MAPPING AND CLONING THE 17Q-LINKED BREAST CANCER LOCUS

乳腺癌易感等位基因的定位 染色体17q是第一个成功定位常见癌症的图谱。这个 这项提议的目标是克隆并在基因上描述这17q 乳腺癌易感基因座。就像将常见疾病本地化一样 已被证明是困难和容易出错的， 随后的精细结构作图和基因分离将会更多 比稀有的孟德尔特征还难。的独特之处在于 用于基因分析的犹他州人口将是 这个项目。我们的项目将是众多项目中的一个 科学联盟共同提供必要的资源 17q易感基因座分析。这是成功的关键 项目是识别大的信息量大的家族以进行地图绘制的能力 学习。信息丰富的亲人很有可能 将研究乳腺癌易感性的分离。联动 分析将确定一个亲属的易感性是否与 17q.一张信息量很大的标志物地图将围绕 易感基因座。我们已经确定了侧翼的重组体 乳腺癌易感基因和一个混合小组的特征 由K.Fournier创建，基因周围有断裂点。一条宇宙线 图书馆将由Fournier杂交种构建，包含10%到10% 15兆碱基的人类DNA，包括包含该基因的区域。 在候选基因内进行遗传和物理映射的克隆 区域被用作成核点以形成区域的重叠群。 最终产品将是一个YAC重叠群，一个稀有的脉冲场图谱 切割者，以及具有遗传边界的区域的粘粒重叠 定义了敏感点必须位于的候选区域。 我们已经排除了7个潜在的候选基因(EDBH17，ERB B2，HOX2， NM23、WNT3、RARA和Prohibitin)；因此，它是 几乎可以确定易感基因是一种新的基因。克隆人 从cDNA文库中衍生的将通过消减来选择 杂交，将cDNA杂交到亲和柱，以及直接 粘粒克隆与cdna克隆的杂交。所有的cDNA都将是 一次筛查病例和对照之间的DNA序列差异 定义了内含子-外显子边界。我们将对表型进行表征 17q连锁的易感基因座对其位置和 特定于年龄的外显度。我们将研究偏侧性的问题。 并尝试确定任何组织病理学特征 与17q相关的乳腺癌。有关生育史的数据将是 将评估收集到的易感基因及其与易感基因的相互作用。 如果在这项研究过程中发现了17q基因，我们将 筛选每个家族中的突变，并对所描述的分析进行分层 在特定突变的基础上。

The localization of a susceptibility allele for breast cancer to chromosome 17q is the first successful mapping of a common cancer. The goal of this proposal is to clone and genetically characterize this 17q breast cancer susceptibility locus. Just as localizing common diseases to a specific chromosome has proven to be difficult and error-prone, the subsequent fine structure mapping and gene isolation will be more difficult than for rare mendelian traits. The unique characteristics of the Utah population for genetic analysis will be an essential asset for this project. Our project will be one of many tied together in a scientific consortium jointly providing the resources necessary for the analysis of the 17q susceptibility locus. A key to the success of this project is the ability to identify large informative kindreds for mapping studies. Highly informative kindreds with a high likelihood of segregating a breast cancer susceptibility will be studied. Linkage analysis will determine whether a kindred's susceptibility is linked to 17q. A map of highly informative markers will be developed around the susceptibility locus. We have identified recombinants which flank the breast cancer susceptibility locus and characterized a hybrid panel created by K. Fournier with breakpoints surrounding the gene. A cosmid library will be constructed from a Fournier hybrid which contains 10 to 15 megabases of human DNA including the region containing the gene. Clones which map genetically and physically within the candidate gene region are used as nucleation points to develop a contig of the region. The final product will be a YAC contig, a pulsed field map of rare cutters, and a cosmid contig of the region with genetic boundaries defining the candidate region where the susceptibility locus must lie. We have eliminated seven potential candidate genes (EDBH17, ERB B2, HOX2, NM23, WNT3, RARA, and Prohibitin) from the region; therefore, it is virtually certain that the susceptibility locus is a novel gene. Clones derived from cDNA libraries will be selected by subtractive hybridization, hybridization of cDNAs to an affinity column, and direct hybridization of cosmid clones to cDNA clones. All cDNAs will be screened for DNA sequence differences between cases and controls once intron-exon boundaries are defined. We will characterize the phenotypic effect of the 17q-linked susceptibility locus in terms of its site and age-specific penetrance. We will examine questions of laterality of disease and try to identify any histopathologic features characteristic of 17q-linked breast cancer. Data on reproductive history will be gathered and interaction with the susceptibility locus will be assessed. If, during the course of this study the 17q gene is identified, we will screen for mutations in each family and stratify the analyses described on a mutation-specific basis.