title: A de novo interstitial deletion of chromosome 15 band q25 as revealed by FISH-technique.
abstract: We report a new chromosomal finding in a 20 month-old girl. The minor clinical features included: moderate mental retardation, microcephaly, mild hypotonia and hypertelorism. Initially, what appeared to be a terminal deletion of the long arm of one chromosome 15 [15q26-->qter] was determined to be an interstitial deletion involving band 15q25 as revealed by FISH-technique, showing the presence of intact telomeric hybridization signals. The cytogenetic diagnosis was thus modified to 46,XX, del (15) (pter-->q24::q26--> qter). Nevertheless, the function of the enzyme telomerase should not be ignored, as healing could occur following such terminal deletions. Consequently, it will remain a difficult task to distinguish terminal deletions from those that are interstitial.
authors.affiliation: Division of Genetics, Stanley S. Lamm Institute for Child Neurology and Developmental Medicine, Long island College Hospital-SUNY Health Science Center at Brooklyn, NY 11201, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Verma
authors.forename: S M
authors.initials: SM
authors.lastname: Kleyman
authors.forename: R
authors.initials: R
authors.lastname: Giridharan
authors.forename: K H
authors.initials: KH
authors.lastname: Ramesh
mesh_terms: D002871:Chromosome Banding; D002872:Chromosome Deletion; D002884:Chromosomes, Human, Pair 15; D002658:Developmental Disabilities / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007621:Karyotyping