障碍、抗精神病药引起的迟发性运动障碍和特发性肌张力障碍；并深入了解酒精和咖啡因的生理学，这通常会导致PDC发作。PERFORMANCSEITE (S) (organizationc、密度、状态)密歇根大学安阿伯市密歇根KEYPERSONNELS ======================================== 节结束 ===========================================

EXCEEDTHESPACEPROVIDED. We will study paroxysmal dystonic choreoathetosis (PDC), an inherited disorder characterized by prolonged attacks of involuntary movements that occur spontaneously and often following caffeine or alcohol consumption. The cause of PDC is unknown and treatments are unsatisfactory. We propose that PDC is due to a mutation in an ion channel gene; or in a gene encoding a factor that interacts with or regulates ion channels in the CNS. This prediction is based on the fact that PDC is a paroxysmal disorder and the observation that ion channel gene mutations are responsible for thirteen other paroxysmal neurologic disorders. We will identify and analyze the PDC gene. We discovered the PDC locus on chr. 2q33-35, reduced this locus to 2.7 cM; created a physical map of this region; and identified and analyzed candidate genes at this locus. The PDC locus spans 2.4 Mb and has been >99% sequenced. 23 genes are known to be mapped to this locus. We completed the coding sequence analysis of eight of these genes. We used computer analysis of the PDC contig sequence to predict the presence of transcribed sequences; and then performed RT-PCR to determine which predicted genes were transcribed in the brain. This analysis indicates that 47 predicted genes are expressed in the brain. With automated DNA sequencing, we can analyze the coding sequence (-200,000 bp combined) of all known genes and predicted genes expressed in the brain within 18 months. To be thorough, we will determine the remaining 1% of DNA sequence of the PDC contig; and use other gene identification methods as needed. In parallel with candidate gene analysis, we will further reduce the PDC locus (and thus decrease the number of candidate genes) by a) determining if there are shared haplotypes between our five PDC kindreds; b) studying additional individuals in these kindreds; c) using single nucleotide polymorphism analysis to fine map the locus interval; and d) studying additional PDC kindreds (two more PDC kindreds were recently identified). If disease-specific coding sequence mutations are not identified in any PDC candidate gene, we will consider the possibility that the mutation involves gene regulatory elements; and analyze steady-state mRNA abundance and size of PDC candidate genes in lymphocyte mRNA (postmortem brain material as a source of mRNA is not available). After identifying the PDC gene, we will analyze the function of this gene by determining a) its tissue specific pattern of gene expression; b) its intracellular distribution; c) the proteins with which it interacts; and d) the consequences of introducing disease-specific PDC gene mutations in cultured cells and laboratory mice (gene knock-out and transgenic experiments). We are experienced with each of these methods. Identifying the PDC gene and understanding the molecular basis of PDC will help elucidate the causes of other movement disorders such as Idnesigenic dyskinesia, neuroleptic induced tardive dyskinesia, and idiopathic dystonia; and provide insight into the physiology of alcohol and caffeine, which typically induce PDC attacks. PERFORMANCSEITE(S)(organizationc,ity,state) The University of Michigan, Ann Arbor, Michigan KEYPERSONNELS ========================================Section End===========================================