title: A new patient with pure trisomy 4p resulting from isochromosome formation and whole arm translocation.
abstract: Short arm isochromosome formation with translocation of the entire long arm of the same chromosome is an unusual constitutional abnormality that has been observed, to our knowledge, in 18 cases. Only one of these previously reported cases involved chromosome 4, resulting in pure trisomy 4p. Pure trisomy 4p has been reported in a number of cases, the majority of them due to familial chromosome rearrangements, and is associated with a distinct pattern of abnormal findings. We report here a second case of a de novo chromosome 4 whole arm translocation with short-arm isochromosome formation, which we have delineated further by FISH studies.
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, PO Box 11-236, Beirut, Lebanon. lailaz@aub.edu.lb
authors.forename: L
authors.initials: L
authors.lastname: Zahed
authors.forename: G
authors.initials: G
authors.lastname: Oreibi
authors.forename: H
authors.initials: H
authors.lastname: El-Amine
authors.forename: M
authors.initials: M
authors.lastname: Obeid
authors.forename: F F
authors.initials: FF
authors.lastname: Bitar
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics; D002545:Brain Ischemia / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007231:Infant, Newborn; D018404:Isochromosomes / Q000235:genetics*; D007621:Karyotyping; D014314:Trisomy