Article Text

Download PDFPDF
Partial trisomy of chromosome 22 resulting from an interstitial duplication of 22q11.2 in a child with typical cat eye syndrome
  1. M Meins1,
  2. P Burfeind1,
  3. S Motsch2,
  4. R Trappe1,
  5. D Bartmus3,
  6. S Langer4,
  7. M R Speicher4,
  8. H Mühlendyck2,
  9. I Bartels1,
  10. B Zoll1
  1. 1Institute of Human Genetics, University of Göttingen, Germany
  2. 2Eye Clinic, University of Göttingen, Germany
  3. 3Paediatric Cardiology, University of Göttingen, Germany
  4. 4Institute of Human Genetics, Technical University München and GSF, Neuherberg, Germany
  1. Correspondence to:
 Dr B Zoll, Institute of Human Genetics, University of Goettingen, Heinrich-Dueker-Weg 12, D-37073 Goettingen, Germany; 

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Cat eye syndrome (CES) is a rare malformation syndrome with a variable pattern of congenital anomalies. The characteristic features of CES include ocular coloboma, preauricular pits or tags, anal anomalies, and congenital heart and renal malformations. Furthermore, CES may be associated with other craniofacial malformations, skeletal anomalies, and, in some cases, with mental retardation.1,2 In almost all cases CES is associated with the cytogenetic finding of a supernumerary marker chromosome consisting of duplicated material of chromosome 22. The marker is usually bisatellite and dicentric (idic(22)(pter→q11.2::q11.2→pter)) and thus results in tetrasomy of the p arm and a part of 22q11.2.1,3

Cytogenetically detectable intrachromosomal direct or inverted duplications are rare and can arise with equal frequency by rearrangement between sister chromatids or non-sister chromatids both on the maternal or paternal chromosome.4 The proximal part of the long arm of chromosome 22 (22q11.2) has been recognised as a hot spot for chromosomal rearrangements and contains both the cat eye and the DiGeorge critical region (for reviews see Kotzot et al5 and Edelmann et al6). Multiple congenital malformations showing overlap with CES can arise from familial translocation t(11;22) in the der(22) syndrome,7,8 and, in rare cases, from interstitial duplication of proximal 22q.9–11 However, none of these patients described so far with interstitial duplications of 22q showed the full CES phenotype including all major clinical features. We report here a patient with an interstitial inverted duplication of 22q11.2 and typical features of cat eye syndrome including coloboma, preauricular anomalies, heart defect, renal anomalies, and anal atresia.

Key points

  • Cat eye syndrome (CES) is a rare malformation syndrome with characteristic major features.

  • CES is usually associated with a supernumerary bisatellited marker chromosome containing material of chromosome 22 (idic(22)(pter→q11.2::q11.2→pter)), which results in partial tetrasomy 22.

  • We …

View Full Text