Two-step imprinted X inactivation: repeat versus genic silencing in the mouse

Satoshi H Namekawa1, Bernhard Payer, Khanh D Huynh

  • 1Howard Hughes Medical Institute, Department of Molecular Biology, Massachusetts General Hospital, Department of Genetics, Harvard Medical School, Boston, MA, USA.

Summary

Mammals use X chromosome inactivation (XCI) to balance gene dosage. Paternal X chromosome (X(P)) inactivation in early embryos occurs in two steps: repeat silencing then gene silencing, with Xist RNA acting late.

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