COAMPLIFICATION ON CHROMOSOMES 7P12-13 AND 9Q12-13 IDENTIFIED BY REVERSE CHROMOSOME PAINTING IN A GLIOBLASTOMA-MULTIFORME

DNA amplification is known to occur in approximately 50% of glioblastomas, with the epidermal growth factor receptor(EGFR) gene being the most frequently amplified. Whereas previous amplification studies have largely been limited to the analysis of known tumor-related genes, reverse chromosome painting allows us to search for as yet unidentified amplified domains. Here, we report the analysis of a glioblastoma multiforme by reverse chromosome painting. Hybridization signals were found on chromosome 7p12-13 and chromosome 9q12-13. Standard Southern blot analysis revealed amplification of the EGFR gene, which is localized on band 7p13. These findings corroborate previous reports on coamplification of sequences on different chromosomes in glioblastoma.