title: High-resolution array-CGH profiling of germline and tumor-specific copy number alterations on chromosome 22 in patients affected with schwannomas.
abstract: Schwannomas may develop sporadically or in association with NF2 and schwannomatosis. The fundamental aberration in schwannomas is the bi-allelic inactivation of the NF2 gene. However, clinical and molecular data suggest that these tumors share a common pathogenetic mechanism related to as yet undefined 22q-loci. Linkage studies in schwannomatosis, a condition related to NF2, have defined a candidate 22q-locus and excluded the NF2 gene as the causative germline mutation. Thus, analysis of aberrations in schwannomas may lead to the identification of putative gene(s) involved in the development of schwannoma/schwannomatosis. We profiled a series of 88 schwannomas and constitutional DNA using a tiling path chromosome 22 array. Array-CGH is a suitable method for high-resolution discrimination between germline and tumor-specific aberrations. Previously reported frequencies of 22q-associated deletions in schwannomas display large discrepancies, ranging from 30% to 80%. We detected heterozygous deletions in 53% of schwannomas and the predominant pattern was monosomy 22. In addition, three tumors displayed terminal deletions and four harbored overlapping interstitial deletions of various sizes encompassing the NF2 gene. When profiling constitutional DNA, we identified eight loci that were affected by copy number variation (CNV). Some of the identified CNVs may not be phenotypically neutral and the possible role of these CNVs in the pathogenesis of schwannomas should be studied further. We observed a correlation between the breakpoint position, present in tumor and/or constitutional DNA and the location of segmental duplications. This association implicates these unstable regions in rearrangements occurring both in meiosis and mitosis.
authors.affiliation: Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, 751 85, Uppsala, Sweden.
authors.forename: Teresita
authors.initials: T
authors.lastname: Díaz de Ståhl
authors.forename: Caisa M
authors.initials: CM
authors.lastname: Hansson
authors.forename: Cecilia
authors.initials: C
authors.lastname: de Bustos
authors.forename: Kiran K
authors.initials: KK
authors.lastname: Mantripragada
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Piotrowski
authors.forename: Magdalena
authors.initials: M
authors.lastname: Benetkiewicz
authors.forename: Caroline
authors.initials: C
authors.lastname: Jarbo
authors.forename: Leif
authors.initials: L
authors.lastname: Wiklund
authors.forename: Tiit
authors.initials: T
authors.lastname: Mathiesen
authors.forename: Gunnar
authors.initials: G
authors.lastname: Nyberg
authors.forename: V Peter
authors.initials: VP
authors.lastname: Collins
authors.forename: D Gareth
authors.initials: DG
authors.lastname: Evans
authors.forename: Koichi
authors.initials: K
authors.lastname: Ichimura
authors.forename: Jan P
authors.initials: JP
authors.lastname: Dumanski
mesh_terms: D002892:Chromosomes, Human, Pair 22; D005260:Female; D016515:Genes, Neurofibromatosis 2; D005854:Germ Cells; D006801:Humans; D008297:Male; D009442:Neurilemmoma / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis