CORE--MUTATION DETECTION & CHARACTERIZATION OF TUMOR SUPPRESSOR GENES

该核心的主要功能是肉瘤种类中p53突变的检测和功能表征。这些分析对于项目1、4和5的目标是必不可少的。Strong博士（项目1）使用从该核心获得的数据来表征各种儿童肉瘤患者的过度癌症风险，评估p53种系突变对儿童肉瘤的相对贡献，并确定新生突变的父系起源。此外，由于我们发现了非p53易发癌症的种类，她也将描述这些种类的癌症风险。她进行这些分析的能力取决于确定哪些个体携带p53生殖系突变。该核心获得的数据对于Lozano博士的目标（项目4）也是至关重要的，该目标是在非p53易发癌症的家族中绘制负责癌症易感性的位点，因为对其他家族和个人的识别加强了连锁分析所需的力量。为了确定哪里存在与p53突变相关的明显定量微卫星不稳定表型（项目5，Siciliano博士），确定生殖系p53突变患者显然是必要的。该核心的具体目标是：1) p53编码外显子和侧翼序列拼接连接的渊源者软组织肉瘤,骨肉瘤组确定生殖系p53突变的存在与否2)检查这些样本中p53突变不被上面(1)南部分析来排除可能的总删除一个p53等位基因在肿瘤和3)检查LOH永生的成纤维细胞从LFS,没有患者p53突变4)开发SSCP和麻生太郎方法通过鉴定特异性p53突变筛选家族成员，并在非p53种类中筛选其他已知的肿瘤抑制基因。5)利用酵母功能测定和组织培养细胞瞬时转染实验对p53突变进行功能分析，以记录突变之间的功能差异。这个核心的功能最终将进化为包括其他基因或易患癌症的基因的突变分析（见项目4和核心E）。

The main functions of this core are the detection and functional characterization of p53 mutation in sarcoma kindreds. These analyses are essential for the aims of projects 1, 4, and 5. Dr. Strong (project 1) uses the data obtained from this core to characterize excess cancer risk in kindreds of childhood sarcoma patients, to assess the relative contribution of p53 germline mutations to childhood sarcoma, and to identify paternal origin of de novo mutations. Additionally, since our discovery of non-p53 cancer prone kindreds, she will characterize cancer risk in these kindreds as well. Her ability to do these analyses is dependents of establishing which individuals carry p53 germline mutations. The data obtained by this core are also essential for Dr. Lozano's aim (project 4) to map the locus or loci responsible for cancer predisposition in non p53 cancer prone kindreds since the identification of additional families and individuals strengthens the power needed for linkage analysis. To determiner where there is a distinct quantitative microsatellite instability phenotype associated with p53 mutations (project 5, Dr. Siciliano), it is clearly essential to identify the patients with germline p53 mutations. The specific aims of this core are: 1) to sequence the p53 coding exons and flanking splice junctions from the probands of the soft tissue sarcoma and osteosarcoma cohorts to identify the presence or absence of germline p53 mutations 2) to examine those samples in which a p53 mutation is not identified by (1) above by southern analysis to exclude possible gross deletions of one of the p53 alleles 3) to examine LOH in tumors and immortalized fibroblasts from LFS patients with and without p53 mutations 4) to develop SSCP and ASO methods to screen family members upon identification of the specific p53 mutation and to screen o6ther known tumor suppressor genes in non p53 kindreds 5) to perform functional analyses of p53 mutations using the yeast functional assay and transient transfection experiments in tissue culture cells to document functional differences between mutations. The function of this core will eventually evolve to include mutational analyses of the other gene or genes that predispose to cancer (see project 4 and core E).