K Roth1, G Wolf, M Dietel, I Petersen. 1. Institute of Pathology of Charité, Medical School, Humboldt University of Berlin, Germany.
Abstract
OBJECTIVE: To describe the image processing and analysis techniques we developed for the quantitative analysis of comparative genomic hybridization (CGH). STUDY DESIGN: A system for CGH cytometry is based on a semiautomated karyotyping program using the Windows graphic user interface. RESULTS: After alignment and normalization of the fluorescence images of the test genome (FITC) and reference genome (TRITC), the chromosomes are segmented and arranged as a CGH karyogram. The CGH karyograms from different metaphases of one tumor sample are represented as a CGH sum karyogram. Mean DAPI, FITC, TRITC and RATIO images, as well as ratio profiles with the 95% confidence interval, can be displayed. CONCLUSION: Representation of CGH results in the form of pseudocolored mean ratio chromosomes enhances the visibility of the method. The ratio profile plus confidence interval facilitates the identification of preparation artifacts and the classification of chromosomal imbalances. The sum karyograms of several tumors can be combined into a CGH superkaryogram of a tumor subgroup; that helps identify recurrent DNA changes in a tumor and might lead to genetic tumor classification based on CGH.
OBJECTIVE: To describe the image processing and analysis techniques we developed for the quantitative analysis of comparative genomic hybridization (CGH). STUDY DESIGN: A system for CGH cytometry is based on a semiautomated karyotyping program using the Windows graphic user interface. RESULTS: After alignment and normalization of the fluorescence images of the test genome (FITC) and reference genome (TRITC), the chromosomes are segmented and arranged as a CGH karyogram. The CGH karyograms from different metaphases of one tumor sample are represented as a CGH sum karyogram. Mean DAPI, FITC, TRITC and RATIO images, as well as ratio profiles with the 95% confidence interval, can be displayed. CONCLUSION: Representation of CGH results in the form of pseudocolored mean ratio chromosomes enhances the visibility of the method. The ratio profile plus confidence interval facilitates the identification of preparation artifacts and the classification of chromosomal imbalances. The sum karyograms of several tumors can be combined into a CGH superkaryogram of a tumor subgroup; that helps identify recurrent DNA changes in a tumor and might lead to genetic tumor classification based on CGH.
Authors: A Schwendel; F Richard; H Langreck; O Kaufmann; H Lage; K J Winzer; I Petersen; M Dietel Journal: Br J Cancer Date: 1998-09 Impact factor: 7.640