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Cited by 460Schizophrenia research and treatmentBipolar Disorder and TreatmentGenetic Associations and Epidemiology

A Twin Study of Genetic Relationships Between Psychotic Symptoms

Cardno, Alastair G., Rijsdijk, Frühling V., Sham, Pak C., Murray, Robin M., McGuffin, Peter·2002·American Journal of Psychiatry
DOI 10.1176/appi.ajp.159.4.539
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Abstract

OBJECTIVE: Biometrical model fitting was applied to clinical data from twins to investigate whether operationally defined schizophrenic, schizoaffective, and manic syndromes share genetic risk factors. METHOD: Seventy-seven monozygotic and 89 same-sex dizygotic twin pairs in which the proband met the Research Diagnostic Criteria (RDC) for lifetime-ever schizophrenic, schizoaffective, or manic syndrome were ascertained from the Maudsley Twin Register in London. The syndromes were defined non-hierarchically. Correlations in liability were calculated for each syndrome in the monozygotic and dizygotic pairs and across the three pairings of schizophrenic-manic, schizophrenic-schizoaffective, and schizoaffective-manic syndromes both within probands and within pairs. For the three syndromes considered together, an independent pathway model was fitted. RESULTS: The model fitting showed significant genetic correlations between all three syndromes. There was evidence of both common and syndrome-specific genetic contributions to the variance in liability to the schizophrenic and manic syndromes, but the genetic liability to the schizoaffective syndrome was entirely shared in common with the other two syndromes. In contrast, environmental liability to the schizoaffective syndrome was not shared with the other syndromes. CONCLUSIONS: If diagnostic hierarchies are relaxed, there is a degree of overlap in the genes contributing to RDC schizophrenic, schizoaffective, and manic syndromes. Supplementing the traditional approach of assigning a single main lifetime diagnosis with information on within-person comorbidity of psychotic syndromes may provide valuable information about the familial aggregation of psychotic symptoms.

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  • Schizophrenia shares significant overlap with bipolar disorder, including PV-IN pathology.

    “Schizophrenia also shares significant overlap with BPD [55,56], including PV-IN pathology.”

    From Parvalbumin interneuron vulnerability and brain disorders (2021) · cites this paper as [56]

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Authors
Cardno, A. G., Rijsdijk, F. V., Sham, P. C., Murray, R. M., & McGuffin, P.
Affiliations
  • Cardiff University (GB)
  • King's College London (GB)
ORCID
Venue
American Journal of Psychiatry
Publisher
American Psychiatric Association Publishing
Published
2002-04
Volume
159
Issue
4
Pages
539-545
ISSN
  • 0002-953X (ISSN-L)
  • 1535-7228
DOI
10.1176/appi.ajp.159.4.539
OpenAlex
W2019813370
Cited by
460
References
18
Citations by year
2026: 5 · 2025: 1 · 2023: 3 · 2022: 7 · 2021: 12 · 2020: 7 · 2019: 21 · 2018: 10 · 2017: 16 · 2016: 13 · 2015: 7 · 2014: 23 · 2013: 21 · 2012: 24
FWCI
16.06
Type
journal article
Language
en
Open access
closed
Locations
  • American Journal of Psychiatry (publishedVersion)
  • PubMed (publishedVersion)
  • The HKU Scholars Hub (University of Hong Kong) (submittedVersion)
  • Research Portal (King's College London) (submittedVersion)
  • DigitalGeorgetown (Georgetown University Library) (submittedVersion)
Funders
National Institute of Mental Health (MH-44359, R01MH044359)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
  • Health Sciences › Medicine › Psychiatry and Mental health › Bipolar Disorder and Treatment
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic Associations and Epidemiology
Keywords
genetic susceptibility, psychosis, schizophrenia, schizoaffective disorder, manic syndrome, genetic correlation, monozygotic twins, dizygotic twins, comorbidities, familial aggregation, environmental liability
MeSH terms
Adolescent, Adult, Aged, Aged, 80 and over, Bipolar Disorder, Diseases in Twins, Female, Humans, London, Male, Middle Aged, Models, Genetic, Psychotic Disorders, Registries, Schizophrenia, Schizophrenic Psychology, Social Environment, Twins, Dizygotic, Twins, Monozygotic, Risk Assessment, Genetic Predisposition to Disease

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