J Med Genet 44:562-569 doi:10.1136/jmg.2007.049510
  • Original article

The C20orf133 gene is disrupted in a patient with Kabuki syndrome

Open Access
  1. Nicole M C Maas1,
  2. Tom Van de Putte2,
  3. Cindy Melotte1,
  4. Annick Francis2,
  5. Constance T R M Schrander-Stumpel3,
  6. Damien Sanlaville4,
  7. David Genevieve4,
  8. Stanislas Lyonnet4,
  9. Boyan Dimitrov1,
  10. Koenraad Devriendt1,
  11. Jean-Pierre Fryns1,
  12. Joris R Vermeesch1
  1. 1Centre for Human Genetics, University of Leuven, Leuven, Belgium
  2. 2Laboratory of Molecular Biology (Celgen), Division Molecular and Developmental Genetics, Department of Human Genetics, KU Leuven and Department of Molecular and Developmental Genetics (VIB11), Leuven, Belgium
  3. 3Department of Clinical Genetics, Academic hospital Maastricht and Research Institute GROW, Maastricht University, Maastricht, The Netherlands
  4. 4Department of Genetics, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
  1. Correspondence to:
 J R Vermeesch
 Center for Human Genetics, Herestraat 49, 3000 Leuven, Belgium; joris.vermeesch{at}
  • Received 1 February 2007
  • Accepted 22 May 2007
  • Revised 15 May 2007
  • Published Online First 23 June 2007


Background: Kabuki syndrome (KS) is a rare, clinically recognisable, congenital mental retardation syndrome. The aetiology of KS remains unknown.

Methods: Four carefully selected patients with KS were screened for chromosomal imbalances using array comparative genomic hybridisation at 1 Mb resolution.

Results: In one patient, a 250 kb de novo microdeletion at 20p12.1 was detected, deleting exon 5 of C20orf133. The function of this gene is unknown. In situ hybridisation with the mouse orthologue of C20orf133 showed expression mainly in brain, but also in kidney, eye, inner ear, ganglia of the peripheral nervous system and lung.

Conclusion: The de novo nature of the deletion, the expression data and the fact that C20orf133 carries a macro domain, suggesting a role for the gene in chromatin biology, make the gene a likely candidate to cause the phenotype in this patient with KS. Both the finding of different of chromosomal rearrangements in patients with KS features and the absence of C20orf133 mutations in 19 additional patients with KS suggest that KS is genetically heterogeneous.


  • Published Online First 22 June 2007

  • Competing interests: None declared.