Brief Communications

Nature 403, 501-502 (3 February 2000) | doi:10.1038/35000656

Embryogenesis: Demethylation of the zygotic paternal genome

Wolfgang Mayer1,3, Alain Niveleau2, Jörn Walter1, Reinald Fundele1 & Thomas Haaf1

In mammals, both parental genomes undergo dramatic epigenetic changes after fertilization to form the diploid somatic genome. Here we show that the paternal genome in the mouse is significantly and actively demethylated within 6–8 hours of fertilization, before the onset of DNA replication, whereas the maternal genome is demethylated after several cleavage divisions. This active demethylation of the paternal genome may be associated with epigenetic remodelling of sperm chroma-tin, in order to establish parent-specific developmental programmes during early embryogenesis.

  1. Max Planck Institute of Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
  2. Molecular and Structural Virology Unit, Université J. Fourier de Grenoble, 38706 La Tronche, France
  3. Deceased.

Correspondence to: Thomas Haaf1 e-mail: Email: