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Cloning of the SCA7 gene reveals a highly unstable CAG repeat expansion

Nature Genetics volume 17, pages 65–70 (1997)Cite this article

Abstract

The gene for spinocerebellar ataxia 7 (SCA7) has been mapped to chromosome 3p12–13. By positional cloning, we have identified a new gene of unknown function containing a CAG repeat that is expanded in SCA7 patients. On mutated alleles, CAG repeat size is highly variable, ranging from 38 to 130 repeats, whereas on normal alleles it ranges from 7 to 17 repeats. Gonadal instability in SCA7 is greater than that observed in any of the seven known neuro-degenerative diseases caused by translated CAG repeat expansions, and is markedly associated with paternal transmissions. SCA7 is the first such disorder in which the degenerative process also affects the retina.

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Author information

Author notes

  1. Gilles David and Nacer Abbas: G.D. & N.A. contributed equally to this work.

Authors and Affiliations

  1. INSERM U289, Hôpital de la Salpêtrière, 47 bd. de I'Hôpital, 75651, Paris, Cedex 13, France

    Gilles David, Nacer Abbas, Giovanni Stevanin, Alexandra Dürr, Géraldine Cancel, Merle Ruberg, Yves Agid & Alexis Brice

  2. Fédération de Neurologie, Hôpital de la Salpêtrière, 47 bd. de l'Hôpital, 75651, Paris, Cedex 13, France

    Alexandra Dürr, Yves Agid & Alexis Brice

  3. Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS, INSERM, ULP, B.P. 163, 67404, Illkirch Cedex, C U. de Strasbourg, France

    Gaël Yvert, Chantal Weber, Georges Imbert, Frédéric Saudou & Jean-Louis Mandel

  4. University of Colorado Health Sciences Center, 4200 East 9th Avenue, Denver, Colorado, 80262, USA

    Eric Antoniou, Harry Drabkin & Robert Gemmill

  5. Institute of Neurology, Queen Square, London, WC1N3BG, UK

    Paola Giunti & Nick Wood

  6. Service de Neurologie (Prof. T. Chkili), Hôpital des Speéialtiés, Rabat, Morocco

    Ali Benomar

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  1. Gilles David
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  2. Nacer Abbas
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Corresponding author

Correspondence to Ali Benomar.

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David, G., Abbas, N., Stevanin, G. et al. Cloning of the SCA7 gene reveals a highly unstable CAG repeat expansion. Nat Genet 17, 65–70 (1997). https://doi.org/10.1038/ng0997-65

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