- A dictionary of medical eponyms

Lyon's hypothesis

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Hypothesis stating that only one of the two X-chromosomes is genetically active in female cells. X inactivation occurs around the 16th day of embryonic development.


  • M. F. Lyon:
    Gene action in the X-chromosome of the mouse (Mus musculus).
    Nature, London, 1961, 190: 372-373.
    Theory of differential inactivation of the X-chromosome.

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