PRECLINICAL STUDIES OF ATAXIA-TELANGIECTASIA

一位在AT领域久负盛名的资深研究员提出了 这项工作旨在提高AT的诊断和治疗水平。该提案旨在 了解特定突变与临床的关系 症状。因为多达1%的总人口可能携带 ATM(A-T突变)基因缺陷，这些人可能会妥协 可能占所有癌症患者的5%，希望这些研究将 也为AT-载波提供了更好的诊断。ATM基因很大，有 66个小外显子，从而提出了一个具有挑战性的技术问题 突变筛查。在加州大学洛杉矶分校，加蒂博士有一个独特的细胞库， 来自200多名A-T患者及其家属的mRNAs和DNA。 这一资源使他在位置克隆中发挥了重要作用 这导致了1995年ATM基因的分离。从那时起，大于 已经定义了200种突变；其中一半以上来自 他的实验室。几乎所有这些突变都是通过 利用蛋白质截断试验和构象筛选mRNAs/cdna 灵敏凝胶电泳(CSGE)。加蒂博士将完成 确定cDNA缺陷及其相应的基因组(GDNA)突变 剩余的cDNA及其对另外100名患者的筛查DNA 他的基因还没有得到。加蒂博士将使用限制性内切酶 指纹、化学切割和半自动单链 构象多态筛选方法。他还将参加 测试“智慧型晶片”等新推出产品的效能 筛选技术，以最大限度地减少实际测序量 定义每一种突变所必需的。因为大多数患者都是复合体 杂合子，他的资源应该可以描述400个 突变。Gatti博士还将确定每种类型的受影响单倍型 有耐心，尽可能地在每个家庭内。然后他会比较 每种突变的类型和位置与患者的临床症状 来自多个受影响的家庭和民族，具有创始人效应 突变。具有不同表型的家庭将被研究。加蒂博士 预计他的研究项目最终将有助于定义 这种复杂综合征的基础是单一的共同生物学机制。 基于这种理解，他希望设计一种理性的方法 对受影响的儿童进行有效的治疗。

A well established and senior investigator in the field of AT has proposed this work to improve the diagnosis and treatment of AT. The proposal aims to understand the relationship between specific mutations and clinical symptoms. Because as many as 1% of the general population may carry a defective ATM (A-T mutated) gene, and these individuals may compromise perhaps 5% of all cancer patients, it is hoped that these studies will also offer better diagnosis for AT-carriers. The ATM gene is large, with 66 small exons, thereby presenting a challenging technical problem for mutation screening. At UCLA, Dr. Gatti has a unique repository of cells, mRNAs, and DNAs from greater than 200 A-T patients and their families. This resource allowed him to play a major role in the positional cloning that led to the isolation of the ATM gene in 1995. Since then greater than 200 mutations have been defined; more than half of these have come from his laboratory. Almost all of these mutations have been detected by screening mRNA/cDNA, using a protein truncation test and conformation sensitive gel electrophoresis (CSGE). Dr. Gatti will complete the task of defining cDNA defects and their corresponding genomic (gDNA) mutations on the remaining cDNAs and their screen DNA on 100 additional patients from whom cDNA is not available. Dr. Gatti will use restriction endonuclease finger printing, chemical cleavage, and semi-automated single strand conformational polymorphism screening methods. He will also participate in testing the efficiency of "smart chips" and other newly-introduced screening techniques in order to minimize the amount of actual sequencing necessary to define each mutation. Since most patients are compound heterozygotes, his resources should allow the characterization of 400 mutations. Dr. Gatti will also determine the affected haplotypes for each patient and, whenever possible, within each family. He will then compare the type and site of each mutation with the clinical symptoms of patients from multiple-affected families and ethnic groups with founder effect mutations. Families with variant phenotypes will be studied. Dr. Gatti anticipates that his research project will ultimately help to define the single common biological mechanism that underlies this complex syndrome. Based on this understanding, he then hopes to design a rational approach to an effective therapy of the affected children.