QUANTITATIVE GENETIC STUDY OF SEIZURES

描述(改编自申请人的摘要)： 这项申请要求5年的资金，以确定发挥主要作用的基因 DBA/2在癫痫易感性多因素小鼠模型中的作用 (D2)和C57BL/6(B6)小鼠。在过去的5年里，我们使用了数量性状 基因座(QTL)定位以表征该模型的多基因性质和 记录一种主要遗传效应的存在，称为Szs1，起源于 1号染色体的远端。然后，使用同源菌株，我们缩小了 含有Szs1到一段确定的DNA(3-6 cM)的区域 制定了允许进一步大幅削减规模的战略 在这段关键的时间间隔。因此，此应用程序的主要关注点是 确定Szs1背后的基因。 本提案的具体目标包括：1)延续同源基因 将Szs1临界间隔降低到1-2 cm和 Szs1基因修饰位点的研究；2)分子分析和菌株测序 从关键区间中选择一组候选基因的比较；3) 苏氨酸/丝氨酸多态在老年人中意义的功能研究 钾离子通道候选基因KCNJ10的体外构建 (电生理学)和体内(转基因)实验；4)构建 Szs1关键间隔的物理图。将实现前三个目标 与持续、系统地完善SZS1关键 指导对潜在的癫痫易感基因进行搜索的间隔。 将立即进行功能性KCNJ10研究，并可能重新定向 有计划的策略如果结果提供证据表明K+通道基因 表示Szs1。如果对已知候选基因的分析不能导致 识别Szs1，将构建物理地图并用于发现 新基因，然后可以作为Szs1候选基因进行研究。 总体而言，这套目标代表着过去5年的合理延伸 工作，并相信所提出的同源候选菌株 基因定位克隆策略将导致对一种 对于小鼠来说，癫痫易感基因具有根本性的重要性。希望，这些 调查结果也将带来关于 人类癫痫的发病机制。

DESCRIPTION (adapted from applicant's abstract): This application is requesting 5 years of funding to identify genes that play a major role in a multifactorial mouse model of seizure susceptibility involving DBA/2 (D2) and C57BL/6 (B6) mice. Over the past 5 years, we used quantitative trait locus (QTL) mapping to characterize the polygenic nature of this model and document the presence of a major genetic effect, termed Szs1, originating from the distal portion of chromosome 1. Then, using congenic strains, we narrowed the region that harbors Szs1 to a defined segment of DNA (3-6 cM) with a strategy in place that will allow additional significant reductions in the size of this critical interval. Thus, the prime focus of this application is to identify the gene, which underlies Szs1. Specific Aims of the current proposal include: 1) continuation of congenic strain development for reduction of Szs1 critical interval to 1-2 cM and for study of Szs1 modifying loci; 2) molecular analysis and strain sequence comparison of a select group of candidate genes from the critical interval; 3) functional studies of the significance of a threonine/serine polymorphism in a potassium ion channel candidate gene KCNJ10 including in vitro (electrophysiology) and in vivo (transgenesis) experiments; 4) construction of a physical map of the Szs1 critical interval. The first 3 Aims will be pursued in parallel fashion with continued, systematic refinement of the Szs1 critical interval directing a search for the underlying seizure susceptibility gene. Functional KCNJ10 studies will be undertaken immediately and could redirect planned strategy if results provide evidence that this K+-channel gene represents Szs1. If analysis of known gene candidates does not result in identification of Szs1, a physical map will be constructed and used to discover novel genes, which can then be studied as Szs1 candidates. Overall, this set of Aims represents a logical extension of 5 years of previous work and it is believed that the proposed congenic strain-candidate gene-positional cloning strategy will lead to the identification of a fundamentally important seizure susceptibility gene in mice. Hopefully, these findings will lead as well to new and important information regarding the pathogenesis of human epilepsy.