title: Pentasomy 49,XXXXY associated with a Chiari type 1 malformation and cervical syrinx.
abstract: Pentasomy 49,XXXXY occurs in 1/85,000 newborn males. The origin of this particular form of aneuploidy is believed to be a result of consecutive nondisjunction events during maternal meiosis. Typical presentation consists of hypotonia, developmental delay, various dysmorphic features, and severe hypogenitalism. A 13-year-old with pentasomy 49,XXXXY and a Chiari type 1 malformation with an associated cervical syrinx is presented.
authors.affiliation: University of Vermont, College of Medicine, Burlington, VT 05401, USA.
authors.forename: Ramin
authors.initials: R
authors.lastname: Raven
authors.forename: Peter M
authors.initials: PM
authors.lastname: Bingham
authors.forename: Patrick
authors.initials: P
authors.lastname: Graupman
mesh_terms: D000293:Adolescent; D000782:Aneuploidy; D001139:Arnold-Chiari Malformation / Q000235:genetics* / Q000473:pathology; D002574:Cervical Vertebrae; D041321:Chromosomes, Human, X; D006801:Humans; D008297:Male; D012729:Sex Chromosome Aberrations; D013595:Syringomyelia / Q000235:genetics* / Q000473:pathology