Substantial genetic link between iq and working memory: Implications for molecular genetic studies on schizophrenia. the european twin study of schizophrenia (EUTwinsS)

Authors

  • Ximena Goldberg,

    Corresponding author
    1. Unitat d'Antropologia, Departament de Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
    • Unitat Antropologia, Departament Biologia AnimalFacultat de Biologia, Universitat de Barcelona, Av. Diagonal, 643, Edifici Margalef, 2ª planta, 08028, Barcelona, Spain.
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  • Silvia Alemany,

    1. Unitat d'Antropologia, Departament de Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
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  • Araceli Rosa,

    1. Unitat d'Antropologia, Departament de Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
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  • Marco Picchioni,

    1. Department of Psychosis Studies, Institute of Psychiatry, Kinǵs College London, London, UK
    2. St Andrew's Academic Centre, Northampton, UK
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  • Igor Nenadic,

    1. Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany
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  • Sheena F. Owens,

    1. Department of Psychosis Studies, Institute of Psychiatry, Kinǵs College London, London, UK
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  • Fruhling Rijsdijk,

    1. Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, UK
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  • Irene Rebollo,

    1. Department of Psychosis Studies, Institute of Psychiatry, Kinǵs College London, London, UK
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  • Heinrich Sauer,

    1. Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany
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  • Robin M. Murray,

    1. Department of Psychosis Studies, Institute of Psychiatry, Kinǵs College London, London, UK
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  • Lourdes Fañanás,

    1. Unitat d'Antropologia, Departament de Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
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  • Timothea Toulopoulou

    1. Department of Psychosis Studies, Institute of Psychiatry, Kinǵs College London, London, UK
    2. Department of Psychology, The University of Hong Kong, Hong Kong, China
    3. State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, SAR, China
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  • How to cite this article: Goldberg X, Alemany S, Rosa A, Picchioni M, Nenadic I, Owens SF, Rijsdijk F, Rebollo I, Sauer H, Murray RM, Fañanás L, Toulopoulou T. 2013. Substantial Genetic Link Between Iq and Working Memory: Implications for Molecular Genetic Studies on Schizophrenia. The European Twin Study of Schizophrenia (EUTwinsS). Am J Med Genet Part B 162B:413–418.

  • The authors have no conflict of interest to declare.

Abstract

While evidence is accumulating to support specific neurocognitive deficits as putative endophenotypes for schizophrenia, the heritability of these deficits in healthy subjects and whether they share common genetic influences, is not well established. In the present study, 529 healthy adult twins from two centers within the European Twin Study Network on Schizophrenia (EUTwinsS) were assessed on two domains that are consistently found to be particularly compromised in schizophrenia. Specifically, Intellectual Quotient Score (IQ) and the Letter–Number Sequencing Test (LNS), a measure of working memory, were measured in all twins. Latent variable components were explored through structural equation modeling, and common genetic underpinnings were examined using bivariate analyses. Results showed that the phenotypic correlation between IQ and working memory was almost entirely attributed to shared genetic variance (95.5%). We discuss the potential use of a combined measure of IQ and working memory to improve the power of molecular studies in detecting the genetic mechanisms underlying schizophrenia. © 2013 Wiley Periodicals, Inc. © 2013 Wiley Periodicals, Inc.

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