Evolution of Mammalian X-chromosome Inactivation: Sex Chromatin in Monotremes and Marsupials Academic Article uri icon


  • The inactive mammalian X-chromosome is always late-replicating, and in eutherian mammals it is heterochromatic and hypermethylated. We propose that this multistep system has evolved from a more primitive system, remnants of which may be found in marsupials and monotremes.


  • Graves, Jenny
  • M McKay, Lynette
  • M Wrigley, Jaclyn
  • A MarshalI Graves, Jennifer

publication date

  • 1987