- A dictionary of medical eponyms

Mary Frances Lyon

Born  1925

Related eponyms

British cytogeneticist, born 1925, Norwich.

Biography of Mary Frances Lyon

Mary Frances Lyon graduated B.A. from Cambridge University in 1946 and obtained her ScD from the same university in 1948. She then joined a group in Edinburgh set up to study the genetic hazards of radiation, using mutagenesis experiments in mice. In 1955 she moved with this group to the MRC Radiobiology Unit, Harwell, where she headed the Genetics Section from 1962-86. It was while working on radiation hazards in 1961 that she discovered X-chromosome inactivation, for which she is best known. Her research has allowed us to understand the genetic control mechanisms of chromosome X, which explains the absence of symptoms in numerous healthy women that are carriers of diseases associated with this chromosome. An example is Duchenne’s muscular dystrophy (entered on whonamedit.com as Duchenne-Griesinger). She has also done extensive work on the mouse t-complex, and made many other contributions to mammalian genetics.

Mary Frances Lyon is a Fellow of the Royal Society, a Foreign Associate of the US National Academy of Sciences, and a Foreign Honorary Member of the American Academy of Arts and Sciences. In 1994 she won the Mauro Baschirotto Award in Human Genetics, in 1997 the Wolf Prize for Medicine, for her hypothesis concerning the random inactivation of X-chromosomes in mammals. In 1997 she also received the Amory Prize, for genetic discoveries relating to mammalian sex chromosomes. Mary Frances Lyon is head of Genetics Section, Medical Research Council Radiobiology Unit, Harwell, England.


  • Mary Frances Lyon:
    Dr Charles Edmund Ford, FRS.
    Biographical Memoirs of Fellows of the Royal Society, Volume 47, 2001.
  • Judith A. Dilts:
    Mary Frances Lyon (1925- ).
    In: Louise S. Grinstein, Carol A. Biermann, and Rose K. Rose, editors:
    Women in the Biological Sciences. A Biobibliographic Sourcebook.

    Greenwood Press. Westport, Connecticut. 1997. 640 pages.

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An eponym is a word derived from the name of a person, whether real or fictional. A medical eponym is thus any word related to medicine, whose name is derived from a person.

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