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Afshari B, Shiri N, Ghoreishi FS, Valianpour M. Examination and Comparison of Cognitive and Executive Functions in Clinically Stable Schizophrenia Disorder, Bipolar Disorder, and Major Depressive Disorder. DEPRESSION RESEARCH AND TREATMENT 2020; 2020:2543541. [PMID: 33414961 PMCID: PMC7752301 DOI: 10.1155/2020/2543541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 11/29/2020] [Accepted: 12/10/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Schizophrenia (SC), bipolar disorder (BD), and major depressive disorder (MDD) are associated with various cognitive and executive dysfunctions. The aim of the present study was to evaluate and compare cognitive and executive dysfunctions in schizophrenia, bipolar disorder, and major depressive disorder. MATERIALS AND METHODS Sixty-four schizophrenia patients, 68 bipolar patients, 62 patients with major depressive disorder, and 75 healthy individuals participated in the present study. All participants were assessed with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Young Mania Rating Scale (YMRS), Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI-II), Trial Making Test (TMT), Four-Choice Reaction Time Task, Ruler Drop Method (RDM), Tower of London (TOL) task, and the Wisconsin Card Sorting Task (WCST). Data were analyzed by chi-square, Kolmogorov-Smirnov, and independent t-tests; ANOVA; and MANOVA. RESULTS In the cognitive function, the scores of SC, BD, and MDD patients were lower than those of healthy individuals. Also, the scores of MDD patients were lower than those of other patients, and the scores of BD patients were lower than those of SC patients. In the executive function, the scores of SC, BD, and MDD patients were lower than those of healthy individuals. Moreover, the scores of the MDD group were higher than those of the BD and SC groups, and the scores of the SC group were higher than those of the BD group. CONCLUSION Patients with SC, BD, and MDD have poorer cognitive and executive functions than healthy individuals, even when these patients are in a stable state. Assessment of cognitive and executive functions in SC, BD, and MDD patients can help in understanding the pathology of these disorders.
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Affiliation(s)
| | - Nasrin Shiri
- Kashan University of Medical Science, Kashan, Iran
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2
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Malykh SB, Malykh AS, Karunas AS, Enikeeva RF, Davydova YD, Khusnutdinova EK. Molecular Genetic Studies of Cognitive Ability. RUSS J GENET+ 2019. [DOI: 10.1134/s1022795419070111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Silva ARD, Puglisi ML, Pompéia S, Ploubidis GB, Swardfager W, Cogo-Moreira H. Birth weight, verbal cognition in early adolescence, and lexical and reading skills in late adolescence: a formal mediation analysis using a potential outcomes approach. J Child Psychol Psychiatry 2019; 60:773-783. [PMID: 30908645 DOI: 10.1111/jcpp.13043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/21/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND Oral and written language in late adolescence are influenced by many pre- and postnatal factors, including cognitive performance at earlier ages. We investigated whether the association between birth weight and lexical knowledge and reading comprehension in late adolescence (14-16 years) is mediated by verbal cognition during early adolescence (10-11 years). METHODS We conducted a mediation analysis via a potential outcomes approach to data from three United Kingdom (UK) prospective birth cohorts - The National Child Development Study (NCDS; year of birth (Y.B.) = 1,958; analytic sample size (A.N.) = 9,399; original sample size (O.N.) = 18,558), British Cohort Study (BCS70; Y.B. = 1,970; A.N. = 6,591; O.N. = 17,196), and Millennium Cohort Study (MCS; Y.B. = 2,000-2,001; A.N. = 3,950; O.N. = 18,552) - to evaluate the indirect effects of birth weight on lexical knowledge (BCS and MCS) and reading comprehension measures (NCDS) in adolescence. RESULTS We found an indirect effect but no statistically significant direct effects for the BCS and MCS cohorts. The proportion of the effect of birth weight on oral and written language in late adolescence mediated by early adolescence verbal cognition was 59.19% (BCS) and 8.41% (MCS) for lexical knowledge and 61.00% when the outcome was reading comprehension (NCDS). Sensitivity analyses, used to assess whether unmeasured variables could have affected our mediation estimates, showed that for reading comprehension, in NCDS, the indirect effect is robust; only unmeasured confounders highly correlated with the mediator and outcome (ρ = .68) would explain away the indirect effect. For lexical knowledge, smaller correlations with hypothetical confounders (ρ = .33 for BCS) would suffice to render the indirect effect non-significant; the indirect effect for MCS non statistical significant. CONCLUSIONS Birth weight affects oral and written language skills (lexical knowledge and reading comprehension) in late adolescence via verbal cognition in early adolescence in two cohorts born in 1958 and 1970, but not in a cohort born at the turn of the millennium. These indirect effects were stronger than the direct effects and are unlikely to be explained by unmeasured confounders when the outcome involves complex skills such as reading comprehension.
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Affiliation(s)
| | - Marina Leite Puglisi
- Department of Speech and Language Therapy, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Sabine Pompéia
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - George B Ploubidis
- Department of Social Science, Centre for Longitudinal Studies, UCL Institute of Education, University College London, London, UK
| | - Walter Swardfager
- Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, ON, Canada.,Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,KITE, Toronto Rehab-University Health Network, Toronto, ON, Canada
| | - Hugo Cogo-Moreira
- Department of Psychiatry, Universidade Federal de São Paulo, São Paulo, Brazil.,Department of Education and Psychology, Methods and Evolution Division, Freie Universität Berlin, Berlin, Germany
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Allegrini AG, Selzam S, Rimfeld K, von Stumm S, Pingault JB, Plomin R. Genomic prediction of cognitive traits in childhood and adolescence. Mol Psychiatry 2019; 24:819-827. [PMID: 30971729 PMCID: PMC6986352 DOI: 10.1038/s41380-019-0394-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 02/12/2019] [Accepted: 02/14/2019] [Indexed: 12/21/2022]
Abstract
Recent advances in genomics are producing powerful DNA predictors of complex traits, especially cognitive abilities. Here, we leveraged summary statistics from the most recent genome-wide association studies of intelligence and educational attainment, with highly genetically correlated traits, to build prediction models of general cognitive ability and educational achievement. To this end, we compared the performances of multi-trait genomic and polygenic scoring methods. In a representative UK sample of 7,026 children at ages 12 and 16, we show that we can now predict up to 11% of the variance in intelligence and 16% in educational achievement. We also show that predictive power increases from age 12 to age 16 and that genomic predictions do not differ for girls and boys. We found that multi-trait genomic methods were effective in boosting predictive power. Prediction accuracy varied across polygenic score approaches, however results were similar for different multi-trait and polygenic score methods. We discuss general caveats of multi-trait methods and polygenic score prediction, and conclude that polygenic scores for educational attainment and intelligence are currently the most powerful predictors in the behavioural sciences.
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Affiliation(s)
- A G Allegrini
- Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK.
| | - S Selzam
- Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - K Rimfeld
- Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - S von Stumm
- Department of Education, University of York, Heslington, York, UK
| | - J B Pingault
- Clinical Educational and Health Psychology, Division of Psychology and Language Sciences, University College London, London, UK
| | - R Plomin
- Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
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5
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Goriounova NA, Mansvelder HD. Genes, Cells and Brain Areas of Intelligence. Front Hum Neurosci 2019; 13:44. [PMID: 30828294 PMCID: PMC6384251 DOI: 10.3389/fnhum.2019.00044] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 01/25/2019] [Indexed: 12/18/2022] Open
Abstract
What is the neurobiological basis of human intelligence? The brains of some people seem to be more efficient than those of others. Understanding the biological foundations of these differences is of great interest to basic and applied neuroscience. Somehow, the secret must lie in the cells in our brain with which we think. However, at present, research into the neurobiology of intelligence is divided between two main strategies: brain imaging studies investigate macroscopic brain structure and function to identify brain areas involved in intelligence, while genetic associations studies aim to pinpoint genes and genetic loci associated with intelligence. Nothing is known about how properties of brain cells relate to intelligence. The emergence of transcriptomics and cellular neuroscience of intelligence might, however, provide a third strategy and bridge the gap between identified genes for intelligence and brain function and structure. Here, we discuss the latest developments in the search for the biological basis of intelligence. In particular, the recent availability of very large cohorts with hundreds of thousands of individuals have propelled exciting developments in the genetics of intelligence. Furthermore, we discuss the first studies that show that specific populations of brain cells associate with intelligence. Finally, we highlight how specific genes that have been identified generate cellular properties associated with intelligence and may ultimately explain structure and function of the brain areas involved. Thereby, the road is paved for a cellular understanding of intelligence, which will provide a conceptual scaffold for understanding how the constellation of identified genes benefit cellular functions that support intelligence.
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Affiliation(s)
- Natalia A. Goriounova
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Amsterdam, VU University Amsterdam, Amsterdam, Netherlands
| | - Huibert D. Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Amsterdam, VU University Amsterdam, Amsterdam, Netherlands
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Smajlagić D, Kvarme Jacobsen K, Myrum C, Haavik J, Johansson S, Zayats T. Moderating effect of mode of delivery on the genetics of intelligence: Explorative genome-wide analyses in ALSPAC. Brain Behav 2018; 8:e01144. [PMID: 30378284 PMCID: PMC6305932 DOI: 10.1002/brb3.1144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/27/2018] [Accepted: 09/30/2018] [Indexed: 01/27/2023] Open
Abstract
INTRODUCTION Intelligence is a core construct of individual differences in cognitive abilities and a strong predictor of important life outcomes. Within recent years, rates of cesarean section have substantially increased globally, though little is known about its effect on neurodevelopmental trajectories. Thus, we aimed to investigate the influence of delivery by cesarean section on the genetics of intelligence in children. METHODS Participants were recruited through the Avon Longitudinal Study of Parents and Children (ALSPAC). Intelligence was measured by the Wechsler Intelligence Scale for Children (WISC). Genotyping was performed using the Illumina Human Hap 550 quad genome-wide SNP genotyping platform and was followed by imputation using MACH software. Genome-wide interaction analyses were conducted using linear regression. RESULTS A total of 2,421 children and 2,141,747 SNPs were subjected to the genome-wide interaction analyses. No variant reached genome-wide significance. The strongest interaction was observed at rs17800861 in the GRIN2A gene (β = -3.43, 95% CI = -4.74 to -2.12, p = 2.98E-07). This variant is predicted to be located within active chromatin compartments in the hippocampus and may influence binding of the NF-kappaB transcription factor. CONCLUSIONS Our results may indicate that mode of delivery might have a moderating effect on genetic disposition of intelligence in children. Studies of considerable sizes (>10,000) are likely required to more robustly detect variants governing such interaction. In summary, the presented findings prompt the need for further studies aimed at increasing our understanding of effects various modes of delivery may have on health outcomes in children.
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Affiliation(s)
- Dinka Smajlagić
- Department of Clinical Science, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
- Center for Medical Genetics and Molecular MedicineHaukeland University HospitalBergenNorway
| | - Kaya Kvarme Jacobsen
- Department of Biomedicine, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
| | - Craig Myrum
- Department of Biomedicine, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
| | - Jan Haavik
- Department of Biomedicine, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
| | - Stefan Johansson
- Department of Clinical Science, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
- Center for Medical Genetics and Molecular MedicineHaukeland University HospitalBergenNorway
| | - Tetyana Zayats
- Department of Biomedicine, KG Jebsen Center for Neuropsychiatric DisordersUniversity of BergenBergenNorway
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7
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Abstract
Intelligence - the ability to learn, reason and solve problems - is at the forefront of behavioural genetic research. Intelligence is highly heritable and predicts important educational, occupational and health outcomes better than any other trait. Recent genome-wide association studies have successfully identified inherited genome sequence differences that account for 20% of the 50% heritability of intelligence. These findings open new avenues for research into the causes and consequences of intelligence using genome-wide polygenic scores that aggregate the effects of thousands of genetic variants.
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Affiliation(s)
- Robert Plomin
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London SE5 8AF, UK
| | - Sophie von Stumm
- Department of Psychological and Behavioural Science, London School of Economics and Political Science, Queens House, 55-56 Lincoln's Inn Fields, London WC2A 3LJ, UK
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8
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Sauce B, Matzel LD. The paradox of intelligence: Heritability and malleability coexist in hidden gene-environment interplay. Psychol Bull 2017; 144:26-47. [PMID: 29083200 DOI: 10.1037/bul0000131] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Intelligence can have an extremely high heritability, but also be malleable; a paradox that has been the source of continuous controversy. Here we attempt to clarify the issue, and advance a frequently overlooked solution to the paradox: Intelligence is a trait with unusual properties that create a large reservoir of hidden gene-environment (GE) networks, allowing for the contribution of high genetic and environmental influences on individual differences in IQ. GE interplay is difficult to specify with current methods, and is underestimated in standard metrics of heritability (thus inflating estimates of "genetic" effects). We describe empirical evidence for GE interplay in intelligence, with malleability existing on top of heritability. The evidence covers cognitive gains consequent to adoption/immigration, changes in IQ's heritability across life span and socioeconomic status, gains in IQ over time consequent to societal development (the Flynn effect), the slowdown of age-related cognitive decline, and the gains in intelligence from early education. The GE solution has novel implications for enduring problems, including our inability to identify intelligence-related genes (also known as IQ's "missing heritability"), and the loss of initial benefits from early intervention programs (such as "Head Start"). The GE solution can be a powerful guide to future research, and may also aid policies to overcome barriers to the development of intelligence, particularly in impoverished and underprivileged populations. (PsycINFO Database Record
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Affiliation(s)
- Bruno Sauce
- Department of Psychology, Program in Behavioral and Systems Neuroscience, Rutgers University
| | - Louis D Matzel
- Department of Psychology, Program in Behavioral and Systems Neuroscience, Rutgers University
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Rinaldi L, Karmiloff-Smith A. Intelligence as a Developing Function: A Neuroconstructivist Approach. J Intell 2017; 5:E18. [PMID: 31162409 PMCID: PMC6526422 DOI: 10.3390/jintelligence5020018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/21/2017] [Accepted: 04/27/2017] [Indexed: 11/16/2022] Open
Abstract
The concept of intelligence encompasses the mental abilities necessary to survival and advancement in any environmental context. Attempts to grasp this multifaceted concept through a relatively simple operationalization have fostered the notion that individual differences in intelligence can often be expressed by a single score. This predominant position has contributed to expect intelligence profiles to remain substantially stable over the course of ontogenetic development and, more generally, across the life-span. These tendencies, however, are biased by the still limited number of empirical reports taking a developmental perspective on intelligence. Viewing intelligence as a dynamic concept, indeed, implies the need to identify full developmental trajectories, to assess how genes, brain, cognition, and environment interact with each other. In the present paper, we describe how a neuroconstructivist approach better explains why intelligence can rise or fall over development, as a result of a fluctuating interaction between the developing system itself and the environmental factors involved at different times across ontogenesis.
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Affiliation(s)
- Luca Rinaldi
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia 27100, Italy.
- Milan Center for Neuroscience, Milano 20126, Italy.
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10
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Lin PY, Wang PW, Chen CS, Yen CF. Neurocognitive function in clinically stable individuals with long-term bipolar I disorder: Comparisons with schizophrenia patients and controls. Kaohsiung J Med Sci 2017; 33:260-265. [PMID: 28433073 DOI: 10.1016/j.kjms.2017.02.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/27/2017] [Accepted: 02/03/2017] [Indexed: 12/11/2022] Open
Abstract
This study compared the levels of the five domains of neurocognitive function-executive function, attention, memory, verbal comprehension, and perceptual organization-among clinically stable individuals with long-term bipolar I disorder, individuals with long-term schizophrenia, and a group of controls. We recruited a total of 93 clinically stable individuals with bipolar I disorder, 94 individuals with schizophrenia, and 106 controls in this study. Their neurocognitive function was measured using a series of neurocognitive function tests: the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), Line Cancellation Test, Visual Form Discrimination, Controlled Oral Word Association Test, Wisconsin Card Sorting Test, Continuous Performance Task, and Wechsler Memory Scale-Third Edition. Neurocognitive function was compared among the three groups through a multivariate analysis of variance. The results indicated that when the effect of age was controlled, clinically stable individuals with bipolar I disorder and those with schizophrenia demonstrated poor neurocognitive function on all tests except for the WAIS-III Similarity and Information and the Line Cancellation Test. The individuals with bipolar I disorder had similar levels of neurocognitive function compared with the schizophrenia group, but higher levels of neurocognitive function on the WAIS-III Comprehension, Controlled Oral Word Association Test, and Wechsler Memory Scale-Third Edition Auditory Immediate and Delayed Index and Visual Immediate and Delayed Index. The conclusions of this study suggest that compared with controls, individuals with long-term bipolar I disorder and those with long-term schizophrenia have poorer neurocognitive function, even when clinically stable. Individuals with long-term bipolar I disorder and those with long-term schizophrenia have similar levels of deficits in several domains of neurocognitive function.
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Affiliation(s)
- Pei-Yun Lin
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Psychiatry, School of Medicine, and Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Peng-Wei Wang
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Psychiatry, School of Medicine, and Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Sheng Chen
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Psychiatry, School of Medicine, and Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Fang Yen
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Psychiatry, School of Medicine, and Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Fowdar JY, Grealy R, Lu Y, Griffiths LR. A genome-wide association study of essential hypertension in an Australian population using a DNA pooling approach. Mol Genet Genomics 2016; 292:307-324. [PMID: 27866268 DOI: 10.1007/s00438-016-1274-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 11/10/2016] [Indexed: 01/11/2023]
Abstract
Despite the success of genome-wide association studies (GWAS) in detecting genetic loci involved in complex traits, few susceptibility genes have been detected for essential hypertension (EH). We aimed to use pooled DNA GWAS approach to identify and validate novel genomic loci underlying EH susceptibility in an Australian case-control population. Blood samples and questionnaires detailing medical history, blood pressure, and prescribed medications were collected for 409 hypertensives and 409 age-, sex- and ethnicity-matched normotensive controls. Case and control DNA were pooled in quadruplicate and hybridized to Illumina 1 M-Duo arrays. Allele frequencies agreed with those reported in reference data and known EH association signals were represented in the top-ranked SNPs more frequently than expected by chance. Validation showed that pooled DNA GWAS gave reliable estimates of case and control allele frequencies. Although no markers reached Bonferroni-corrected genome-wide significance levels (5.0 × 10-8), the top marker rs34870220 near ASGR1 approached significance (p = 4.32 × 10-7), as did several candidate loci (p < 1 × 10-6) on chromosomes 2, 4, 6, 9, 12, and 17. Four markers (located in or near genes NHSL1, NKFB1, GLI2, and LRRC10) from the top ten ranked SNPs were individually genotyped in pool samples and were tested for association between cases and controls using the χ 2 test. Of these, rs1599961 (NFKB1) and rs12711538 (GLI2) showed significant difference between cases and controls (p < 0.01). Additionally, four top-ranking markers within NFKB1 were found to be in LD, suggesting a single strong association signal for this gene.
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Affiliation(s)
- Javed Y Fowdar
- School of Medical Science, Griffith University, Gold Coast, Australia
| | - Rebecca Grealy
- School of Medical Science, Griffith University, Gold Coast, Australia
| | - Yi Lu
- Genetic Epidemiology Department, Queensland Institute of Medical Research, Brisbane, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, Brisbane, QLD, 4059, Australia.
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12
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A genome-wide analysis of putative functional and exonic variation associated with extremely high intelligence. Mol Psychiatry 2016; 21:1145-51. [PMID: 26239293 PMCID: PMC4650257 DOI: 10.1038/mp.2015.108] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 05/21/2015] [Accepted: 06/16/2015] [Indexed: 02/07/2023]
Abstract
Although individual differences in intelligence (general cognitive ability) are highly heritable, molecular genetic analyses to date have had limited success in identifying specific loci responsible for its heritability. This study is the first to investigate exome variation in individuals of extremely high intelligence. Under the quantitative genetic model, sampling from the high extreme of the distribution should provide increased power to detect associations. We therefore performed a case-control association analysis with 1409 individuals drawn from the top 0.0003 (IQ >170) of the population distribution of intelligence and 3253 unselected population-based controls. Our analysis focused on putative functional exonic variants assayed on the Illumina HumanExome BeadChip. We did not observe any individual protein-altering variants that are reproducibly associated with extremely high intelligence and within the entire distribution of intelligence. Moreover, no significant associations were found for multiple rare alleles within individual genes. However, analyses using genome-wide similarity between unrelated individuals (genome-wide complex trait analysis) indicate that the genotyped functional protein-altering variation yields a heritability estimate of 17.4% (s.e. 1.7%) based on a liability model. In addition, investigation of nominally significant associations revealed fewer rare alleles associated with extremely high intelligence than would be expected under the null hypothesis. This observation is consistent with the hypothesis that rare functional alleles are more frequently detrimental than beneficial to intelligence.
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13
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Jernigan TL, Brown TT, Bartsch H, Dale AM. Toward an integrative science of the developing human mind and brain: Focus on the developing cortex. Dev Cogn Neurosci 2016; 18:2-11. [PMID: 26347228 PMCID: PMC4762760 DOI: 10.1016/j.dcn.2015.07.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/17/2015] [Accepted: 07/28/2015] [Indexed: 11/24/2022] Open
Abstract
Based on the Huttenlocher lecture, this article describes the need for a more integrative scientific paradigm for addressing important questions raised by key observations made over 2 decades ago. Among these are the early descriptions by Huttenlocher of variability in synaptic density in cortex of postmortem brains of children of different ages and the almost simultaneous reports of cortical volume reductions on MR imaging in children and adolescents. In spite of much progress in developmental neurobiology, developmental cognitive neuroscience, and behavioral and imaging genetics, we still do not know how these early observations relate to each other. It is argued that large scale, collaborative research programs are needed to establish the associations between behavioral differences among children and imaging biomarkers, and to link the latter to cellular changes in the developing brain. Examples of progress and challenges remaining are illustrated with data from the Pediatric Imaging, Neurocognition, and Genetics Project (PING).
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Affiliation(s)
- Terry L Jernigan
- Center for Human Development, University of California, San Diego, La Jolla, CA, United States; Department of Cognitive Science, University of California, San Diego, La Jolla, CA, United States; Department of Psychiatry, University of California, San Diego, La Jolla, CA, United States; Department of Radiology, University of California, San Diego, La Jolla, CA, United States.
| | - Timothy T Brown
- Multimodal Imaging Laboratory, University of California, San Diego, La Jolla, CA, United States; Department of Neurosciences, University of California, San Diego, La Jolla, CA, United States
| | - Hauke Bartsch
- Multimodal Imaging Laboratory, University of California, San Diego, La Jolla, CA, United States
| | - Anders M Dale
- Department of Cognitive Science, University of California, San Diego, La Jolla, CA, United States; Department of Radiology, University of California, San Diego, La Jolla, CA, United States; Multimodal Imaging Laboratory, University of California, San Diego, La Jolla, CA, United States; Department of Neurosciences, University of California, San Diego, La Jolla, CA, United States
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14
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Mayo O. Interaction between Genotype and Environment: A Tale of Two Concepts. T ROY SOC SOUTH AUST 2015. [DOI: 10.1080/03721426.2011.10887151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Craig IW, Haworth CMA, Plomin R. Commentary on "A Role for the X Chromosome in Sex Differences in Variability in General Intelligence?" (Johnson et al., 2009). PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2015; 4:615-21. [PMID: 26161737 DOI: 10.1111/j.1745-6924.2009.01170.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Johnson et al.'s (2009) article highlights the role of X-chromosomal genes in general intelligence and draws attention to their potential role in explaining the observed greater variance for this trait in males and their excess at both extremes of the distribution. We note that this would result from a simple additive effect of X-linked intelligence genes and also discuss the potentially important contribution of recessive deleterious loci. The buffering effect of heterozygosity in females will be partly constrained by the skewing of X-inactivation patterns increasing the variance of females beyond what is expected. Furthermore, escape of some X-linked genes from in-activation may also be relevant to male-female variance comparisons. We also comment on the difficulty of establishing the extent to which the X chromosome is enriched for intelligence genes and point out that their estimates of the proportion of genes influencing general intelligence that might be located on the X chromosome rely on some doubtful premises, especially concerning the likely equivalence of X-linked gene action in males and females. Finally, we discuss the increasingly compelling evidence for the accumulation of genes on the X chromosome that have selective benefit to males, including those implicated infertility and some manifestations of intelligence.
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Affiliation(s)
- Ian W Craig
- Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, London, United Kingdom
| | - Claire M A Haworth
- Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, London, United Kingdom
| | - Robert Plomin
- Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, London, United Kingdom
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Johnson W, Carothers A, Deary IJ. A Role for the X Chromosome in Sex Differences in Variability in General Intelligence? PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2015; 4:598-611. [PMID: 26161735 DOI: 10.1111/j.1745-6924.2009.01168.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
There is substantial evidence that males are more variable than females in general intelligence. In recent years, researchers have presented this as a reason that, although there is little, if any, mean sex difference in general intelligence, males tend to be overrepresented at both ends of its overall distribution. Part of the explanation could be the presence of genes on the X chromosome related both to syndromal disorders involving mental retardation and to population variation in general intelligence occurring normally. Genes on the X chromosome appear overrepresented among genes with known involvement in mental retardation, which is consistent with a model we developed of the population distribution of general intelligence as a mixture of two normal distributions. Using this model, we explored the expected ratios of males to females at various points in the distribution and estimated the proportion of variance in general intelligence potentially due to genes on the X chromosome. These estimates provide clues to the extent to which biologically based sex differences could be manifested in the environment as sex differences in displayed intellectual abilities. We discuss these observations in the context of sex differences in specific cognitive abilities and evolutionary theories of sexual selection.
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Affiliation(s)
- Wendy Johnson
- University of Edinburgh, United Kingdom University of Minnesota-Twin Cities, and
| | - Andrew Carothers
- Public Health Sciences, University of Edinburgh Medical School, United Kingdom
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17
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Gash DM, Deane AS. Neuron-based heredity and human evolution. Front Neurosci 2015; 9:209. [PMID: 26136649 PMCID: PMC4469835 DOI: 10.3389/fnins.2015.00209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/26/2015] [Indexed: 11/22/2022] Open
Abstract
It is widely recognized that human evolution has been driven by two systems of heredity: one DNA-based and the other based on the transmission of behaviorally acquired information via nervous system functions. The genetic system is ancient, going back to the appearance of life on Earth. It is responsible for the evolutionary processes described by Darwin. By comparison, the nervous system is relatively newly minted and in its highest form, responsible for ideation and mind-to-mind transmission of information. Here the informational capabilities and functions of the two systems are compared. While employing quite different mechanisms for encoding, storing and transmission of information, both systems perform these generic hereditary functions. Three additional features of neuron-based heredity in humans are identified: the ability to transfer hereditary information to other members of their population, not just progeny; a selection process for the information being transferred; and a profoundly shorter time span for creation and dissemination of survival-enhancing information in a population. The mechanisms underlying neuron-based heredity involve hippocampal neurogenesis and memory and learning processes modifying and creating new neural assemblages changing brain structure and functions. A fundamental process in rewiring brain circuitry is through increased neural activity (use) strengthening and increasing the number of synaptic connections. Decreased activity in circuitry (disuse) leads to loss of synapses. Use and disuse modifying an organ to bring about new modes of living, habits and functions are processes in line with Neolamarckian concepts of evolution (Packard, 1901). Evidence is presented of bipartite evolutionary processes-Darwinian and Neolamarckian-driving human descent from a common ancestor shared with the great apes.
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Affiliation(s)
- Don M. Gash
- Department of Anatomy and Neurobiology, College of Medicine, University of KentuckyLexington, KY, USA
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Franić S, Groen-Blokhuis MM, Dolan CV, Kattenberg MV, Pool R, Xiao X, Scheet PA, Ehli EA, Davies GE, van der Sluis S, Abdellaoui A, Hansell NK, Martin NG, Hudziak JJ, van Beijsterveldt CEM, Swagerman SC, Hulshoff Pol HE, de Geus EJC, Bartels M, Ropers HH, Hottenga JJ, Boomsma DI. Intelligence: shared genetic basis between Mendelian disorders and a polygenic trait. Eur J Hum Genet 2015; 23:1378-83. [PMID: 25712083 DOI: 10.1038/ejhg.2015.3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 12/16/2014] [Accepted: 12/25/2014] [Indexed: 11/09/2022] Open
Abstract
Multiple inquiries into the genetic etiology of human traits indicated an overlap between genes underlying monogenic disorders (eg, skeletal growth defects) and those affecting continuous variability of related quantitative traits (eg, height). Extending the idea of a shared genetic basis between a Mendelian disorder and a classic polygenic trait, we performed an association study to examine the effect of 43 genes implicated in autosomal recessive cognitive disorders on intelligence in an unselected Dutch population (N=1316). Using both single-nucleotide polymorphism (SNP)- and gene-based association testing, we detected an association between intelligence and the genes of interest, with genes ELP2, TMEM135, PRMT10, and RGS7 showing the strongest associations. This is a demonstration of the relevance of genes implicated in monogenic disorders of intelligence to normal-range intelligence, and a corroboration of the utility of employing knowledge on monogenic disorders in identifying the genetic variability underlying complex traits.
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Affiliation(s)
- Sanja Franić
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Maria M Groen-Blokhuis
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Conor V Dolan
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands.,Department of Psychological Methods, University of Amsterdam, Amsterdam, The Netherlands
| | - Mathijs V Kattenberg
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - René Pool
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Xiangjun Xiao
- Division of OVP, Cancer Prevention and Population Sciences, Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Paul A Scheet
- Division of OVP, Cancer Prevention and Population Sciences, Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Erik A Ehli
- Avera Institute for Human Genetics, Avera McKennan Hospital, University Health Center, Sioux Falls, SD, USA
| | - Gareth E Davies
- Avera Institute for Human Genetics, Avera McKennan Hospital, University Health Center, Sioux Falls, SD, USA
| | - Sophie van der Sluis
- Section Functional Genomics, Department of Clinical Genetics, VU Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Abdel Abdellaoui
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Narelle K Hansell
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, Queensland Institute of Medical Research, Brisbane, Australia
| | - Nicholas G Martin
- Genetic Epidemiology, Molecular Epidemiology and Neurogenetics Laboratories, Queensland Institute of Medical Research, Brisbane, Australia
| | - James J Hudziak
- Department of Psychiatry and Medicine, University of Vermont, Burlington, VT, USA
| | | | - Suzanne C Swagerman
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Hilleke E Hulshoff Pol
- Neuroimaging Research Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Eco J C de Geus
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Meike Bartels
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - H Hilger Ropers
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Jouke-Jan Hottenga
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
| | - Dorret I Boomsma
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands
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Results of a "GWAS plus:" general cognitive ability is substantially heritable and massively polygenic. PLoS One 2014; 9:e112390. [PMID: 25383866 PMCID: PMC4226546 DOI: 10.1371/journal.pone.0112390] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 05/04/2014] [Indexed: 11/24/2022] Open
Abstract
We carried out a genome-wide association study (GWAS) for general cognitive ability (GCA) plus three other analyses of GWAS data that aggregate the effects of multiple single-nucleotide polymorphisms (SNPs) in various ways. Our multigenerational sample comprised 7,100 Caucasian participants, drawn from two longitudinal family studies, who had been assessed with an age-appropriate IQ test and had provided DNA samples passing quality screens. We conducted the GWAS across ∼2.5 million SNPs (both typed and imputed), using a generalized least-squares method appropriate for the different family structures present in our sample, and subsequently conducted gene-based association tests. We also conducted polygenic prediction analyses under five-fold cross-validation, using two different schemes of weighting SNPs. Using parametric bootstrapping, we assessed the performance of this prediction procedure under the null. Finally, we estimated the proportion of variance attributable to all genotyped SNPs as random effects with software GCTA. The study is limited chiefly by its power to detect realistic single-SNP or single-gene effects, none of which reached genome-wide significance, though some genomic inflation was evident from the GWAS. Unit SNP weights performed about as well as least-squares regression weights under cross-validation, but the performance of both increased as more SNPs were included in calculating the polygenic score. Estimates from GCTA were 35% of phenotypic variance at the recommended biological-relatedness ceiling. Taken together, our results concur with other recent studies: they support a substantial heritability of GCA, arising from a very large number of causal SNPs, each of very small effect. We place our study in the context of the literature–both contemporary and historical–and provide accessible explication of our statistical methods.
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20
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Why expert performance is special and cannot be extrapolated from studies of performance in the general population: A response to criticisms. INTELLIGENCE 2014. [DOI: 10.1016/j.intell.2013.12.001] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Harlaar N, Meaburn EL, Hayiou-Thomas ME, Davis OSP, Docherty S, Hanscombe KB, Haworth CMA, Price TS, Trzaskowski M, Dale PS, Plomin R. Genome-wide association study of receptive language ability of 12-year-olds. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2014; 57:96-105. [PMID: 24687471 PMCID: PMC3974169 DOI: 10.1044/1092-4388(2013/12-0303)] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
PURPOSE Researchers have previously shown that individual differences in measures of receptive language ability at age 12 are highly heritable. In the current study, the authors attempted to identify some of the genes responsible for the heritability of receptive language ability using a genome-wide association approach. METHOD The authors administered 4 Internet-based measures of receptive language (vocabulary, semantics, syntax, and pragmatics) to a sample of 2,329 twelve-year-olds for whom DNA and genome-wide genotyping were available. Nearly 700,000 single-nucleotide polymorphisms (SNPs) and 1 million imputed SNPs were included in a genome-wide association analysis of receptive language composite scores. RESULTS No SNP associations met the demanding criterion of genome-wide significance that corrects for multiple testing across the genome ( p < 5 × 10 -8). The strongest SNP association did not replicate in an additional sample of 2,639 twelve-year-olds. CONCLUSIONS These results indicate that individual differences in receptive language ability in the general population do not reflect common genetic variants that account for more than 3% of the phenotypic variance. The search for genetic variants associated with language skill will require larger samples and additional methods to identify and functionally characterize the full spectrum of risk variants.
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22
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Benyamin B, Pourcain BS, Davis OS, Davies G, Hansell NK, Brion MJA, Kirkpatrick RM, Cents RAM, Franić S, Miller MB, Haworth CMA, Meaburn E, Price TS, Evans DM, Timpson N, Kemp J, Ring S, McArdle W, Medland SE, Yang J, Harris SE, Liewald DC, Scheet P, Xiao X, Hudziak JJ, de Geus EJC, Jaddoe VWV, Starr JM, Verhulst FC, Pennell C, Tiemeier H, Iacono WG, Palmer LJ, Montgomery GW, Martin NG, Boomsma DI, Posthuma D, McGue M, Wright MJ, Smith GD, Deary IJ, Plomin R, Visscher PM. Childhood intelligence is heritable, highly polygenic and associated with FNBP1L. Mol Psychiatry 2014; 19:253-8. [PMID: 23358156 PMCID: PMC3935975 DOI: 10.1038/mp.2012.184] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 10/28/2012] [Accepted: 11/12/2012] [Indexed: 01/11/2023]
Abstract
Intelligence in childhood, as measured by psychometric cognitive tests, is a strong predictor of many important life outcomes, including educational attainment, income, health and lifespan. Results from twin, family and adoption studies are consistent with general intelligence being highly heritable and genetically stable throughout the life course. No robustly associated genetic loci or variants for childhood intelligence have been reported. Here, we report the first genome-wide association study (GWAS) on childhood intelligence (age range 6-18 years) from 17,989 individuals in six discovery and three replication samples. Although no individual single-nucleotide polymorphisms (SNPs) were detected with genome-wide significance, we show that the aggregate effects of common SNPs explain 22-46% of phenotypic variation in childhood intelligence in the three largest cohorts (P=3.9 × 10(-15), 0.014 and 0.028). FNBP1L, previously reported to be the most significantly associated gene for adult intelligence, was also significantly associated with childhood intelligence (P=0.003). Polygenic prediction analyses resulted in a significant correlation between predictor and outcome in all replication cohorts. The proportion of childhood intelligence explained by the predictor reached 1.2% (P=6 × 10(-5)), 3.5% (P=10(-3)) and 0.5% (P=6 × 10(-5)) in three independent validation cohorts. Given the sample sizes, these genetic prediction results are consistent with expectations if the genetic architecture of childhood intelligence is like that of body mass index or height. Our study provides molecular support for the heritability and polygenic nature of childhood intelligence. Larger sample sizes will be required to detect individual variants with genome-wide significance.
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Affiliation(s)
- B Benyamin
- The University of Queensland, Queensland Brain Institute, St Lucia, Queensland, Australia
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - BSt Pourcain
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - OS Davis
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - G Davies
- Department of Psychology, University of Edinburgh, Edinburgh, Scotland, UK
| | - NK Hansell
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - M-JA Brion
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
- School of Women's and Infants' Health, The University of Western Australia, Perth, Western Australia, Australia
| | - RM Kirkpatrick
- Department of Psychology, University of Minnesota, St Paul, MN, USA
| | - RAM Cents
- The Generation R Study Group, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Child and Adolescent Psychiatry, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - S Franić
- Netherlands Twin Register, Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - MB Miller
- Department of Psychology, University of Minnesota, St Paul, MN, USA
| | - CMA Haworth
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - E Meaburn
- Department of Psychology, Birkbeck University of London, London, UK
| | - TS Price
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - DM Evans
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - N Timpson
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - J Kemp
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - S Ring
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - W McArdle
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - SE Medland
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - J Yang
- The University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - SE Harris
- Molecular Medicine Centre, Institute for Genetics and Molecular Medicine Centre, University of Edinburgh, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - DC Liewald
- Department of Psychology, University of Edinburgh, Edinburgh, Scotland, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - P Scheet
- Netherlands Twin Register, Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - X Xiao
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - JJ Hudziak
- Department of Psychiatry, College of Medicine, University of Vermont, Burlington, VT, USA
| | - EJC de Geus
- Netherlands Twin Register, Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - VWV Jaddoe
- The Generation R Study Group, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Pediatrics, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - JM Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
- Alzheimer Scotland Dementia Research Centre, Department of Psychology, University of Edinburgh, Edinburgh, Scotland, UK
| | - FC Verhulst
- Department of Child and Adolescent Psychiatry, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - C Pennell
- School of Women's and Infants' Health, The University of Western Australia, Perth, Western Australia, Australia
| | - H Tiemeier
- Department of Child and Adolescent Psychiatry, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Psychiatry, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - WG Iacono
- Department of Psychology, University of Minnesota, St Paul, MN, USA
| | - LJ Palmer
- Genetic Epidemiology and Biostatistics Platform, Ontario Institute for Cancer Research, University of Toronto, Toronto, Ontario, Canada
- Samuel Lunenfeld Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - GW Montgomery
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - NG Martin
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - DI Boomsma
- Netherlands Twin Register, Department of Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - D Posthuma
- Department of Child and Adolescent Psychiatry, Erasmus MC-University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam (NCA), VU University Amsterdam and VU Medical Centre, Amsterdam, The Netherlands
- Department of Clinical Genetics, Section Medical Genomics, VU Medical Centre, Amsterdam, The Netherlands
| | - M McGue
- Department of Psychology, University of Minnesota, St Paul, MN, USA
- Department of Epidemiology, University of Southern Denmark, Odense, Denmark
| | - MJ Wright
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - G Davey Smith
- Medical Research Council Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK
| | - IJ Deary
- Department of Psychology, University of Edinburgh, Edinburgh, Scotland, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - R Plomin
- King's College London, Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK
| | - PM Visscher
- The University of Queensland, Queensland Brain Institute, St Lucia, Queensland, Australia
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
- The University of Queensland Diamantina Institute, Princess Alexandra Hospital, Brisbane, Queensland, Australia
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
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Kirkpatrick RM, McGue M, Iacono WG, Miller MB, Basu S, Pankratz N. Low-Frequency Copy-Number Variants and General Cognitive Ability: No Evidence of Association. INTELLIGENCE 2014; 42:98-106. [PMID: 24497650 PMCID: PMC3909536 DOI: 10.1016/j.intell.2013.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Although twin, family, and adoption studies have shown that general cognitive ability (GCA) is substantially heritable, GWAS has not uncovered a genetic polymorphism replicably associated with this phenotype. However, most polymorphisms used in GWAS are common SNPs. The present study explores use of a different class of genetic variant, the copy-number variant (CNV), to predict GCA in a sample of 6,199 participants, combined from two longitudinal family studies. We aggregated low-frequency (<5%) CNV calls into eight different mutational burden scores, each reflecting a different operationalization of mutational burden. We further conducted three genome-wide association scans, each of which utilized a different subset of identified low-frequency CNVs. Association signals from the burden analyses were generally small in effect size, and none were statistically significant after a careful Type I error correction was applied. No signal from the genome-wide scans significantly differed from zero at the adjusted Type I error rate. Thus, the present study provides no evidence that CNVs underlie heritable variance in GCA, though we cannot rule out the possibility of very rare or small-effect CNVs for this trait, which would require even larger samples to detect. We interpret these null results in light of recent breakthroughs that aggregate SNP effects to explain much, but not all, of the heritable variance in some quantitative traits.
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Affiliation(s)
- Robert M. Kirkpatrick
- University of Minnesota Department of Psychology, 75 E. River Rd, Minneapolis, MN 55455
| | - Matt McGue
- University of Minnesota Department of Psychology, 75 E. River Rd, Minneapolis, MN 55455
| | - William G. Iacono
- University of Minnesota Department of Psychology, 75 E. River Rd, Minneapolis, MN 55455
| | - Michael B. Miller
- University of Minnesota Department of Psychology, 75 E. River Rd, Minneapolis, MN 55455
| | - Saonli Basu
- University of Minnesota School of Public Health, Division of Biostatistics, 420 Delaware St SE, Minneapolis, MN 55455
| | - Nathan Pankratz
- University of Minnesota Medical School, Department of Laboratory Medicine & Pathology, 420 Delaware St. SE, Minneapolis, MN 55455
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Hill SK, Reilly JL, Keefe RSE, Gold JM, Bishop JR, Gershon ES, Tamminga CA, Pearlson GD, Keshavan MS, Sweeney JA. Neuropsychological impairments in schizophrenia and psychotic bipolar disorder: findings from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study. Am J Psychiatry 2013; 170:1275-84. [PMID: 23771174 PMCID: PMC5314430 DOI: 10.1176/appi.ajp.2013.12101298] [Citation(s) in RCA: 264] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Familial neuropsychological deficits are well established in schizophrenia but remain less well characterized in other psychotic disorders. This study from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) consortium 1) compares cognitive impairment in schizophrenia and bipolar disorder with psychosis, 2) tests a continuum model of cognitive dysfunction in psychotic disorders, 3) reports familiality of cognitive impairments across psychotic disorders, and 4) evaluates cognitive impairment among nonpsychotic relatives with and without cluster A personality traits. METHOD Participants included probands with schizophrenia (N=293), psychotic bipolar disorder (N=227), schizoaffective disorder (manic, N=110; depressed, N=55), their first-degree relatives (N=316, N=259, N=133, and N=64, respectively), and healthy comparison subjects (N=295). All participants completed the Brief Assessment of Cognition in Schizophrenia (BACS) neuropsychological battery. RESULTS Cognitive impairments among psychotic probands, compared to healthy comparison subjects, were progressively greater from bipolar disorder (z=-0.77) to schizoaffective disorder (manic z=-1.08; depressed z=-1.25) to schizophrenia (z=-1.42). Profiles across subtests of the BACS were similar across disorders. Familiality of deficits was significant and comparable in schizophrenia and bipolar disorder. Of particular interest were similar levels of neuropsychological deficits in relatives with elevated cluster A personality traits across proband diagnoses. Nonpsychotic relatives of schizophrenia probands without these personality traits exhibited significant cognitive impairments, while relatives of bipolar probands did not. CONCLUSIONS Robust cognitive deficits are present and familial in schizophrenia and psychotic bipolar disorder. Severity of cognitive impairments across psychotic disorders was consistent with a continuum model, in which more prominent affective features and less enduring psychosis were associated with less cognitive impairment. Cognitive dysfunction in first-degree relatives is more closely related to psychosis-spectrum personality disorder traits in psychotic bipolar disorder than in schizophrenia.
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Donohoe G, Deary IJ, Glahn DC, Malhotra AK, Burdick KE. Neurocognitive phenomics: examining the genetic basis of cognitive abilities. Psychol Med 2013; 43:2027-2036. [PMID: 23194477 DOI: 10.1017/s0033291712002656] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cognitive deficits are core to the disability associated with many psychiatric disorders. Both variation in cognition and psychiatric risk show substantial heritability, with overlapping genetic variants contributing to both. Unsurprisingly, therefore, these fields have been mutually beneficial : just as cognitive studies of psychiatric risk variants may identify genes involved in cognition, so too can genome-wide studies based on cognitive phenotypes lead to genes relevant to psychiatric aetiology. The purpose of this review is to consider the main issues involved in the phenotypic characterization of cognition, and to describe the challenges associated with the transition to genomewide approaches. We conclude by describing the approaches currently being taken by the international consortia involving many investigators in the field internationally (e.g. Cognitive Genomics Consortium; COGENT) to overcome these challenges.
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Affiliation(s)
- G Donohoe
- Department of Psychiatry, School of Medicine and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Republic of Ireland.
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26
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Barral S, Cosentino S, Costa R, Andersen SL, Christensen K, Eckfeldt JH, Newman AB, Perls TT, Province MA, Hadley EC, Rossi WK, Mayeux R. Exceptional memory performance in the Long Life Family Study. Neurobiol Aging 2013; 34:2445-8. [PMID: 23759147 DOI: 10.1016/j.neurobiolaging.2013.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 05/01/2013] [Indexed: 10/26/2022]
Abstract
Research to understand variability at the highest end of the cognitive performance distribution has been scarce. Our aim was to define a cognitive endophenotype based on exceptional episodic memory (EM) performance and to investigate familial aggregation of EM in families from the Long Life Family Study (LLFS). Using a sample of 1911 nondemented offspring of long-lived probands, we created a quantitative phenotype, EM (memory z ≥ 1.5), and classified LLFS families as EM and non-EM families based on the number of EM offspring. We then assessed differences in memory performance between LLFS relatives in the parental generation of EM families and those in non-EM families using multivariate analysis adjusted for APOE Apolipoprotein E genotype. LLFS relatives in the proband generation from EM families showed better EM performance than those from non-EM families (β = 0.74, standard error = 0.19, p = 1.4 × 10(-4)). We demonstrated that there is a familial correlation of the EM endophenotype, suggesting that genetic variants might influence memory performance in long-lived families.
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Affiliation(s)
- Sandra Barral
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, Department of Neurology, New York, NY 10032, USA.
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27
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Stenberg A. Interpreting estimates of heritability--a note on the twin decomposition. ECONOMICS AND HUMAN BIOLOGY 2013; 11:201-205. [PMID: 22676967 DOI: 10.1016/j.ehb.2012.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 03/31/2012] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
While most outcomes may in part be genetically mediated, quantifying genetic heritability is a different matter. To explore data on twins and decompose the variation is a classical method to determine whether variation in outcomes, e.g. IQ or schooling, originate from genetic endowments or environmental factors. Despite some criticism, the model is still widely used. The critique is generally related to how estimates of heritability may encompass environmental mediation. This aspect is sometimes left implicit by authors even though its relevance for the interpretation is potentially profound. This short note is an appeal for clarity from authors when interpreting the magnitude of heritability estimates. It is demonstrated how disregarding existing theoretical contributions can easily lead to unnecessary misinterpretations and/or controversies. The key arguments are relevant also for estimates based on data of adopted children or from modern molecular genetics research.
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Affiliation(s)
- Anders Stenberg
- Stockholm University, Institute for Social Research, Stockholm, Sweden.
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Haworth CMA, Davis OSP, Plomin R. Twins Early Development Study (TEDS): a genetically sensitive investigation of cognitive and behavioral development from childhood to young adulthood. Twin Res Hum Genet 2013; 16:117-25. [PMID: 23110994 PMCID: PMC3817931 DOI: 10.1017/thg.2012.91] [Citation(s) in RCA: 213] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The Twins Early Development Study (TEDS) is a large longitudinal sample of twins born in England and Wales between 1994 and 1996. The focus of TEDS has been on cognitive and behavioral development, including difficulties in the context of normal development. TEDS began when multiple births were identified from birth records and the families were invited to take part in the study; 16,810 pairs of twins were originally enrolled in TEDS. More than 10,000 of these twin pairs remain enrolled in the study to date. DNA has been collected for more than 7,000 pairs, and genome-wide genotyping data for two million DNA markers are available for 3,500 individuals. The TEDS families have taken part in studies when the twins were aged 2, 3, 4, 7, 8, 9, 10, 12, 14, and 16 years of age. Data collection is currently underway to assess the adult destinations of the twins as they move from school to university and the workplace. Between January 2012 and December 2014, all of the TEDS twins will turn 18, and the study will transition to an adult sample. TEDS represents an outstanding resource for investigating the developmental effects of genes and environments on complex quantitative traits from childhood to young adulthood and beyond.
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Celec P, Tretinárová D, Minárik G, Ficek A, Szemes T, Lakatošová S, Schmidtová E, Turňa J, Kádaši Ľ, Ostatníková D. Genetic polymorphisms related to testosterone metabolism in intellectually gifted boys. PLoS One 2013; 8:e54751. [PMID: 23382957 PMCID: PMC3559825 DOI: 10.1371/journal.pone.0054751] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 12/18/2012] [Indexed: 12/31/2022] Open
Abstract
Prepubertal testosterone levels are lower in intellectually gifted boys. The aim of this pilot study was to analyze potential genetic factors related to testosterone metabolism in control and gifted boys. Intellectually gifted (IQ>130; n = 95) and control (n = 67) boys were genotyped. Polymorphisms of interests were chosen in genes including androgen and estrogen receptors, 5-alpha reductase, aromatase and sex hormone binding globulin. Significant differences between control and gifted boys in genotype distributions were found for ESR2 (rs928554) and SHBG (rs1799941). A significantly lower number of CAG repeats in the AR gene were found in gifted boys. Our results support the role of genetic factors related to testosterone metabolism in intellectual giftedness. Increased androgen signaling might explain previous results of lower testosterone levels in intellectually gifted boys and add to the understanding of variability in cognitive abilities.
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Affiliation(s)
- Peter Celec
- Institute of Molecular Biomedicine, Comenius University, Bratislava, Slovak Republic.
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Bagshaw ATM, Horwood LJ, Liu Y, Fergusson DM, Sullivan PF, Kennedy MA. No effect of genome-wide copy number variation on measures of intelligence in a New Zealand birth cohort. PLoS One 2013; 8:e55208. [PMID: 23383111 PMCID: PMC3559383 DOI: 10.1371/journal.pone.0055208] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 12/27/2012] [Indexed: 11/25/2022] Open
Abstract
Variation in human intelligence is approximately 50% heritable, but understanding of the genes involved is limited. Several forms of genetic variation remain under-studied in relation to intelligence, one of which is copy number variation (CNV). Using single-nucleotide polymorphism (SNP) -based microarrays, we genotyped CNVs genome-wide in a birth cohort of 723 New Zealanders, and correlated them with four intelligence-related phenotypes. We found no significant association for any common CNV after false discovery correction, which is consistent with previous work. In contrast to a previous study, however, we found no effect on any cognitive measure of rare CNV burden, defined as total number of bases inserted or deleted in CNVs rarer than 5%. We discuss possible reasons for this failure to replicate, including interaction between CNV and aging in determining the effects of rare CNVs. While our results suggest that no CNV assayable by SNP chips contributes more than a very small amount to variation in human intelligence, it remains possible that common CNVs in segmental duplication arrays, which are not well covered by SNP chips, are important contributors.
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Affiliation(s)
- Andrew T M Bagshaw
- Department of Pathology, University of Otago, Christchurch, New Zealand.
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Abstract
Revolution is brewing belatedly within the heartlands of the genetic determinist establishment still in denial about the fluid genome that makes identifying genes even for common disease well-nigh impossible. The fruitless hunt for intelligence genes serves to expose the poverty of an obsolete paradigm that is obstructing knowledge and preventing fruitful policies from being widely implemented. Genome-wide scans using state-of-the art technologies on extensive databases have failed to find a single gene for intelligence; instead, environment and maternal effects may account for most, if not all correlation among relatives, while identical twins diverge genetically and epigenetically throughout life. Abundant evidence points to the enormous potential for improving intellectual abilities (and health) through simple environmental and social interventions.
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Grisham W, Korey CA, Schottler NA, McCauley LB, Beatty J. Teaching neuroinformatics with an emphasis on quantitative locus analysis. JOURNAL OF UNDERGRADUATE NEUROSCIENCE EDUCATION : JUNE : A PUBLICATION OF FUN, FACULTY FOR UNDERGRADUATE NEUROSCIENCE 2012; 11:A119-25. [PMID: 23493834 PMCID: PMC3592744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Although powerful bioinformatics tools are available for free on the web and are used by neuroscience professionals on a daily basis, neuroscience students are largely ignorant of them. This Neuroinformatics module weaves together several bioinformatics tools to make a comprehensive unit. This unit encompasses quantifying a phenotype through a Quantitative Trait Locus (QTL) analysis, which links phenotype to loci on chromosomes that likely had an impact on the phenotype. Students then are able to sift through a list of genes in the region(s) of the chromosome identified by the QTL analysis and find a candidate gene that has relatively high expression in the brain region of interest. Once such a candidate gene is identified, students can find out more information about the gene, including the cells/layers in which it is expressed, the sequence of the gene, and an article about the gene. All of the resources employed are available at no cost via the internet. Didactic elements of this instructional module include genetics, neuroanatomy, Quantitative Trait Locus analysis, molecular techniques in neuroscience, and statistics-including multiple regression, ANOVA, and a bootstrap technique. This module was presented at the Faculty for Undergraduate Neuroscience (FUN) 2011 Workshop at Pomona College and can be accessed at http://mdcune.psych.ucla.edu/modules/bioinformatics.
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Affiliation(s)
- William Grisham
- Department of Psychology, UCLA, Los Angeles, CA 90095-1563;,Address correspondence to: William Grisham, Ph.D., Psychology Department, UCLA, 1285 Franz Hall, PO Box 951563, Los Angeles, CA 90095-1563.
| | | | | | - Lisa Beck McCauley
- Office of Institutional Research, Planning and Assessment, Immaculata University, Immaculata, PA 19345
| | - Jackson Beatty
- Department of Psychology, UCLA, Los Angeles, CA 90095-1563
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Chabris CF, Hebert BM, Benjamin DJ, Beauchamp J, Cesarini D, van der Loos M, Johannesson M, Magnusson PKE, Lichtenstein P, Atwood CS, Freese J, Hauser TS, Hauser RM, Christakis N, Laibson D. Most reported genetic associations with general intelligence are probably false positives. Psychol Sci 2012; 23:1314-23. [PMID: 23012269 PMCID: PMC3498585 DOI: 10.1177/0956797611435528] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
General intelligence (g) and virtually all other behavioral traits are heritable. Associations between g and specific single-nucleotide polymorphisms (SNPs) in several candidate genes involved in brain function have been reported. We sought to replicate published associations between g and 12 specific genetic variants (in the genes DTNBP1, CTSD, DRD2, ANKK1, CHRM2, SSADH, COMT, BDNF, CHRNA4, DISC1, APOE, and SNAP25) using data sets from three independent, well-characterized longitudinal studies with samples of 5,571, 1,759, and 2,441 individuals. Of 32 independent tests across all three data sets, only 1 was nominally significant. By contrast, power analyses showed that we should have expected 10 to 15 significant associations, given reasonable assumptions for genotype effect sizes. For positive controls, we confirmed accepted genetic associations for Alzheimer's disease and body mass index, and we used SNP-based calculations of genetic relatedness to replicate previous estimates that about half of the variance in g is accounted for by common genetic variation among individuals. We conclude that the molecular genetics of psychology and social science requires approaches that go beyond the examination of candidate genes.
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Genome-wide association study of intelligence: additive effects of novel brain expressed genes. J Am Acad Child Adolesc Psychiatry 2012; 51:432-440.e2. [PMID: 22449649 DOI: 10.1016/j.jaac.2012.01.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 01/12/2012] [Accepted: 01/18/2012] [Indexed: 01/19/2023]
Abstract
OBJECTIVE The purpose of the present study was to identify common genetic variants that are associated with human intelligence or general cognitive ability. METHOD We performed a genome-wide association analysis with a dense set of 1 million single-nucleotide polymorphisms (SNPs) and quantitative intelligence scores within an ancestrally homogeneous family sample of 656 individuals with at least one child affected by attention-deficit/hyperactivity disorder (ADHD). RESULTS Haplotype trend regression analysis with sliding four-SNP windows identified haplotypes of genome-wide significance in genes involved in synaptic signaling (KIF16B; p = 1.27E-08) and neurodevelopment (PAX5; p = 3.58E-08), and highlight findings from a recent genetic study of cognitive ability (RXRA; p = 7.7E-08; GYPC; p = 2.5E-07). Further interrogation of SNPs within top haplotypes reveals that the minor alleles are associated with higher intelligence, whereas others are associated with relatively lower (but still average range) intelligence. Effects of the eight genes are additive, as a greater number of the associated genotypes in a given individual predict higher intelligence (p = 5.36E-08) and account for 8% of variance in intelligence. CONCLUSIONS Analyses that examine additive genetic effects may be useful in identifying regions where the additive effects of SNPs have a significant effect on phenotype. These results describe novel variants and additive effects of genes involved in brain development on variability in intelligence within an ADHD sample. The precise mechanisms of these loci in relation to determining individual differences in general cognitive ability require further investigation.
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Abstract
Fourteen years ago, the first article on molecular genetics was published in this journal: Child Development, Molecular Genetics, andWhat to Do With Genes Once They Are Found (R. Plomin & M. Rutter, 1998). The goal of the article was to outline what developmentalists can do with genes once they are found. These new directions for developmental research are still relevant today. The problem lies with the phrase “once they are found”: It has been much more difficult than expected to identify genes responsible for the heritability of complex traits and common disorders, the so-called missing heritability problem. The present article considers reasons for the missing heritability problem and possible solutions.
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A splice site mutation in a gene encoding for PDK4, a mitochondrial protein, is associated with the development of dilated cardiomyopathy in the Doberman pinscher. Hum Genet 2012; 131:1319-25. [PMID: 22447147 DOI: 10.1007/s00439-012-1158-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 03/08/2012] [Indexed: 10/28/2022]
Abstract
Familial dilated cardiomyopathy is a primary myocardial disease that can result in the development of congestive heart failure and sudden cardiac death. Spontaneous animal models of familial dilated cardiomyopathy exist and the Doberman pinscher dog is one of the most commonly reported canine breeds. The objective of this study was to evaluate familial dilated cardiomyopathy in the Doberman pinscher dog using a genome-wide association study for a genetic alteration(s) associated with the development of this disease in this canine model. Genome-wide association analysis identified an area of statistical significance on canine chromosome 14 (p(raw) = 9.999e-05 corrected for genome-wide significance), fine-mapping of additional SNPs flanking this region localized a signal to 23,774,190-23,781,919 (p = 0.001) and DNA sequencing identified a 16-base pair deletion in the 5' donor splice site of intron 10 of the pyruvate dehydrogenase kinase 4 gene in affected dogs (p < 0.0001). Electron microscopy of myocardium from affected dogs demonstrated disorganization of the Z line, mild to moderate T tubule and sarcoplasmic reticulum dilation, marked pleomorphic mitochondrial alterations with megamitochondria, scattered mitochondria with whorling and vacuolization and mild aggregates of lipofuscin granules. In conclusion, we report the identification of a splice site deletion in the PDK4 gene that is associated with the development of familial dilated cardiomyopathy in the Doberman pinscher dog.
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Vinkhuyzen AAE, van der Sluis S, Maes HHM, Posthuma D. Reconsidering the heritability of intelligence in adulthood: taking assortative mating and cultural transmission into account. Behav Genet 2012; 42:187-98. [PMID: 21969232 PMCID: PMC3276760 DOI: 10.1007/s10519-011-9507-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Accepted: 09/15/2011] [Indexed: 12/31/2022]
Abstract
Heritability estimates of general intelligence in adulthood generally range from 75 to 85%, with all heritability due to additive genetic influences, while genetic dominance and shared environmental factors are absent, or too small to be detected. These estimates are derived from studies based on the classical twin design and are based on the assumption of random mating. Yet, considerable positive assortative mating has been reported for general intelligence. Unmodeled assortative mating may lead to biased estimates of the relative magnitude of genetic and environmental factors. To investigate the effects of assortative mating on the estimates of the variance components of intelligence, we employed an extended twin-family design. Psychometric IQ data were available for adult monozygotic and dizygotic twins, their siblings, the partners of the twins and siblings, and either the parents or the adult offspring of the twins and siblings (N = 1314). Two underlying processes of assortment were considered: phenotypic assortment and social homogamy. The phenotypic assortment model was slightly preferred over the social homogamy model, suggesting that assortment for intelligence is mostly due to a selection of mates on similarity in intelligence. Under the preferred phenotypic assortment model, the variance of intelligence in adulthood was not only due to non-shared environmental (18%) and additive genetic factors (44%) but also to non-additive genetic factors (27%) and phenotypic assortment (11%).This non-additive nature of genetic influences on intelligence needs to be accommodated in future GWAS studies for intelligence.
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Affiliation(s)
- Anna A E Vinkhuyzen
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, The Netherlands.
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Green AE, Kraemer DJM, Deyoung CG, Fossella JA, Gray JR. A gene-brain-cognition pathway: prefrontal activity mediates the effect of COMT on cognitive control and IQ. ACTA ACUST UNITED AC 2012; 23:552-9. [PMID: 22368081 DOI: 10.1093/cercor/bhs035] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A core thesis of cognitive neurogenetic research is that genetic effects on cognitive ability are mediated by specific neural functions, however, demonstrating neural mediation has proved elusive. Pairwise relationships between genetic variation and brain function have yielded heterogeneous findings to date. This heterogeneity indicates that a multiple mediator modeling approach may be useful to account for complex relationships involving function at multiple brain regions. This is relevant not only for characterizing healthy cognition but for modeling the complex neural pathways by which disease-related genetic effects are transmitted to disordered cognitive phenotypes in psychiatric illness. Here, in 160 genotyped functional magnetic resonance imaging participants, we used a multiple mediator model to test a gene-brain-cognition pathway by which activity in 4 prefrontal brain regions mediates the effects of catechol-O-methyltransferase (COMT) gene on cognitive control and IQ. Results provide evidence for gene-brain-cognition mediation and help delineate a pathway by which gene expression contributes to intelligence.
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Affiliation(s)
- Adam E Green
- Department of Psychology, Georgetown University, Washington, DC 20057, USA.
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LeBlanc M, Kulle B, Sundet K, Agartz I, Melle I, Djurovic S, Frigessi A, Andreassen OA. Genome-wide study identifies PTPRO and WDR72 and FOXQ1-SUMO1P1 interaction associated with neurocognitive function. J Psychiatr Res 2012; 46:271-8. [PMID: 22126837 DOI: 10.1016/j.jpsychires.2011.11.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 10/01/2011] [Accepted: 11/02/2011] [Indexed: 01/05/2023]
Abstract
BACKGROUND Several aspects of neurocognitive function have high heritability, but the molecular genetic mechanisms underlying neurocognition are not known. We performed a genome-wide association study (GWAS) to identify genes associated with neurocognition. METHODS 700 Subjects (schizophrenia spectrum disorder, n=190, bipolar disorder n=157 and healthy individuals n=353) were tested with an extensive neuropsychological test battery, and genotyped using the Affymetrix Genome-Wide Human SNP Array 6.0. After quality control, linear regression analysis of each of the 24 cognitive tests on the SNP dosage was performed, including age, gender, education and disease group as covariates. Additionally, 9 SNPs trending toward genome-wide significance were considered for epistatic interactions. RESULTS Four SNPs and 2 independent association signals achieving genome-wide significance were identified. Three intronic SNPs in PTPRO were associated with learning and memory (CVLT-II LDFR) (rs17222089, p=1.55×10(-8); rs11056571, p=1.68×10(-8); and rs2300290, p=1.09×10(-8)). rs719714 downstream of WDR72 was associated with executive functioning (CW-3: Inhibition, D-KEFS) (p=4.32×10(-8)). A highly significant epistatic interaction was found between rs9378605 upstream of FOXQ1 and rs11699311 downstream of SUMO1P1 for the Grooved Pegboard test (p=7.6×10(-14)). CONCLUSIONS We identified four novel loci associated with neurocognitive function and one novel epistatic interaction. The findings should be replicated in independent samples, but indicate a role of PTPRO in learning and memory, WDR72 with executive functioning, and an interaction between FOXQ1 and SUMO1P1 for psychomotor speed.
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Affiliation(s)
- Marissa LeBlanc
- Epi-Gen, Institute of Clinical Medicine, Akershus University Hospital, University of Oslo, Oslo, Norway.
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Parasuraman R, Jiang Y. Individual differences in cognition, affect, and performance: behavioral, neuroimaging, and molecular genetic approaches. Neuroimage 2012; 59:70-82. [PMID: 21569853 PMCID: PMC3482491 DOI: 10.1016/j.neuroimage.2011.04.040] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Revised: 04/12/2011] [Accepted: 04/19/2011] [Indexed: 11/30/2022] Open
Abstract
We describe the use of behavioral, neuroimaging, and genetic methods to examine individual differences in cognition and affect, guided by three criteria: (1) relevance to human performance in work and everyday settings; (2) interactions between working memory, decision-making, and affective processing; and (3) examination of individual differences. The results of behavioral, functional MRI (fMRI), event-related potential (ERP), and molecular genetic studies show that analyses at the group level often mask important findings associated with sub-groups of individuals. Dopaminergic/noradrenergic genes influencing prefrontal cortex activity contribute to inter-individual variation in working memory and decision behavior, including performance in complex simulations of military decision-making. The interactive influences of individual differences in anxiety, sensation seeking, and boredom susceptibility on evaluative decision-making can be systematically described using ERP and fMRI methods. We conclude that a multi-modal neuroergonomic approach to examining brain function (using both neuroimaging and molecular genetics) can be usefully applied to understanding individual differences in cognition and affect and has implications for human performance at work.
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Affiliation(s)
- Raja Parasuraman
- Arch Laboratory and Department of Psychology, George Mason University, Fairfax, VA 22030, USA.
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Clark L, Boxer O, Sahakian BJ, Bilder RM. Research methods: cognitive neuropsychological methods. HANDBOOK OF CLINICAL NEUROLOGY 2012; 106:75-87. [PMID: 22608616 DOI: 10.1016/b978-0-444-52002-9.00005-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Luke Clark
- Department of Experimental Psychology, University of Cambridge, Cambridge, UK.
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Johnson W, Penke L, Spinath FM. Heritability in the Era of Molecular Genetics: Some Thoughts for Understanding Genetic Influences on Behavioural Traits. EUROPEAN JOURNAL OF PERSONALITY 2011. [DOI: 10.1002/per.836] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Genetic influences on behavioural traits are ubiquitous. When behaviourism was the dominant paradigm in psychology, demonstrations of heritability of behavioural and psychological constructs provided important evidence of its limitations. Now that genetic influences on behavioural traits are generally accepted, we need to recognise the limitations of heritability as an indicator of both the aetiology and likelihood of discovering molecular genetic associations with behavioural traits. We review those limitations and conclude that quantitative genetics and genetically informative research designs are still critical to understanding the roles of gene–environment interplay in developmental processes, though not necessarily in the ways commonly discussed. Copyright © 2011 John Wiley & Sons, Ltd.
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Affiliation(s)
- Wendy Johnson
- Centre for Cognitive Ageing and Cognitive Epidemiology and Department of Psychology, University of Edinburgh, Edinburgh, UK
- Department of Psychology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Lars Penke
- Centre for Cognitive Ageing and Cognitive Epidemiology and Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Frank M. Spinath
- Department of Psychology, Saarland University, Saarbruecken, Germany
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Psychopathological aspects of dopaminergic gene polymorphisms in adolescence and young adulthood. Neurosci Biobehav Rev 2011; 35:1665-86. [PMID: 21527290 DOI: 10.1016/j.neubiorev.2011.04.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 04/08/2011] [Accepted: 04/10/2011] [Indexed: 02/01/2023]
Abstract
Dopamine hypotheses of several psychiatric disorders are based upon the clinical benefits of drugs affecting dopamine transporter or receptors, and have prompted intensive candidate gene research within the dopaminergic system during the last two decades. The aim of this review is to survey the most important findings concerning dopaminergic gene polymorphisms in attention deficit hyperactivity disorder (ADHD), Tourette syndrome (TS), obsessive compulsive disorder, and substance abuse. Also, genetic findings of related phenotypes, such as inattention, impulsivity, aggressive behavior, and novelty seeking personality trait are presented, because recent studies have applied quantitative trait measures using questionnaires, symptom scales, or other objective endophenotypes. Unfortunately, genetic variants with minor effects are problematic to detect in these complex inheritance disorders, often leading to contradictory results. The most consistent association findings relate to ADHD and the dopamine transporter and the dopamine D4 receptor genes. Meta-analyses also support the association between substance abuse and the D2 receptor gene. The dopamine catabolizing enzyme genes, such as monoamine oxidase (MAO) A and catechol-O-methyltransferase (COMT) genes, have been linked to aggressive behaviors.
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The efficacy of detecting variants with small effects on the Affymetrix 6.0 platform using pooled DNA. Hum Genet 2011; 130:607-21. [PMID: 21424828 DOI: 10.1007/s00439-011-0974-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 03/06/2011] [Indexed: 01/10/2023]
Abstract
Genome-wide genotyping of a cohort using pools rather than individual samples has long been proposed as a cost-saving alternative for performing genome-wide association (GWA) studies. However, successful disease gene mapping using pooled genotyping has thus far been limited to detecting common variants with large effect sizes, which tend not to exist for many complex common diseases or traits. Therefore, for DNA pooling to be a viable strategy for conducting GWA studies, it is important to determine whether commonly used genome-wide SNP array platforms such as the Affymetrix 6.0 array can reliably detect common variants of small effect sizes using pooled DNA. Taking obesity and age at menarche as examples of human complex traits, we assessed the feasibility of genome-wide genotyping of pooled DNA as a single-stage design for phenotype association. By individually genotyping the top associations identified by pooling, we obtained a 14- to 16-fold enrichment of SNPs nominally associated with the phenotype, but we likely missed the top true associations. In addition, we assessed whether genotyping pooled DNA can serve as an inexpensive screen as the second stage of a multi-stage design with a large number of samples by comparing the most cost-effective 3-stage designs with 80% power to detect common variants with genotypic relative risk of 1.1, with and without pooling. Given the current state of the specific technology we employed and the associated genotyping costs, we showed through simulation that a design involving pooling would be 1.07 times more expensive than a design without pooling. Thus, while a significant amount of information exists within the data from pooled DNA, our analysis does not support genotyping pooled DNA as a means to efficiently identify common variants contributing small effects to phenotypes of interest. While our conclusions were based on the specific technology and study design we employed, the approach presented here will be useful for evaluating the utility of other or future genome-wide genotyping platforms in pooled DNA studies.
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Beauchamp JP, Cesarini D, Johannesson M, Lindqvist E, Apicella C. On the sources of the height-intelligence correlation: new insights from a bivariate ACE model with assortative mating. Behav Genet 2011; 41:242-52. [PMID: 20603722 PMCID: PMC3044837 DOI: 10.1007/s10519-010-9376-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 06/14/2010] [Indexed: 12/25/2022]
Abstract
A robust positive correlation between height and intelligence, as measured by IQ tests, has been established in the literature. This paper makes several contributions toward establishing the causes of this association. First, we extend the standard bivariate ACE model to account for assortative mating. The more general theoretical framework provides several key insights, including formulas to decompose a cross-trait genetic correlation into components attributable to assortative mating and pleiotropy and to decompose a cross-trait within-family correlation. Second, we use a large dataset of male twins drawn from Swedish conscription records and examine how well genetic and environmental factors explain the association between (i) height and intelligence and (ii) height and military aptitude, a professional psychologist's assessment of a conscript's ability to deal with wartime stress. For both traits, we find suggestive evidence of a shared genetic architecture with height, but we demonstrate that point estimates are very sensitive to assumed degrees of assortative mating. Third, we report a significant within-family correlation between height and intelligence (p^ = 0.10), suggesting that pleiotropy might be at play.
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Rizzi TS, Arias-Vasquez A, Rommelse N, Kuntsi J, Anney R, Asherson P, Buitelaar J, Banaschewski T, Ebstein R, Ruano D, Van der Sluis S, Markunas CA, Garrett ME, Ashley-Koch AE, Kollins SH, Anastopoulos AD, Hansell NK, Wright MJ, Montgomery GW, Martin NG, Harris SE, Davies G, Tenesa A, Porteous DJ, Starr JM, Deary IJ, St Pourcain B, Davey Smith G, Timpson NJ, Evans DM, Gill M, Miranda A, Mulas F, Oades RD, Roeyers H, Rothenberger A, Sergeant J, Sonuga-Barke E, Steinhausen HC, Taylor E, Faraone SV, Franke B, Posthuma D. The ATXN1 and TRIM31 genes are related to intelligence in an ADHD background: evidence from a large collaborative study totaling 4,963 subjects. Am J Med Genet B Neuropsychiatr Genet 2011; 156:145-57. [PMID: 21302343 PMCID: PMC3085124 DOI: 10.1002/ajmg.b.31149] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 10/26/2010] [Indexed: 11/30/2022]
Abstract
Intelligence is a highly heritable trait for which it has proven difficult to identify the actual genes. In the past decade, five whole-genome linkage scans have suggested genomic regions important to human intelligence; however, so far none of the responsible genes or variants in those regions have been identified. Apart from these regions, a handful of candidate genes have been identified, although most of these are in need of replication. The recent growth in publicly available data sets that contain both whole genome association data and a wealth of phenotypic data, serves as an excellent resource for fine mapping and candidate gene replication. We used the publicly available data of 947 families participating in the International Multi-Centre ADHD Genetics (IMAGE) study to conduct an in silico fine mapping study of previously associated genomic locations, and to attempt replication of previously reported candidate genes for intelligence. Although this sample was ascertained for attention deficit/hyperactivity disorder (ADHD), intelligence quotient (IQ) scores were distributed normally. We tested 667 single nucleotide polymorphisms (SNPs) within 15 previously reported candidate genes for intelligence and 29451 SNPs in five genomic loci previously identified through whole genome linkage and association analyses. Significant SNPs were tested in four independent samples (4,357 subjects), one ascertained for ADHD, and three population-based samples. Associations between intelligence and SNPs in the ATXN1 and TRIM31 genes and in three genomic locations showed replicated association, but only in the samples ascertained for ADHD, suggesting that these genetic variants become particularly relevant to IQ on the background of a psychiatric disorder.
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Affiliation(s)
- Thais S Rizzi
- Department of Functional Genomics, CNCR, Neuroscience Campus Amsterdam, VU University and VU Medical Center, Amsterdam, the Netherlands.
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Ricci G, Astolfi A, Remondini D, Cipriani F, Formica S, Dondi A, Pession A. Pooled genome-wide analysis to identify novel risk loci for pediatric allergic asthma. PLoS One 2011; 6:e16912. [PMID: 21359210 PMCID: PMC3040188 DOI: 10.1371/journal.pone.0016912] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 01/03/2011] [Indexed: 11/22/2022] Open
Abstract
Background Genome-wide association studies of pooled DNA samples were shown to be a valuable tool to identify candidate SNPs associated to a phenotype. No such study was up to now applied to childhood allergic asthma, even if the very high complexity of asthma genetics is an appropriate field to explore the potential of pooled GWAS approach. Methodology/Principal Findings We performed a pooled GWAS and individual genotyping in 269 children with allergic respiratory diseases comparing allergic children with and without asthma. We used a modular approach to identify the most significant loci associated with asthma by combining silhouette statistics and physical distance method with cluster-adapted thresholding. We found 97% concordance between pooled GWAS and individual genotyping, with 36 out of 37 top-scoring SNPs significant at individual genotyping level. The most significant SNP is located inside the coding sequence of C5, an already identified asthma susceptibility gene, while the other loci regulate functions that are relevant to bronchial physiopathology, as immune- or inflammation-mediated mechanisms and airway smooth muscle contraction. Integration with gene expression data showed that almost half of the putative susceptibility genes are differentially expressed in experimental asthma mouse models. Conclusion/Significance Combined silhouette statistics and cluster-adapted physical distance threshold analysis of pooled GWAS data is an efficient method to identify candidate SNP associated to asthma development in an allergic pediatric population.
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Affiliation(s)
- Giampaolo Ricci
- Pediatric Unit, Department of Gynecologic, Obstetric and Pediatric Sciences, University of Bologna, Bologna, Italy.
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Added value measures in education show genetic as well as environmental influence. PLoS One 2011; 6:e16006. [PMID: 21311598 PMCID: PMC3032733 DOI: 10.1371/journal.pone.0016006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 12/01/2010] [Indexed: 11/22/2022] Open
Abstract
Does achievement independent of ability or previous attainment provide a purer measure of the added value of school? In a study of 4000 pairs of 12-year-old twins in the UK, we measured achievement with year-long teacher assessments as well as tests. Raw achievement shows moderate heritability (about 50%) and modest shared environmental influences (25%). Unexpectedly, we show that for indices of the added value of school, genetic influences remain moderate (around 50%), and the shared (school) environment is less important (about 12%). The pervasiveness of genetic influence in how and how much children learn is compatible with an active view of learning in which children create their own educational experiences in part on the basis of their genetic propensities.
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Wolf C, Jackson MC, Kissling C, Thome J, Linden DE. Dysbindin-1 genotype effects on emotional working memory. Mol Psychiatry 2011; 16:145-55. [PMID: 20010894 PMCID: PMC3044452 DOI: 10.1038/mp.2009.129] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 10/15/2009] [Accepted: 11/03/2009] [Indexed: 01/03/2023]
Abstract
We combined functional imaging and genetics to investigate the behavioral and neural effects of a dysbindin-1 (DTNBP1) genotype associated with the expression level of this important synaptic protein, which has been implicated in schizophrenia. On a working memory (WM) task for emotional faces, participants with the genotype related to increased expression showed higher WM capacity for happy faces compared with the genotype related to lower expression. Activity in several task-related brain areas with known DTNBP1 expression was increased, including hippocampal, temporal and frontal cortex. Although these increases occurred across emotions, they were mostly observed in areas whose activity correlated with performance for happy faces. This suggests effects of variability in DTNBP1 on emotion-specific WM capacity and region-specific task-related brain activation in humans. Synaptic effects of DTNBP1 implicate that altered dopaminergic and/or glutamatergic neurotransmission may be related to the increased WM capacity. The combination of imaging and genetics thus allows us to bridge the gap between the cellular/molecular and systems/behavioral level and extend the cognitive neuroscience approach to a comprehensive biology of cognition.
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Affiliation(s)
- Claudia Wolf
- Wolfson Centre for Cognitive and Clinical Neuroscience, School of Psychology, Bangor University, Brigantia Building, Bangor, LL57 2AS, UK
| | - Margaret C. Jackson
- Wolfson Centre for Cognitive and Clinical Neuroscience, School of Psychology, Bangor University, Brigantia Building, Bangor, LL57 2AS, UK
| | - Christian Kissling
- Laboratory of Molecular Psychiatry and Pharmacology, Institute of Life Science, School of Medicine, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Johannes Thome
- Laboratory of Molecular Psychiatry and Pharmacology, Institute of Life Science, School of Medicine, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - David E.J. Linden
- Wolfson Centre for Cognitive and Clinical Neuroscience, School of Psychology, Bangor University, Brigantia Building, Bangor, LL57 2AS, UK
- North Wales Clinical School, Bangor University, Bangor, LL57 2AS, UK
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Docherty SJ, Kovas Y, Plomin R. Gene-environment interaction in the etiology of mathematical ability using SNP sets. Behav Genet 2011; 41:141-54. [PMID: 20978832 PMCID: PMC3029801 DOI: 10.1007/s10519-010-9405-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 10/06/2010] [Indexed: 11/01/2022]
Abstract
Mathematics ability and disability is as heritable as other cognitive abilities and disabilities, however its genetic etiology has received relatively little attention. In our recent genome-wide association study of mathematical ability in 10-year-old children, 10 SNP associations were nominated from scans of pooled DNA and validated in an individually genotyped sample. In this paper, we use a 'SNP set' composite of these 10 SNPs to investigate gene-environment (GE) interaction, examining whether the association between the 10-SNP set and mathematical ability differs as a function of ten environmental measures in the home and school in a sample of 1888 children with complete data. We found two significant GE interactions for environmental measures in the home and the school both in the direction of the diathesis-stress type of GE interaction: The 10-SNP set was more strongly associated with mathematical ability in chaotic homes and when parents are negative.
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Affiliation(s)
- Sophia J Docherty
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College, London SE5 8AF, UK.
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