Mierodisseetion and mieroeloning of chromosomal breast cancer alterations in human

Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1-4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5-8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band- or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10-13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented. Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on "Molecular Genetics in Breast Cancer". Address for correspondence and offprints: Jeffrey M. Trent, Laboratory of Cancer Genetics, National Center for Genome Research, National Institutes of Health, 9000 Rockville Pike, Bldg 49 Rm 4A22, Bethesda MD 20892, USA; Tel: 301-402- 2023; Fax: 301-402-2040