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Imprinting in Prader–Willi and Angelman syndromes

Part 1. Genetics

1.3. Epigenetics

Specialist Review

  1. Bernhard Horsthemke,
  2. Karin Buiting

Published Online: 15 NOV 2005

DOI: 10.1002/047001153X.g103214

Encyclopedia of Genetics, Genomics, Proteomics and Bioinformatics

Encyclopedia of Genetics, Genomics, Proteomics and Bioinformatics

How to Cite

Horsthemke, B. and Buiting, K. 2005. Imprinting in Prader–Willi and Angelman syndromes. Encyclopedia of Genetics, Genomics, Proteomics and Bioinformatics. 1:1.3:29.

Author Information

  1. Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany

Publication History

  1. Published Online: 15 NOV 2005

Abstract

The Prader–Willi syndrome (PWS) and Angelman syndrome (AS) are two distinct neurogenetic diseases that are caused by the loss of function of imprinted genes on the proximal long arm of human chromosome 15. The identification of small deletions in a subgroup of patients in whom the loss of gene function is due to an incorrect imprint on the paternal or the maternal chromosome 15, respectively, has lead to the definition of a bipartite imprinting center that regulates in cis imprint resetting and imprint maintenance in the whole domain. These findings have been confirmed and extended in knockout and transgenic mice. In the majority of patients with an imprinting defect, the incorrect imprint has arisen without a DNA sequence change, probably as the result of stochastic errors of the imprinting process. It is possible that the error rate is affected by genetic and exogenous factors.

Keywords:

  • Prader–Willi syndrome;
  • Angelman syndrome;
  • imprinting;
  • DNA methylation