title: Dicentric chromosome 9 due to tandem duplication of the 9p11-q13 region: unusual chromosome 9 variant.
abstract: We report on a 31-year-old mentally retarded woman with minor facial anomalies and a heteromorphic chromosome 9 with tandem duplication of the 9p11-q13 pericentromeric region. To the best of our knowledge, this is the first report of tandem duplication of this region. An identical chromosome 9 morphology was found in the healthy and phenotypically normal sister of the proposita. The usefulness of double-color FISH techniques and the presumed mechanism accounting for the origin of the chromosomal anomaly and for the phenotypic discordance observed between the two sisters are discussed.
authors.affiliation: Center for Human Genetics, University of Leuven, Belgium.
authors.forename: T
authors.initials: T
authors.lastname: Lukusa
authors.forename: K
authors.initials: K
authors.lastname: Devriendt
authors.forename: M
authors.initials: M
authors.lastname: Holvoet
authors.forename: J P
authors.initials: JP
authors.lastname: Fryns
mesh_terms: D000328:Adult; D002503:Centromere / Q000473:pathology*; D002869:Chromosome Aberrations / Q000235:genetics*; D002871:Chromosome Banding; D025063:Chromosome Disorders; D002899:Chromosomes, Human, Pair 9; D019465:Craniofacial Abnormalities / Q000150:complications / Q000235:genetics; D004461:Eclampsia / Q000473:pathology; D005260:Female; D020440:Gene Duplication; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008607:Intellectual Disability / Q000150:complications / Q000235:genetics; D009679:Nuclear Family; D011247:Pregnancy