title: CDKN2 (p16/MTS1) gene deletion or CDK4 amplification occurs in the majority of glioblastomas.
abstract: Forty-six glioblastomas, 16 anaplastic astrocytomas, and 8 astrocytomas were studied for the loss of the CDKN2 (p16/MTS1) gene on 9p. The CDKN2 locus was homozygously deleted in 19 of 46 glioblastomas (41%) and 1 allele was lost in an additional 13 cases (28%). The deleted regions were limited centromerically in some cases by the MTS2 locus and telomerically by the 1063.7 locus. CDKN2 was homozygously deleted in 3 of 16 anaplastic astrocytomas (19%) and 2 further cases showed loss of 1 allele. Amplification of the CDK4 gene was present in 7 of 14 (50%) glioblastomas and 3 of 11 (27%) anaplastic astrocytomas with no losses at the CDKN2 locus as well as in 2 of 32 (6%) glioblastomas with CDKN2 losses. Thus one or more of these two genes were shown to be aberrant in 85% of glioblastomas and 50% of anaplastic astrocytomas. None of the 8 astrocytomas showed abnormalities of these genes.
authors.affiliation: Institute for Oncology and Pathology, Karolinska Hospital, Stockholm, Sweden.
authors.forename: E E
authors.initials: EE
authors.lastname: Schmidt
authors.forename: K
authors.initials: K
authors.lastname: Ichimura
authors.forename: G
authors.initials: G
authors.lastname: Reifenberger
authors.forename: V P
authors.initials: VP
authors.lastname: Collins
mesh_terms: D000483:Alleles; D001254:Astrocytoma / Q000235:genetics; D001483:Base Sequence; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D005784:Gene Amplification / Q000235:genetics*; D017353:Gene Deletion; D005909:Glioblastoma / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data