Description: (Applicant's Description) The Cytogenetics Core offers state-of-the-art cytogenetic technology for Cancer Center members. Banding karyotype is available for numerous mammalian species and computer-based karyotyping is provided for human cells. Among the molecular techniques available, fluorescence in situ (FISH) analysis is offered in metaphase and interphase cells for single or multiple DNA targets from a variety of biological specimens. Comparative Genomic Hybridization (for human, mouse and rat specimens) and multicolor karyotyping (Multiplex-FISH) are also available. In addition to the use of commercial probes, the Cytogenetics Core has capability to prepare DNA probes according to the investigator's needs. Scientific and technical support has been provided to Cancer Center members in experimental design of projects and a comprehensive interpretation of the data obtained in the assays is offered. A total of 31 Cancer Center members from 9 distinct Programs (Cell Biology, Tobacco Related Malignancies, Cancer Genetics, Developmental Therapeutics, Hormone Related Malignancies, Immunology and Immunotherapy, Carcinogenesis and Chemoprevention, and Pediatric Oncology), have used this facility from 1996 to 1999. Approximately 50% of the investigators have used the Core for more than a grant-year. On average, more than 1,000 procedures were performed per year, and a dramatic change from classical towards molecular techniques has been observed. The Core has been assisting Cancer Center investigators both in basic and translational aspects of cancer research. The development of new FISH probes, such as the 3p21.31 probe that usually detects deletion in lung carcinomas, the D-FISH AML/ETO probe for diagnosis of residual AML-M2, and the E2A probe for ALL, illustrates the translational focus of projects that make use of the laboratory. Mapping of DNA clones, characterization and analysis of chromosomal evolution of cell lines, identification of subtle heterozygous and homozygous deletions, and detection of gene amplifications are examples of services routinely submitted to the Core.