title: Subtelomeric study of 132 patients with mental retardation reveals 9 chromosomal anomalies and contributes to the delineation of submicroscopic deletions of 1pter, 2qter, 4pter, 5qter and 9qter.
abstract: BACKGROUND
  Cryptic chromosome imbalances are increasingly acknowledged as a cause for mental retardation and learning disability. New phenotypes associated with specific rearrangements are also being recognized. Techniques for screening for subtelomeric rearrangements are commercially available, allowing the implementation in a diagnostic service laboratory. We report the diagnostic yield in a series of 132 subjects with mental retardation, and the associated clinical phenotypes.
  
  
  METHODS
  We applied commercially available subtelomeric fluorescence in situ hybridization (FISH). All patients referred for subtelomeric screening in a 5-year period were reviewed and abnormal cases were further characterized clinically and if possible molecularly.
  
  
  RESULTS
  We identified nine chromosomal rearrangements (two of which were in sisters) corresponding to a diagnostic yield of approx. 7%. All had dysmorphic features. Five had imbalances leading to recognizable phenotypes.
  
  
  CONCLUSIONS
  Subtelomeric screening is a useful adjunct to conventional cytogenetic analyses, and should be considered in mentally retarded subjects with dysmorphic features and unknown cause.
authors.affiliation: The John F, Kennedy Institute, Glostrup, Denmark. msg@cancer.dk
authors.forename: Marie
authors.initials: M
authors.lastname: Sogaard
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Tümer
authors.forename: Helle
authors.initials: H
authors.lastname: Hjalgrim
authors.forename: Johanne
authors.initials: J
authors.lastname: Hahnemann
authors.forename: Birgitte
authors.initials: B
authors.lastname: Friis
authors.forename: Paal
authors.initials: P
authors.lastname: Ledaal
authors.forename: Vibeke Faurholt
authors.initials: VF
authors.lastname: Pedersen
authors.forename: Peter
authors.initials: P
authors.lastname: Baekgaard
authors.forename: Niels
authors.initials: N
authors.lastname: Tommerup
authors.forename: Sultan
authors.initials: S
authors.lastname: Cingöz
authors.forename: Morten
authors.initials: M
authors.lastname: Duno
authors.forename: Karen
authors.initials: K
authors.lastname: Brondum-Nielsen
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics; D000293:Adolescent; D000328:Adult; D001848:Bone Diseases, Developmental / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D020223:Chromosome Painting / Q000379:methods; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics; D019465:Craniofacial Abnormalities / Q000235:genetics; D005260:Female; D006130:Growth Disorders / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D013577:Syndrome; D016615:Telomere / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics