title: Interstitial deletion of chromosome 9q with coexistence of the deleted segment as a ring chromosome. A case report.
abstract: In a mentally retarded female an interstitial deletion of a chromosome 9 and an additional ring chromosome was shown, which by positive hybridisation with a no 9 library was considered to be the excised segment. The functional centromere and C and DA/DAPI positive material as well on the ring chromosome are explained by a break within the centromere close to the constitutive heterochromatin and supports the hypothesis of "latent" centromere(s).
authors.affiliation: Institut für Humangenetik, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany.
authors.forename: R A
authors.initials: RA
authors.lastname: Pfeiffer
authors.forename: U
authors.initials: U
authors.lastname: Trautmann
authors.forename: R
authors.initials: R
authors.lastname: Hirmer-Stoll
mesh_terms: D002872:Chromosome Deletion; D002899:Chromosomes, Human, Pair 9; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007621:Karyotyping; D012303:Ring Chromosomes