title: Multiple deleted regions on the long arm of chromosome 6 in astrocytic tumours.
abstract: Chromosome 6 deletions are common in human neoplasms including gliomas. In order to study the frequency and identify commonly deleted regions of chromosome 6 in astrocytomas, 159 tumours (106 glioblastomas, 39 anaplastic astrocytomas and 14 astrocytomas malignancy grade II) were analysed using 31 microsatellite markers that span the chromosome. Ninety-five per cent of cases with allelic losses had losses affecting 6q. Allelic losses were infrequent in astrocytomas malignancy grade II (14%) but more usual in anaplastic astrocytomas (38%) and glioblastomas (37%). Evidence for clonal heterogeneity in the astrocytomas and anaplastic astrocytomas was frequently observed (i.e. co-existence of subpopulations with and without chromosome 6 deletions). Clonal heterogeneity was less common in glioblastomas. Five commonly deleted regions were identified on 6q. These observations suggest that a number of tumour suppressor genes are located on 6q and that these genes may be involved in the progression of astrocytic tumours.
authors.affiliation: Department of Pathology, University of Cambridge, Addenbrooke's Hospital, UK.
authors.forename: A
authors.initials: A
authors.lastname: Miyakawa
authors.forename: K
authors.initials: K
authors.lastname: Ichimura
authors.forename: E E
authors.initials: EE
authors.lastname: Schmidt
authors.forename: S
authors.initials: S
authors.lastname: Varmeh-Ziaie
authors.forename: V P
authors.initials: VP
authors.lastname: Collins
mesh_terms: D001254:Astrocytoma / Q000235:genetics* / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D002503:Centromere; D002872:Chromosome Deletion; D002896:Chromosomes, Human, Pair 6; D004276:DNA, Satellite / Q000235:genetics; D018450:Disease Progression; D006801:Humans; D016615:Telomere
chemical_list: D004276:DNA, Satellite