Format

Send to

Choose Destination
PLoS One. 2015 Apr 10;10(4):e0123886. doi: 10.1371/journal.pone.0123886. eCollection 2015.

Genetic basis of a cognitive complexity metric.

Author information

1
Neuroimaging Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
2
School of Applied Psychology, Griffith University, Mt Gravatt Campus, Brisbane, Australia; Behavioural Basis of Health Program, Griffith Health Institute and School of Applied Psychology, Griffith University, Brisbane, Australia.
3
School of Applied Psychology, Griffith University, Gold Coast Campus, Southport, Australia; Behavioural Basis of Health Program, Griffith Health Institute and School of Applied Psychology, Griffith University, Brisbane, Australia.
4
Behavioural Basis of Health Program, Griffith Health Institute and School of Applied Psychology, Griffith University, Brisbane, Australia.
5
Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, United Kingdom; Centre for Genomic and Experimental Medicine, University of Edinburgh, Edinburgh, United Kingdom.
6
Centre for Genomic and Experimental Medicine, University of Edinburgh, Edinburgh, United Kingdom; Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom.
7
Department of Biological Psychology, Vrije Universiteit, Amsterdam, The Netherlands.
8
K.G. Jebsen Centre for Psychosis Research and the Norwegian Center for Mental Disorders Research (NORMENT), Department of Clinical Science, University of Bergen, Bergen, Norway; Dr Einar Martens Research Group for Biological Psychiatry, Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway.
9
Genetic Epidemiology, QIMR Berghofer Medical Research Institute, Brisbane, Australia; School of Psychology, University of Queensland, St Lucia, Brisbane, Australia.
10
Molecular Genetic Epidemiology, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
11
Quantitative Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
12
Avera Institute for Human Genetics, Avera McKennan Hospital & University Health Center, Sioux Falls, South Dakota, United States of America.
13
K.G. Jebsen Center for Research on Neuropsychiatric Disorders, University of Bergen, Bergen, Norway; Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway; Center for Research on Aging and Dementia, Haraldsplass Deaconess Hospital, Bergen, Norway.
14
Department of Psychology, University of Oslo, Oslo, Norway.
15
Molecular Epidemiology, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
16
Department of Psychology, University of Oslo, Oslo, Norway; Norwegian Center for Mental Disorders Research (NORMENT) and the K.G. Jebsen Center for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
17
Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands.
18
Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom; Alzheimer Scotland Dementia Research Centre, University of Edinburgh, Edinburgh, United Kingdom.
19
Genetic Epidemiology, QIMR Berghofer Medical Research Institute, Brisbane, Australia.

Abstract

Relational complexity (RC) is a metric reflecting capacity limitation in relational processing. It plays a crucial role in higher cognitive processes and is an endophenotype for several disorders. However, the genetic underpinnings of complex relational processing have not been investigated. Using the classical twin model, we estimated the heritability of RC and genetic overlap with intelligence (IQ), reasoning, and working memory in a twin and sibling sample aged 15-29 years (N = 787). Further, in an exploratory search for genetic loci contributing to RC, we examined associated genetic markers and genes in our Discovery sample and selected loci for replication in four independent samples (ALSPAC, LBC1936, NTR, NCNG), followed by meta-analysis (N>6500) at the single marker level. Twin modelling showed RC is highly heritable (67%), has considerable genetic overlap with IQ (59%), and is a major component of genetic covariation between reasoning and working memory (72%). At the molecular level, we found preliminary support for four single-marker loci (one in the gene DGKB), and at a gene-based level for the NPS gene, having influence on cognition. These results indicate that genetic sources influencing relational processing are a key component of the genetic architecture of broader cognitive abilities. Further, they suggest a genetic cascade, whereby genetic factors influencing capacity limitation in relational processing have a flow-on effect to more complex cognitive traits, including reasoning and working memory, and ultimately, IQ.

PMID:
25860228
PMCID:
PMC4393228
DOI:
10.1371/journal.pone.0123886
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center