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Down Syndrome

  1. Angela J Villar,
  2. Charles J Epstein

Published Online: 27 JAN 2006

DOI: 10.1038/npg.els.0005711



How to Cite

Villar, A. J. and Epstein, C. J. 2006. Down Syndrome. eLS. .

Author Information

  1. University of California, San Francisco, California, USA

Publication History

  1. Published Online: 27 JAN 2006

This is not the most recent version of the article. View current version (17 OCT 2011)


Down syndrome, first described by Langdon Down in 1866, is caused by an extra copy of chromosome 21. It is the most commonly recognized genetic cause of mental retardation and is characterized by a number of dysmorphic features and congenital malformations.


  • mental retardation;
  • chromosome 21;
  • trisomy;
  • aneuploidy;
  • Alzheimer disease;
  • congenital heart disease;
  • mouse models