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Bandeira CE, das Neves FGP, Rovaris DL, Grevet EH, Dias-Soares M, da Silva C, Dresch F, da Silva BS, Bau CHD, Shansis FM, Genro JP, Contini V. The symptomatology of Attention-Deficit/Hyperactivity Disorder and the genetic control of vitamin D levels. Nutr Neurosci 2024:1-11. [PMID: 38761117 DOI: 10.1080/1028415x.2024.2351322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2024]
Abstract
OBJECTIVES Vitamin D deficiency has been associated with psychiatric disorders and behavioral phenotypes such as Attention-Deficit/Hyperactivity Disorder (ADHD). Considering that vitamin D levels are polygenic, we aim to evaluate the overall effects of its genetic architecture on symptoms of inattention, hyperactivity, and impulsivity and on the serum levels of vitamin D in two independent samples of adults, as well as the specific effects of five relevant polymorphisms in vitamin D-related genes. METHODS We evaluated 870 subjects from an ADHD sample (407 cases and 463 controls) and 319 subjects from an academic community (nutrigenetic sample). Vitamin D serum levels were obtained through Elisa test and genetic data by TaqMan™ allelic discrimination and Infinium PsychArray-24 BeadChip genotyping. Polygenic Scores (PGS) were calculated on PRSice2 based on the latest GWAS for Vitamin D and statistical analyses were conducted at Plink and SPSS software. RESULTS Vitamin D PGSs were associated with inattention in the ADHD sample and with hyperactivity when inattention symptoms were included as covariates. In the nutrigenetic sample, CYP2R1 rs10741657 and DHCR7 rs12785878 were nominally associated with impulsivity and hyperactivity, respectively, and both with vitamin D levels. In the clinical sample, RXRG rs2134095 was associated with impulsivity. DISCUSSION Our findings suggest a shared genetic architecture between vitamin D levels and ADHD symptoms, as evidenced by the associations observed with PGS and specific genes related to vitamin D levels. Interestingly, differential effects for vitamin D PGS were found in inattention and hyperactivity, which should be considered in further studies involving ADHD.
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Affiliation(s)
- Cibele Edom Bandeira
- ADHD Outpatient Program, Clinical Research Center, Department of Psychiatry, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | | | - Diego Luiz Rovaris
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Eugenio Horacio Grevet
- ADHD Outpatient Program, Clinical Research Center, Department of Psychiatry, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Department of Psychiatry, Faculty of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Graduate Program in Psychiatry and Behavioral Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Laboratory of Developmental Psychiatry, Center of Experimental Research, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Monique Dias-Soares
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Caroline da Silva
- Graduate Program in Biotechnology, Universidade do Vale do Taquari - Univates, Lajeado, Brazil
| | - Fabiane Dresch
- Graduate Program in Biotechnology, Universidade do Vale do Taquari - Univates, Lajeado, Brazil
| | - Bruna Santos da Silva
- ADHD Outpatient Program, Clinical Research Center, Department of Psychiatry, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Laboratory of Physiological Genomics of Mental Health (PhysioGen Lab), Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Claiton Henrique Dotto Bau
- ADHD Outpatient Program, Clinical Research Center, Department of Psychiatry, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Graduate Program in Genetics and Molecular Biology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Graduate Program in Psychiatry and Behavioral Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Laboratory of Developmental Psychiatry, Center of Experimental Research, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
- Department of Genetics and Molecular Biology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Flávio Milman Shansis
- Graduate Program in Medical Sciences, Universidade do Vale do Taquari (Univates), Lajeado, Brazil
| | - Júlia Pasqualini Genro
- Graduate Program in Biosciences, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Verônica Contini
- Graduate Program in Biotechnology, Universidade do Vale do Taquari - Univates, Lajeado, Brazil
- Graduate Program in Medical Sciences, Universidade do Vale do Taquari (Univates), Lajeado, Brazil
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Taylor MJ, Martin J, Butwicka A, Lichtenstein P, D'Onofrio B, Lundström S, Larsson H, Rosenqvist MA. A twin study of genetic and environmental contributions to attention-deficit/hyperactivity disorder over time. J Child Psychol Psychiatry 2023; 64:1608-1616. [PMID: 37409759 DOI: 10.1111/jcpp.13854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/16/2023] [Indexed: 07/07/2023]
Abstract
BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) is an increasingly commonly diagnosed neurodevelopmental condition. One possibility is that this reflects a genuine increase in the prevalence of ADHD due to secular environmental changes, yet this hypothesis remains untested. We therefore investigated whether the genetic and environmental variance underlying ADHD, and traits of ADHD, has changed over time. METHODS We identified twins born from 1982 to 2008 from the Swedish Twin Registry (STR). We linked the STR with the Swedish National Patient Register and Prescribed Drug Register to identify diagnoses of ADHD and prescriptions of ADHD medication for these twins. We also utilized data collected from participants in the Child and Adolescent Twin Study in Sweden (CATSS), born from 1992 to 2008. Their parents completed a structured ADHD screening tool, which was used to measure traits of ADHD and assign broad screening diagnoses of ADHD. We used the classical twin design to test whether the degree to which variation in these measures was influenced by genetic and environmental variation changed over time. RESULTS We included 22,678 twin pairs from the STR and 15,036 pairs from CATSS. The heritability of ADHD in the STR ranged from 66% to 86% over time, although these fluctuations were not statistically significant. We observed a modest increase in variance in ADHD traits, from 0.98 to 1.09. This was driven by small increases in the underlying genetic and environmental variance, with heritability estimated as 64%-65%. No statistically significant changes in variance in screening diagnoses were observed. CONCLUSIONS The relative contribution of genetic and environmental factors to ADHD has remained stable over time, despite its increasing prevalence. Thus, changes in the underlying etiology of ADHD over time are unlikely to explain the increase in ADHD diagnoses.
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Affiliation(s)
- Mark J Taylor
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Joanna Martin
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
| | - Agnieszka Butwicka
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Department of Child Psychiatry, Medical University of Warsaw, Warsaw, Poland
- Child and Adolescent Psychiatry, Stockholm Health Care Service, Region Stockholm, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Brian D'Onofrio
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Department of Psychological and Brain Science, Indiana University, Bloomington, IN, USA
| | - Sebastian Lundström
- Gillberg Neuropsychiatry Centre, Centre for Ethics, Law and Mental Health, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- School of Medical Sciences, Örebro University, Örebro, Sweden
| | - Mina A Rosenqvist
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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3
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Cao M, Martin E, Li X. Machine learning in attention-deficit/hyperactivity disorder: new approaches toward understanding the neural mechanisms. Transl Psychiatry 2023; 13:236. [PMID: 37391419 DOI: 10.1038/s41398-023-02536-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 06/19/2023] [Accepted: 06/21/2023] [Indexed: 07/02/2023] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent and heterogeneous neurodevelopmental disorder in children and has a high chance of persisting in adulthood. The development of individualized, efficient, and reliable treatment strategies is limited by the lack of understanding of the underlying neural mechanisms. Diverging and inconsistent findings from existing studies suggest that ADHD may be simultaneously associated with multivariate factors across cognitive, genetic, and biological domains. Machine learning algorithms are more capable of detecting complex interactions between multiple variables than conventional statistical methods. Here we present a narrative review of the existing machine learning studies that have contributed to understanding mechanisms underlying ADHD with a focus on behavioral and neurocognitive problems, neurobiological measures including genetic data, structural magnetic resonance imaging (MRI), task-based and resting-state functional MRI (fMRI), electroencephalogram, and functional near-infrared spectroscopy, and prevention and treatment strategies. Implications of machine learning models in ADHD research are discussed. Although increasing evidence suggests that machine learning has potential in studying ADHD, extra precautions are still required when designing machine learning strategies considering the limitations of interpretability and generalization.
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Affiliation(s)
- Meng Cao
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | | | - Xiaobo Li
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA.
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4
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Investigating the causal risk factors for self-harm by integrating Mendelian randomisation within twin modelling. Behav Genet 2022; 52:324-337. [DOI: 10.1007/s10519-022-10114-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 08/14/2022] [Indexed: 11/02/2022]
Abstract
AbstractPrevious genetically informed studies have uncovered likely causal relationships between mental health problems and self-harm but resulting causal estimates may be biased due to unmediated pleiotropy. By fitting Mendelian Randomization - Direction of Causation (MR-DoC) models that explicitly model pleiotropy, we investigated the effect of four quantitatively measured mental health problems - major depressive disorder (MDD), schizophrenia, attention-deficit hyperactivity disorder (ADHD), and insomnia, on non-suicidal self-harm (NSSH) and suicidal self-harm (SSH), separately. We used data of 12,723 twins (56.6% females) in the Twins Early Development Study. Besides substantial pleiotropy, we found effects from child-rated depressive symptoms to both NSSH (β = 0.194, 95% CIs: 0.131, 0.257) and SSH (β = 0.210, 95% CIs: 0.125, 0.295). Similarly, effects flowed from parent-rated depressive symptoms to NSSH (β = 0.092, 95% CIs: 0.004, 0.181) and SSH (β = 0.165, 95% CIs: 0.051, 0.281). We did not find evidence of aetiological difference between NSSH and SSH.
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Gray matter volumetric correlates of attention deficit and hyperactivity traits in emerging adolescents. Sci Rep 2022; 12:11367. [PMID: 35790754 PMCID: PMC9256746 DOI: 10.1038/s41598-022-15124-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 06/20/2022] [Indexed: 11/08/2022] Open
Abstract
Previous research has demonstrated reduction in cortical and subcortical, including basal ganglia (BG), gray matter volumes (GMV) in individuals with attention deficit hyperactivity disorder (ADHD), a neurodevelopmental condition that is more prevalent in males than in females. However, the volumetric deficits vary across studies. Whether volumetric reductions are more significant in males than females; to what extent these neural markers are heritable and relate to cognitive dysfunction in ADHD remain unclear. To address these questions, we followed published routines and performed voxel-based morphometry analysis of a data set (n = 11,502; 5,464 girls, 9–10 years) curated from the Adolescent Brain Cognition Development project, a population-based study of typically developing children. Of the sample, 634 and 2,826 were identified as monozygotic twins and dizygotic twins/siblings, respectively. In linear regressions, a cluster in the hypothalamus showed larger GMV, and bilateral caudate and putamen, lateral orbitofrontal and occipital cortex showed smaller GMVs, in correlation with higher ADHD scores in girls and boys combined. When examined separately, boys relative to girls showed more widespread (including BG) and stronger associations between GMV deficits and ADHD scores. ADHD traits and the volumetric correlates demonstrated heritability estimates (a2) between 0.59 and 0.79, replicating prior findings of the genetic basis of ADHD. Further, ADHD traits and the volumetric correlates (except for the hypothalamus) were each negatively and positively correlated with N-back performance. Together, these findings confirm volumetric deficits in children with more prominent ADHD traits. Highly heritable in both girls and boys and potentially more significant in boys than in girls, the structural deficits underlie diminished capacity in working memory and potentially other cognitive deficits in ADHD.
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Luo Y, Adamek JH, Crocetti D, Mostofsky SH, Ewen JB. Dissociation in Neural Correlates of Hyperactive/Impulsive vs. Inattentive Symptoms in Attention-Deficit/Hyperactivity Disorder. Front Neurosci 2022; 16:893239. [PMID: 35812240 PMCID: PMC9256983 DOI: 10.3389/fnins.2022.893239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 05/31/2022] [Indexed: 11/21/2022] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders characterized in current diagnostic criteria by two dominant symptoms, inattention and hyperactivity/impulsivity. Here, we show that task-related alpha (8-12 Hz) interhemispheric connectivity changes, as assessed during a unimanual finger-tapping task, is correlated with inattentive symptom severity (r = 0.55, p = 0.01) but not with severity of hyperactive/impulsive symptoms. Prior published analyses of the same dataset have already show that alpha event-related desynchronization (ERD) in the hemisphere contralateral to unimanual tapping is related to hyperactive/impulsive symptom severity (r = 0.43, p = 0.04) but not to inattentive symptom severity. Our findings demonstrate a neurobiological dissociation in ADHD symptom severity, with implications for understanding the structure of endophenotypes in the disorder as well as for biomarker development.
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Affiliation(s)
- Yu Luo
- Kennedy Krieger Institute, Baltimore, MD, United States.,School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Jack H Adamek
- Kennedy Krieger Institute, Baltimore, MD, United States
| | | | - Stewart H Mostofsky
- Kennedy Krieger Institute, Baltimore, MD, United States.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Joshua B Ewen
- Kennedy Krieger Institute, Baltimore, MD, United States.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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7
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Hare MM, Graziano PA. Treatment Response among Preschoolers with Disruptive Behavior Disorders: The Role of Temperament and Parenting. JOURNAL OF CLINICAL CHILD AND ADOLESCENT PSYCHOLOGY : THE OFFICIAL JOURNAL FOR THE SOCIETY OF CLINICAL CHILD AND ADOLESCENT PSYCHOLOGY, AMERICAN PSYCHOLOGICAL ASSOCIATION, DIVISION 53 2021; 50:950-965. [PMID: 33275456 PMCID: PMC8175459 DOI: 10.1080/15374416.2020.1846540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Objective: This study examined associations between temperament (negative affect, effortful control, and surgency) and symptoms of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) within a diverse preschool sample. Interactions between temperament and parenting in the prediction of ADHD/ODD symptoms before and after an 8-week early intervention program (i.e., Summer Treatment Program for Pre-kindergartners; STP-PreK) were also examined.Method: The sample included 215 children (Mage = 5.0, 80.9% male, 84.7% Latinx) with a diagnosis of ADHD and/or ODD who completed the STP-PreK. Temperament was measured via parent report while ADHD/ODD symptoms were assessed via combination of parent and teacher report. Positive and negative parenting were assessed via rating scales and a standardized parent-child interaction observation.Results: Higher surgency was associated with greater symptom severity of ADHD/ODD pre- and post-treatment. Higher negative affect was associated with greater symptom severity of ODD pre- and post-treatment, while higher effortful control was only associated with lower symptom severity of inattention pre-treatment. Positive parenting predicted lower symptom severity of ADHD/ODD post-treatment. Moderation analyses indicated that the benefits of low levels of negative parenting only occurred when paired with low temperament risk for symptoms of hyperactivity and ODD. Additionally, only the combination of high surgency and high observed negative parenting resulted in greater symptom severity of ODD. Finally, decreases in inconsistent discipline predicted decreases across all symptom domains post-treatment.Conclusions: Our findings add to the temperament-based model of ADHD/ODD by highlighting temperament's unique prediction of treatment response as well as important interactions with the caregiving environment.
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Affiliation(s)
- Megan M Hare
- Center for Children and Families, Department of Psychology, Florida International University
| | - Paulo A Graziano
- Center for Children and Families, Department of Psychology, Florida International University
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8
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Li L, Taylor MJ, Bälter K, Kuja‐Halkola R, Chen Q, Hegvik T, Tate AE, Chang Z, Arias‐Vásquez A, Hartman CA, Larsson H. Attention-deficit/hyperactivity disorder symptoms and dietary habits in adulthood: A large population-based twin study in Sweden. Am J Med Genet B Neuropsychiatr Genet 2020; 183:475-485. [PMID: 33029947 PMCID: PMC7702140 DOI: 10.1002/ajmg.b.32825] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/14/2020] [Accepted: 09/22/2020] [Indexed: 01/28/2023]
Abstract
Associations between adult attention-deficit/hyperactivity disorder (ADHD) symptoms and dietary habits have not been well established and the underlying mechanisms remain unclear. We explored these associations using a Swedish population-based twin study with 17,999 individuals aged 20-47 years. We estimated correlations between inattention and hyperactivity/impulsivity with dietary habits and fitted twin models to determine the genetic and environmental contributions. Dietary habits were defined as (a) consumption of food groups, (b) consumption of food items rich in particular macronutrients, and (c) healthy and unhealthy dietary patterns. At the phenotypic level, inattention was positively correlated with seafood, high-fat, high-sugar, high-protein food consumptions, and unhealthy dietary pattern, with correlation coefficients ranging from 0.03 (95%CI: 0.01, 0.05) to 0.13 (95% CI: 0.11, 0.15). Inattention was negatively correlated with fruits, vegetables consumptions and healthy dietary pattern, with correlation coefficients ranging from -0.06 (95%CI: -0.08, -0.04) to -0.07 (95%CI: -0.09, -0.05). Hyperactivity/impulsivity and dietary habits showed similar but weaker patterns compared to inattention. All associations remained stable across age, sex and socioeconomic status. Nonshared environmental effects contributed substantially to the correlations of inattention (56-60%) and hyperactivity/impulsivity (63-80%) with dietary habits. The highest and lowest genetic correlations were between inattention and high-sugar food (rA = .16, 95% CI: 0.07, 0.25), and between hyperactivity/impulsivity and unhealthy dietary pattern (rA = .05, 95% CI: -0.05, 0.14), respectively. We found phenotypic and etiological overlap between ADHD and dietary habits, although these associations were weak. Our findings contribute to a better understanding of common etiological pathways between ADHD symptoms and various dietary habits.
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Affiliation(s)
- Lin Li
- School of Medical SciencesÖrebro UniversityÖrebroSweden
| | - Mark J. Taylor
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Katarina Bälter
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden,Public Health SciencesMälardalen UniversityVästeråsSweden
| | - Ralf Kuja‐Halkola
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Qi Chen
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Tor‐Arne Hegvik
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden,Department of BiomedicineUniversity of BergenBergenNorway
| | - Ashley E. Tate
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Zheng Chang
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Alejandro Arias‐Vásquez
- The Department of Psychiatry & Human GeneticsDonders Institute for Brain, Cognition, and Behavior, Radboud University Medical CenterNijmegenNetherlands
| | - Catharina A. Hartman
- Department of PsychiatryUniversity of Groningen, University Medical Center GroningenGroningenNetherlands
| | - Henrik Larsson
- School of Medical SciencesÖrebro UniversityÖrebroSweden,Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
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9
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Brikell I, Larsson H, Lu Y, Pettersson E, Chen Q, Kuja-Halkola R, Karlsson R, Lahey BB, Lichtenstein P, Martin J. The contribution of common genetic risk variants for ADHD to a general factor of childhood psychopathology. Mol Psychiatry 2020; 25:1809-1821. [PMID: 29934545 PMCID: PMC6169728 DOI: 10.1038/s41380-018-0109-2] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 04/01/2018] [Accepted: 05/14/2018] [Indexed: 01/20/2023]
Abstract
Common genetic risk variants have been implicated in the etiology of clinical attention-deficit/hyperactivity disorder (ADHD) diagnoses and symptoms in the general population. However, given the extensive comorbidity across ADHD and other psychiatric conditions, the extent to which genetic variants associated with ADHD also influence broader psychopathology dimensions remains unclear. The aim of this study was to evaluate the associations between ADHD polygenic risk scores (PRS) and a broad range of childhood psychiatric symptoms, and to quantify the extent to which such associations can be attributed to a general factor of childhood psychopathology. We derived ADHD PRS for 13,457 children aged 9 or 12 from the Child and Adolescent Twin Study in Sweden, using results from an independent meta-analysis of genome-wide association studies of ADHD diagnosis and symptoms. We estimated associations between ADHD PRS, a general psychopathology factor, and several dimensions of neurodevelopmental, externalizing, and internalizing symptoms, using structural equation modeling. Higher ADHD PRS were statistically significantly associated with elevated neurodevelopmental, externalizing, and depressive symptoms (R2 = 0.26-1.69%), but not with anxiety. After accounting for a general psychopathology factor, on which all symptoms loaded positively (mean loading = 0.50, range = 0.09-0.91), an association with specific hyperactivity/impulsivity remained significant. ADHD PRS explained ~ 1% (p value < 0.0001) of the variance in the general psychopathology factor and ~ 0.50% (p value < 0.0001) in specific hyperactivity/impulsivity. Our results suggest that common genetic risk variants associated with ADHD, and captured by PRS, also influence a general genetic liability towards broad childhood psychopathology in the general population, in addition to a specific association with hyperactivity/impulsivity symptoms.
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Affiliation(s)
- Isabell Brikell
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- School of Medical Sciences, Örebro University, Örebro, Sweden
| | - Yi Lu
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Statistical Genetics, Genetics and Computational Biology Department, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Erik Pettersson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Qi Chen
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Ralf Kuja-Halkola
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Robert Karlsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Benjamin B Lahey
- Department of Public Health Sciences, University of Chicago, Chicago, IL, USA
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Joanna Martin
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
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10
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The (Broad-Sense) Genetic Correlations Among Four Measures of Inattention and Hyperactivity in 12 Year Olds. Behav Genet 2020; 50:273-288. [PMID: 32529491 PMCID: PMC7355270 DOI: 10.1007/s10519-020-10002-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 05/28/2020] [Indexed: 10/26/2022]
Abstract
We estimated the genetic covariance matrix among four inattention (INATT) and four hyperactivity (HYP) measures in the classical twin design. Data on INATT and HYP symptom counts were obtained in mono- and dizygotic twin pairs (N = 1593) with an average age of 12.2 years (sd = .51). We analyzed maternal ratings of INATT and HYP based on the Conners' Parent Rating Scale (CPRS), the Strengths and Weaknesses of ADHD-symptoms and Normal-behavior (SWAN), and teacher ratings based on the Conners' Teacher rating scale (CTRS) and the ASEBA Teacher Rating Form (TRF). Broad-sense heritabilities, corrected for the main effects of sex and for random teacher rater effects, were large (ranging from .658 to .912). The results reveal pervasive and strong broad-sense genetic effects on INATT and HYP phenotypes with the phenotypic covariance among the phenotypes largely due to correlated genetic effects. Specifically between 79.9 and 99.9% of the phenotypic covariance among the HYP measures, and between 81.0 and 93.5% of the INATT measures are attributable to broad-sense genetic effects. Overall, the present results, pertaining to the broad-sense heritabilities and shared genetic effects, support the current genome-wide association meta-analytic approach to identifying pleiotropic genetic variants.
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11
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Zheng Y, Pingault JB, Unger JB, Rijsdijk F. Genetic and environmental influences on attention-deficit/hyperactivity disorder symptoms in Chinese adolescents: a longitudinal twin study. Eur Child Adolesc Psychiatry 2020; 29:205-216. [PMID: 31111269 PMCID: PMC6864256 DOI: 10.1007/s00787-019-01346-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 05/07/2019] [Indexed: 10/26/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder. However, no study has examined genetic and environmental influences in the longitudinal developmental course of ADHD symptoms in a non-Western population. This study investigated changes of genetic and environmental influences and their contributions to the stability and change of ADHD symptoms of hyperactivity/impulsivity and inattention in Chinese adolescent twins. A prospective sample of 602 twin pairs (48% male) self-reported both DSM-IV ADHD symptom subscales three times at the approximate age of 12, 13, and 15 years. Longitudinal multivariate genetic analyses through structural equation modelling examined genetic and environmental contributions to the developmental course of ADHD symptoms. From early (time 1 and 2) to middle adolescence (time 3), both symptoms showed modest and non-significant genetic influences that became substantial and significant, whereas shared environmental influences were substantial and significant and became modest and non-significant. The same genetic factors influenced ADHD symptoms throughout adolescence, while shared and non-shared environmental influences largely came from new emerging factors. In early adolescence, genetic factor contributed to the stability of inattention, whereas shared environmental factor contributed to the stability of hyperactivity/impulsivity. Genetic influences of ADHD tended to be smaller, whereas shared environmental influences tended to be larger in Chinese than in Western populations. Genetic factors played a large role in the stability of ADHD throughout adolescence, while shared and non-shared environment primarily contributed to its change. Findings highlight the importance of shared family, neighbourhood, and community experiences on child psychopathology in a collectivistic culture such as the Chinese society.
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Affiliation(s)
- Yao Zheng
- Department of Psychology, University of Alberta, P-217 Biological Sciences Building, Edmonton, AB, T6G 2E9, Canada.
| | - Jean-Baptiste Pingault
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom,Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Jennifer B. Unger
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Frühling Rijsdijk
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
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Faraone SV, Larsson H. Genetics of attention deficit hyperactivity disorder. Mol Psychiatry 2019; 24:562-575. [PMID: 29892054 PMCID: PMC6477889 DOI: 10.1038/s41380-018-0070-0] [Citation(s) in RCA: 477] [Impact Index Per Article: 95.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 01/31/2018] [Accepted: 02/19/2018] [Indexed: 02/07/2023]
Abstract
Decades of research show that genes play an vital role in the etiology of attention deficit hyperactivity disorder (ADHD) and its comorbidity with other disorders. Family, twin, and adoption studies show that ADHD runs in families. ADHD's high heritability of 74% motivated the search for ADHD susceptibility genes. Genetic linkage studies show that the effects of DNA risk variants on ADHD must, individually, be very small. Genome-wide association studies (GWAS) have implicated several genetic loci at the genome-wide level of statistical significance. These studies also show that about a third of ADHD's heritability is due to a polygenic component comprising many common variants each having small effects. From studies of copy number variants we have also learned that the rare insertions or deletions account for part of ADHD's heritability. These findings have implicated new biological pathways that may eventually have implications for treatment development.
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Affiliation(s)
- Stephen V Faraone
- Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA.
| | - Henrik Larsson
- School of Medical Sciences, Örebro University, Örebro, Sweden
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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Taylor MJ, Martin J, Lu Y, Brikell I, Lundström S, Larsson H, Lichtenstein P. Association of Genetic Risk Factors for Psychiatric Disorders and Traits of These Disorders in a Swedish Population Twin Sample. JAMA Psychiatry 2019; 76:280-289. [PMID: 30566181 PMCID: PMC6439816 DOI: 10.1001/jamapsychiatry.2018.3652] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
IMPORTANCE Psychiatric traits associated with categorically defined psychiatric disorders are heritable and present to varying degrees in the general population. It is commonly assumed that diagnoses represent the extreme end of continuously distributed traits in the population, but this assumption has yet to be robustly tested for many psychiatric phenotypes. OBJECTIVE To assess whether genetic risk factors associated with psychiatric disorders are also associated with continuous variation in milder population traits. DESIGN, SETTING, AND PARTICIPANTS This study combined a novel twin analytic approach with polygenic risk score (PRS) analyses in a large population-based twin sample. Phenotypic and genetic data were available from the Child and Adolescent Twin Study in Sweden. Inpatient data were available for January 1, 1987, to December 31, 2014, and outpatient data for January 1, 2001, to December 31, 2013. The last day of follow-up was December 31, 2014. Data analysis was performed from January 1, 2017, to September 30, 2017. MAIN OUTCOMES AND MEASURES Questionnaires that assessed traits of autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), learning difficulties, tic disorders (TDs), obsessive-compulsive disorder (OCD), anxiety, major depressive disorder (MDD), mania, and psychotic experiences were administered to a large Swedish twin sample. Individuals with clinical psychiatric diagnoses were identified using the Swedish National Patient Register. Joint categorical/continuous twin modeling was used to estimate genetic correlations between psychiatric diagnoses and continuous traits. The PRSs for psychiatric disorders were calculated based on independent discovery genetic data. The association between PRSs for each disorder and associated continuous traits was tested. RESULTS Phenotype data were available for 13 923 twin pairs (35.1% opposite sex and 31.7% same-sex females) at 9 years of age, 5165 pairs (36.9% opposite sex and 34.0% same-sex females) at 15 years of age, and 4273 pairs (36.5% opposite sex and 34.4% same-sex females) at 18 years of age. Genetic data were available for 13 412 individuals (50.2% females). Twin genetic correlations between numerous psychiatric diagnoses and corresponding traits ranged from 0.31 to 0.69. Disorder PRSs were associated with related population traits for ASD (β [SE] = 0.04 [0.01] at 9 years of age), ADHD (β [SE] = 0.27 [0.03] at 9 years of age), TDs (β [SE] = 0.02 [0.004] at 9 years of age), OCD (β [SE] = 0.13 [0.05] at 18 years of age), anxiety (β [SE] = 0.18 [0.08] at 9 years of age; β [SE] = 0.07 [0.02] at 15 years of age; and β [SE] = 0.40 [0.17] at 18 years of age), MDD (β [SE] = 0.10 [0.03] at 9 years of age; β [SE] = 0.11 [0.02] at 15 years of age; and β [SE] = 0.41 [0.10] at 18 years of age), and schizophrenia (β [SE] = 0.02 [0.01] at 18 years of age). Polygenic risk scores for depressive symptoms were associated with MDD diagnoses (odds ratio, 1.16; 95% CI, 1.02-1.32). CONCLUSIONS AND RELEVANCE These results suggest that genetic factors associated with psychiatric disorders are also associated with milder variation in characteristic traits throughout the general population for many psychiatric phenotypes. This study suggests that many psychiatric disorders are likely to be continuous phenotypes rather than the categorical entities currently defined in diagnostic manuals, which has strong implications for genetic research in particular.
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Affiliation(s)
- Mark J. Taylor
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Joanna Martin
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden,MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, United Kingdom
| | - Yi Lu
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Isabell Brikell
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Sebastian Lundström
- Institute of Neuroscience and Physiology, Gillberg Neuropsychiatry Centre, Centre for Ethics Law and Mental Health, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden,School of Medical Sciences, Örebro University, Örebro, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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Liu CY, Li Y, Viding E, Asherson P, Pingault JB. The developmental course of inattention symptoms predicts academic achievement due to shared genetic aetiology: a longitudinal twin study. Eur Child Adolesc Psychiatry 2019; 28:367-375. [PMID: 30006673 DOI: 10.1007/s00787-018-1200-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 07/07/2018] [Indexed: 11/30/2022]
Abstract
Symptoms of attention-deficit hyperactivity disorder, in particular inattention symptoms, are associated with academic achievement. However, whether and why the developmental course of inattention symptoms (i.e. systematic decreases or increases of symptoms with age) predicts academic achievement remains unclear. A total of 5634 twin pairs born in the UK were included in the current study. We used latent growth curve modelling to estimate the baseline level and the developmental course of inattention symptoms (assessed at ages 8, 11, 14 and 16 years) and test whether they predicted the General Certificate of Secondary Education scores (GCSE, at age 16 years). We then implemented multivariate twin modelling to determine the role of genetic and environmental factors in explaining the relationship between inattention symptoms and GCSE scores. Increasing inattention symptoms across childhood and adolescence predicted poorer GCSE scores independently of the baseline level of inattention. Genetic factors explained most of this relationship, i.e. genetic factors contributing to individual differences in the developmental course of inattention also influenced GCSE scores. In conclusion, our study demonstrates that genetic factors underlying the developmental course of inattention symptoms across childhood and adolescence also influence academic achievement. This may result from indirect mechanism, whereby genetic factors explain systematic changes in inattention levels with age, which in turn impact academic achievement. The shared genetic aetiology may also suggest common neurobiological processes underlying both the developmental course of inattention symptoms and academic achievement.
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Affiliation(s)
- Chao-Yu Liu
- Division of Psychology and Language Sciences, Department of Clinical, Educational and Health Psychology, University College London, London, UK.,Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Yan Li
- Faculty of Psychology, Beijing Normal University, Beijing, China
| | - Essi Viding
- Division of Psychology and Language Sciences, Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Philip Asherson
- Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK
| | - Jean-Baptiste Pingault
- Division of Psychology and Language Sciences, Department of Clinical, Educational and Health Psychology, University College London, London, UK. .,Social, Genetic and Developmental Psychiatry Centre, King's College London, London, UK.
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Genetic and environmental aetiologies of associations between dispositional mindfulness and ADHD traits: a population-based twin study. Eur Child Adolesc Psychiatry 2019; 28:1241-1251. [PMID: 30758734 PMCID: PMC6751144 DOI: 10.1007/s00787-019-01279-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 01/12/2019] [Indexed: 12/20/2022]
Abstract
To get additional insight into the phenotype of attentional problems, we examined to what extent genetic and environmental factors explain covariation between lack of dispositional mindfulness and attention-deficit/hyperactivity disorder (ADHD) traits in youth, and explored the incremental validity of these constructs in predicting life satisfaction. We used data from a UK population-representative sample of adolescent twins (N = 1092 pairs) on lack of dispositional mindfulness [Mindful Attention Awareness Scale (MAAS)], ADHD traits [Conners' Parent Rating Scale-Revised (CPRS-R): inattentive (INATT) and hyperactivity/impulsivity (HYP/IMP) symptom dimensions] and life satisfaction (Students' Life Satisfaction Scale). Twin model fitting analyses were conducted. Phenotypic correlations (rp) between MAAS and CPRS-R (INATT: rp = 0.18, HYP/IMP: rp = 0.13) were small, but significant and largely explained by shared genes for INATT (% rp INATT-MAAS due to genes: 93%, genetic correlation rA = 0.37) and HYP/IMP (% rp HYP/IMP-MAAS due to genes: 81%; genetic correlation rA = 0.21) with no significant contribution of environmental factors. MAAS, INATT and HYP/IMP significantly and independently predicted life satisfaction. Lack of dispositional mindfulness, assessed as self-reported perceived lapses of attention (MAAS), taps into an aspect of attentional functioning that is phenotypically and genetically distinct from parent-rated ADHD traits. The clinically relevant incremental validity of both scales implicates that MAAS could be used to explore the underlying mechanisms of an aspect of attentional functioning that uniquely affects life satisfaction and is not captured by DSM-based ADHD scales. Further future research could identify if lack of dispositional mindfulness and high ADHD traits can be targeted by different therapeutic approaches resulting in different effects on life satisfaction.
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16
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The effects of vitamin D supplementation on ADHD (Attention Deficit Hyperactivity Disorder) in 6–13 year-old students: A randomized, double-blind, placebo-controlled study. Eur J Integr Med 2019. [DOI: 10.1016/j.eujim.2018.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Saudino KJ, Wang M, Flom M, Asherson P. Genetic and environmental links between motor activity level and attention problems in early childhood. Dev Sci 2018; 21:e12630. [PMID: 29119648 PMCID: PMC6693496 DOI: 10.1111/desc.12630] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 09/12/2017] [Indexed: 11/26/2022]
Abstract
Cross-lagged biometric models were used to examine genetic and environmental links between actigraph-assessed motor activity level (AL) and parent-rated attention problems (AP) in 314 same-sex twin pairs (MZ = 145, DZ = 169) at ages 2 and 3 years. At both ages, genetic correlations between AL and AP were moderate (ra2 = .35; ra3 = .39) indicating both overlap and specificity in genetic effects across the two domains. Within- and across-age phenotypic associations between AL and AP were entirely due to overlapping genetic influences. There was a unidirectional effect of AL at age 2 predicting later AP. For AP, genetic and environmental influences from age 2 were transmitted to age 3 via stability effects and from AL. For AL, across-age effects were transmitted only via stability. These results suggest that overactivity in late infancy may impact the later development of problems related to inattention, and that genetic factors explain the association between the two domains.
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Affiliation(s)
- Kimberly J. Saudino
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215
| | - Manjie Wang
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215
| | - Megan Flom
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215
| | - Philip Asherson
- Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Kings College, London, SE5 8AF
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18
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Ask H, Gustavson K, Ystrom E, Havdahl KA, Tesli M, Askeland RB, Reichborn-Kjennerud T. Association of Gestational Age at Birth With Symptoms of Attention-Deficit/Hyperactivity Disorder in Children. JAMA Pediatr 2018; 172:749-756. [PMID: 29946656 PMCID: PMC6142916 DOI: 10.1001/jamapediatrics.2018.1315] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 04/11/2018] [Indexed: 12/12/2022]
Abstract
Importance Preterm birth is associated with an increased risk of attention-deficit/hyperactivity disorder (ADHD); however, it is unclear to what extent this association can be explained by shared genetic and environmental risk factors and whether gestational age at birth is similarly related to inattention and hyperactivity/impulsivity and to the same extent in boys and girls. Objectives To investigate the association between gestational age at birth and symptoms of ADHD in preschool and school-age children after adjusting for unmeasured genetic and environmental risk factors. Design, Setting, and Participants In this prospective, population-based cohort study, pregnant women were recruited from across Norway from January 1, 1999, through December 31, 2008. Results of a conventional cohort design were compared with results from a sibling-comparison design (adjusting for genetic and environmental factors shared within families) using data from the Norwegian Mother and Child Cohort Study. Data analysis was performed from October 1, 2017, through March 16, 2018. Exposures Analyses compared children and siblings discordant for gestational age group: early preterm (delivery at gestational weeks 22-33), late preterm (delivery at gestational weeks 34-36), early term (delivery at gestational weeks 37-38), delivery at gestational week 39, reference group (delivery at gestational week 40), delivery at gestational week 41, and late term (delivery after gestational week 41). Main Outcomes and Measures Maternally reported symptoms of ADHD in children at 5 years of age and symptoms of inattention and hyperactivity/impulsivity at 8 years of age. Covariates included child and pregnancy characteristics associated with the week of delivery and the outcomes. Results A total of 113 227 children (55 187 [48.7%] female; 31 708 [28.0%] born at gestational week 40), including 33 081 siblings (16 014 female [48.4%]; 9705 [29.3%] born at gestational week 40), were included in the study. Children born early preterm were rated with more symptoms of ADHD, inattention, and hyperactivity/impulsivity than term-born children. After adjusting for unmeasured genetic and environmental factors, children born early preterm had a mean score that was 0.24 SD (95% CI, 0.14-0.34) higher on ADHD symptom tests, 0.33 SD (95% CI, 0.24-0.42) higher on inattention tests, and 0.23 SD (95% CI, 0.14-0.32) higher on hyperactivity/impulsivity tests compared with children born at gestational week 40. Sex moderated the association of gestational age with preschool ADHD symptoms, and the association appeared to be strongest among girls. Early preterm girls scored a mean of 0.8 SD (95% CI, 0.12-1.46; P = .02) higher compared with their term-born sisters. Conclusions and Relevance After accounting for unmeasured genetic and environmental factors, early preterm birth was associated with a higher level of ADHD symptoms in preschool children. Early premature birth was associated with inattentive but not hyperactive symptoms in 8-year-old children. This study demonstrates the importance of differentiating between inattention and hyperactivity/impulsivity and stratifying on sex in the study of childhood ADHD.
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Affiliation(s)
- Helga Ask
- Norwegian Institute of Public Health, Oslo, Norway
| | - Kristin Gustavson
- Norwegian Institute of Public Health, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Eivind Ystrom
- Norwegian Institute of Public Health, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Karoline Alexandra Havdahl
- Norwegian Institute of Public Health, Oslo, Norway
- MRC Integrative Epidemiology Unit, Bristol Medical School (Population Health Sciences), University of Bristol, Bristol, United Kingdom
| | - Martin Tesli
- Norwegian Institute of Public Health, Oslo, Norway
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | | | - Ted Reichborn-Kjennerud
- Norwegian Institute of Public Health, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
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Abstract
OBJECTIVE To evaluate the structural validity of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV). METHOD Confirmatory factor analyses were applied to a sample of 233 students diagnosed with ADHD by school multidisciplinary evaluation teams to evaluate the relative fit of the following competing models: (a) one factor, (b) two oblique verbal and nonverbal factors, (c) three oblique verbal, perceptual, and combined working memory/processing speed factors, (d) four oblique verbal, perceptual, working memory, and processing speed factors, (e) a higher-order model with four first-order factors, and (f) a bifactor model with four domain-specific factors. RESULTS A higher-order four-factor model fit the data best, which was composed of a general intelligence factor and four domain-specific factors that matched the four factors specified in the WISC-IV technical and interpretive manual. Moreover, the general intelligence factor explained more than two times the total variance contributed by all four domain-specific factors combined. CONCLUSIONS Results substantiate previous research on the WISC-IV, indicating that the general intelligence factor contributes the most reliable information. Consequently, it is recommended that interpretation of the WISC-IV remain at the Full-Scale IQ score level.
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20
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Xu B, Jia T, Macare C, Banaschewski T, Bokde ALW, Bromberg U, Büchel C, Cattrell A, Conrod PJ, Flor H, Frouin V, Gallinat J, Garavan H, Gowland P, Heinz A, Ittermann B, Martinot JL, Paillère Martinot ML, Nees F, Orfanos DP, Paus T, Poustka L, Smolka MN, Walter H, Whelan R, Schumann G, Desrivières S. Impact of a Common Genetic Variation Associated With Putamen Volume on Neural Mechanisms of Attention-Deficit/Hyperactivity Disorder. J Am Acad Child Adolesc Psychiatry 2017; 56:436-444.e4. [PMID: 28433093 DOI: 10.1016/j.jaac.2017.02.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 02/07/2017] [Accepted: 03/01/2017] [Indexed: 11/27/2022]
Abstract
OBJECTIVE In a recent genomewide association study of subcortical brain volumes, a common genetic variation at rs945270 was identified as having the strongest effect on putamen volume, a brain measurement linked to familial risk for attention-deficit/hyperactivity disorder (ADHD). To determine whether rs945270 might be a genetic determinant of ADHD, its effects on ADHD-related symptoms and neural mechanisms of ADHD, such as response inhibition and reward sensitivity, were explored. METHOD A large population sample of 1,834 14-year-old adolescents was used to test the effects of rs945270 on ADHD symptoms assessed through the Strengths and Difficulties Questionnaire and region-of-interest analyses of putamen activation by functional magnetic resonance imaging using the stop signal and monetary incentive delay tasks, assessing response inhibition and reward sensitivity, respectively. RESULTS There was a significant link between rs945270 and ADHD symptom scores, with the C allele associated with lower symptom scores, most notably hyperactivity. In addition, there were sex-specific effects of this variant on the brain. In boys, the C allele was associated with lower putamen activity during successful response inhibition, a brain response that was not associated with ADHD symptoms. In girls, putamen activation during reward anticipation increased with the number of C alleles, most significantly in the right putamen. Remarkably, right putamen activation during reward anticipation tended to negatively correlate with ADHD symptoms. CONCLUSION These results indicate that rs945270 might contribute to the genetic risk of ADHD partly through its effects on hyperactivity and reward processing in girls.
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Affiliation(s)
- Bing Xu
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Tianye Jia
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Christine Macare
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Tobias Banaschewski
- Clinical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, Germany
| | - Arun L W Bokde
- Discipline of Psychiatry, School of Medicine and the Trinity College Institute of Neurosciences, Trinity College Dublin, Ireland
| | - Uli Bromberg
- University Medical Centre Hamburg-Eppendorf, Germany
| | | | - Anna Cattrell
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Patricia J Conrod
- Université de Montreal, Centre Hospitalier Universitaire Sainte-Justine, Montreal, Canada
| | - Herta Flor
- Central Institute of Mental Health, Medical Faculty Mannheim, Germany
| | - Vincent Frouin
- Neurospin, Commissariat à l'Energie Atomique, CEA-Saclay Center, Paris, France
| | - Jürgen Gallinat
- University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Penny Gowland
- Sir Peter Mansfield Imaging Centre School of Physics and Astronomy, University of Nottingham, UK
| | - Andreas Heinz
- Campus Charité Mitte, Charité, Universitätsmedizin Berlin, Germany
| | - Bernd Ittermann
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany
| | - Jean-Luc Martinot
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1000 Neuroimaging and Psychiatry, University Paris Sud, University Paris Descartes, Sorbonne Paris Cité and Maison de Solenn, Paris
| | - Marie-Laure Paillère Martinot
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1000 Neuroimaging and Psychiatry, University Paris Sud, University Paris Descartes, Sorbonne Paris Cité and Maison de Solenn, Paris; Maison de Solenn, Cochin Hospital, Paris
| | - Frauke Nees
- Central Institute of Mental Health, Medical Faculty Mannheim, Germany
| | | | - Tomáš Paus
- Rotman Research Institute, Baycrest and the University of Toronto, Canada
| | - Luise Poustka
- Clinical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, Germany
| | | | - Henrik Walter
- Campus Charité Mitte, Charité, Universitätsmedizin Berlin, Germany
| | | | - Gunter Schumann
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Sylvane Desrivières
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK.
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Pinto R, Rijsdijk F, Ronald A, Asherson P, Kuntsi J. The Genetic Overlap of Attention-Deficit/Hyperactivity Disorder and Autistic-like Traits: an Investigation of Individual Symptom Scales and Cognitive markers. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2016; 44:335-45. [PMID: 26021462 PMCID: PMC4729813 DOI: 10.1007/s10802-015-0037-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASDs) frequently co-occur. However, due to previous exclusionary diagnostic criteria, little is known about the underlying causes of this covariation. Twin studies assessing ADHD symptoms and autistic-like traits (ALTs) suggest substantial genetic overlap, but have largely failed to take into account the genetic heterogeneity of symptom subscales. This study aimed to clarify the phenotypic and genetic relations between ADHD and ASD by distinguishing between symptom subscales that characterise the two disorders. Moreover, we aimed to investigate whether ADHD-related cognitive impairments show a relationship with ALT symptom subscales; and whether potential shared cognitive impairments underlie the genetic risk shared between the ADHD and ALT symptoms. Multivariate structural equation modelling was conducted on a population-based sample of 1312 twins aged 7–10. Social-communication ALTs correlated moderately with both ADHD symptom domains (phenotypic correlations around 0.30) and showed substantial genetic overlap with both inattention and hyperactivity-impulsivity (genetic correlation = 0.52 and 0.44, respectively). In addition to previously reported associations with ADHD traits, reaction time variability (RTV) showed significant phenotypic (0.18) and genetic (0.32) association with social-communication ALTs. RTV captured a significant proportion (24 %) of the genetic influences shared between inattention and social-communication ALTs. Our findings suggest that social-communication ALTs underlie the previously observed phenotypic and genetic covariation between ALTs and ADHD symptoms. RTV is not specific to ADHD symptoms, but is also associated with social-communication ALTs and can, in part, contribute to an explanation of the co-occurrence of ASD and ADHD.
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Affiliation(s)
- Rebecca Pinto
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Fruhling Rijsdijk
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Angelica Ronald
- Department of Psychological Sciences, Birkbeck, University of London, London, UK
| | - Philip Asherson
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK
| | - Jonna Kuntsi
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, De Crespigny Park, SE5 8AF, London, UK.
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22
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Pinto R, Asherson P, Ilott N, Cheung CHM, Kuntsi J. Testing for the mediating role of endophenotypes using molecular genetic data in a twin study of ADHD traits. Am J Med Genet B Neuropsychiatr Genet 2016; 171:982-92. [PMID: 27230021 PMCID: PMC5031223 DOI: 10.1002/ajmg.b.32463] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/12/2016] [Indexed: 11/11/2022]
Abstract
Family and twin studies have identified endophenotypes that capture familial and genetic risk in attention-deficit/hyperactivity disorder (ADHD), but it remains unclear if they lie on the causal pathway. Here, we illustrate a stepwise approach to identifying intermediate phenotypes. First, we use previous quantitative genetic findings to delineate the expected pattern of genetically correlated phenotypes. Second, we identify overlapping genetic associations with ADHD-related quantitative traits. Finally, we test for the mediating role of associated endophenotypes. We applied this approach to a sample of 1,312 twins aged 7-10. Based on previous twin model-fitting analyses, we selected hyperactivity-impulsivity, inattention, reading difficulties (RD), reaction time variability (RTV) and commission errors (CE), and tested for association with selected ADHD risk alleles. For nominally significant associations with both a symptom and a cognitive variable, matching the expected pattern based on previous genetic correlations, we performed mediation analysis to distinguish pleiotropic from mediating effects. The strongest association was observed for the rs7984966 SNP in the serotonin receptor gene (HTR2A), and RTV (P = 0.007; unadjusted for multiple testing). Mediation analysis suggested that CE (38%) and RTV (44%) substantially mediated the association between inattention and the T-allele of SNP rs3785157 in the norepinephrine transporter gene (SLC6A2) and the T-allele of SNP rs7984966 in HTR2A, respectively. The SNPs tag risk-haplotypes but are not thought to be functionally significant. While these exploratory findings are preliminary, requiring replication, this study demonstrates the value of this approach that can be adapted to the investigation of multiple genetic markers and polygenic risk scores. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Rebecca Pinto
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Nicholas Ilott
- The Kennedy Institute of Rheumatology; University of Oxford; Oxford UK
| | - Celeste H. M. Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience; King's College London; London UK
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23
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Bralten J, Greven CU, Franke B, Mennes M, Zwiers MP, Rommelse NN, Hartman C, van der Meer D, O’Dwyer L, Oosterlaan J, Hoekstra PJ, Heslenfeld D, Arias-Vasquez A, Buitelaar JK. Voxel-based morphometry analysis reveals frontal brain differences in participants with ADHD and their unaffected siblings. J Psychiatry Neurosci 2016; 41:272-9. [PMID: 26679925 PMCID: PMC4915936 DOI: 10.1503/jpn.140377] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Data on structural brain alterations in patients with attention-deficit/hyperactivity disorder (ADHD) have been inconsistent. Both ADHD and brain volumes have a strong genetic loading, but whether brain alterations in patients with ADHD are familial has been underexplored. We aimed to detect structural brain alterations in adolescents and young adults with ADHD compared with healthy controls. We examined whether these alterations were also found in their unaffected siblings, using a uniquely large sample. METHODS We performed voxel-based morphometry analyses on MRI scans of patients with ADHD, their unaffected siblings and typically developing controls. We identified brain areas that differed between participants with ADHD and controls and investigated whether these areas were different in unaffected siblings. Influences of medication use, age, sex and IQ were considered. RESULTS Our sample included 307 patients with ADHD, 169 unaffected siblings and 196 typically developing controls (mean age 17.2 [range 8-30] yr). Compared with controls, participants with ADHD had significantly smaller grey matter volume in 5 clusters located in the precentral gyrus, medial and orbitofrontal cortex, and (para)cingulate cortices. Unaffected siblings showed intermediate volumes significantly different from controls in 4 of these clusters (all except the precentral gyrus). Medication use, age, sex and IQ did not have an undue influence on the results. LIMITATIONS Our sample was heterogeneous, most participants with ADHD were taking medication, and the comparison was cross-sectional. CONCLUSION Brain areas involved in decision making, motivation, cognitive control and motor functioning were smaller in participants with ADHD than in controls. Investigation of unaffected siblings indicated familiality of 4 of the structural brain differences, supporting their potential in molecular genetic analyses in ADHD research.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Jan K. Buitelaar
- Correspondence to: J. Buitelaar, Department of Cognitive Neuroscience (126), Radboud University Medical center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands;
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24
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Taylor MJ, Lichtenstein P, Larsson H, Anckarsäter H, Greven CU, Ronald A. Is There a Female Protective Effect Against Attention-Deficit/Hyperactivity Disorder? Evidence From Two Representative Twin Samples. J Am Acad Child Adolesc Psychiatry 2016; 55:504-512.e2. [PMID: 27238069 PMCID: PMC4896985 DOI: 10.1016/j.jaac.2016.04.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/23/2016] [Accepted: 04/01/2016] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Attention-deficit/hyperactivity disorder (ADHD) is more frequent in males than in females. The "female protective effect" posits that females undergo greater exposure to etiological factors than males in order to develop ADHD, leading to the prediction that relatives of females with ADHD will display more ADHD behaviors. We thus tested whether cotwins of females displaying extreme ADHD traits would display more ADHD traits than cotwins of males displaying extreme ADHD traits. METHOD Parents of approximately 7,000 pairs of nonidentical twins in Sweden, and approximately 4,000 pairs of twins in England and Wales, completed dimensional assessments of ADHD traits. Probands were selected on the basis of scoring within the highest 10% of the distribution in each sample. Dimensional scores of cotwins of probands, as well as the categorical recurrence rate, were investigated by proband sex. RESULTS Cotwins of female probands displayed higher mean ADHD trait scores (mean = 0.62-0.79) than cotwins of male probands (mean = 0.38-0.55) in both samples. This trend was significant in the Swedish sample (p < .01) and when the 2 samples were merged into a single, larger sample (p < .001). When the samples were merged, there was also a significant association between proband sex and cotwin's categorical status, with more cotwins of female probands also being probands than cotwins of male probands. CONCLUSION These findings support a female protective effect against ADHD behaviors, suggesting that females require greater exposure to genetic and environmental factors associated with ADHD in order to develop the condition.
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Affiliation(s)
| | | | | | - Henrik Anckarsäter
- Centre for Ethics, Law and Mental Health (CELAM), University of Gothenburg, Gothenburg, Sweden
| | - Corina U. Greven
- Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands; Karakter Child and Adolescent Psychiatry Center, Nijmegen; and King’s College London, Medical Research Council Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, London
| | - Angelica Ronald
- Centre for Brain and Cognitive Development, Birkbeck, University of London.
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25
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The aetiological association between the dynamics of cortisol productivity and ADHD. J Neural Transm (Vienna) 2016; 123:991-1000. [PMID: 27106905 PMCID: PMC5005391 DOI: 10.1007/s00702-016-1534-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 02/23/2016] [Indexed: 11/25/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) has been linked to dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis, indexed by salivary cortisol. The phenotypic and aetiological association of cortisol productivity with ADHD was investigated. A selected twin design using 68 male twin-pairs aged 12–15, concordant or discordant for high ADHD symptom scores, or control twin-pairs with low ADHD symptoms, based on developmentally stable parental ADHD ratings. A genetic growth curve model was applied to cortisol samples obtained across three points during a cognitive-electroencephalography assessment, to examine the aetiological overlap of ADHD affection status (high versus low ADHD symptom scores) with latent intercept and slope factors. A significant phenotypic correlation emerged between ADHD and the slope factor, with cortisol levels dropping faster for the group with high ADHD symptom scores. The analyses further suggested this overlap was mostly driven by correlated genetic effects. We identified change in cortisol activity over time as significantly associated with ADHD affection status, primarily explained by shared genetic effects, suggesting that blunted cortisol productivity can be a marker of genetic risk in ADHD.
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26
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Greven CU, Merwood A, van der Meer JMJ, Haworth CMA, Rommelse N, Buitelaar JK. The opposite end of the attention deficit hyperactivity disorder continuum: genetic and environmental aetiologies of extremely low ADHD traits. J Child Psychol Psychiatry 2016; 57:523-31. [PMID: 26474816 PMCID: PMC4789118 DOI: 10.1111/jcpp.12475] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/03/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND Although attention deficit hyperactivity disorder (ADHD) is thought to reflect a continuously distributed quantitative trait, it is assessed through binary diagnosis or skewed measures biased towards its high, symptomatic extreme. A growing trend is to study the positive tail of normally distributed traits, a promising avenue, for example, to study high intelligence to increase power for gene-hunting for intelligence. However, the emergence of such a 'positive genetics' model has been tempered for ADHD due to poor phenotypic resolution at the low extreme. Overcoming this methodological limitation, we conduct the first study to assess the aetiologies of low extreme ADHD traits. METHODS In a population-representative sample of 2,143 twins, the Strength and Weaknesses of ADHD Symptoms and Normal behaviour (SWAN) questionnaire was used to assess ADHD traits on a continuum from low to high. Aetiological influences on extreme ADHD traits were estimated using DeFries-Fulker extremes analysis. ADHD traits were related to behavioural, cognitive and home environmental outcomes using regression. RESULTS Low extreme ADHD traits were significantly influenced by shared environmental factors (23-35%) but were not significantly heritable. In contrast, high-extreme ADHD traits showed significant heritability (39-51%) but no shared environmental influences. Compared to individuals with high extreme or with average levels of ADHD traits, individuals with low extreme ADHD traits showed fewer internalizing and externalizing behaviour problems, better cognitive performance and more positive behaviours and positive home environmental outcomes. CONCLUSIONS Shared environmental influences on low extreme ADHD traits may reflect passive gene-environment correlation, which arises because parents provide environments as well as passing on genes. Studying the low extreme opens new avenues to study mechanisms underlying previously neglected positive behaviours. This is different from the current deficit-based model of intervention, but congruent with a population-level approach to improving youth wellbeing.
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Affiliation(s)
- Corina U. Greven
- Department of Cognitive NeuroscienceDonders Institute for BrainCognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands,Karakter Child and Adolescent Psychiatry University CenterNijmegenThe Netherlands,Medical Research Council Social, Genetic & Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceKing's College LondonLondonUK
| | - Andrew Merwood
- Medical Research Council Social, Genetic & Developmental Psychiatry CentreInstitute of Psychiatry, Psychology & NeuroscienceKing's College LondonLondonUK,Department of PsychologyUniversity of BathBathUK
| | - Jolanda M. J. van der Meer
- Department of Cognitive NeuroscienceDonders Institute for BrainCognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands,Karakter Child and Adolescent Psychiatry University CenterNijmegenThe Netherlands
| | - Claire M. A. Haworth
- School of Experimental Psychology and School of Social and Community MedicineMRC Integrative Epidemiology Unit at the University of BristolCoventryUK
| | - Nanda Rommelse
- Karakter Child and Adolescent Psychiatry University CenterNijmegenThe Netherlands,Department of PsychiatryDonders Institute for BrainCognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands
| | - Jan K. Buitelaar
- Department of Cognitive NeuroscienceDonders Institute for BrainCognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands,Karakter Child and Adolescent Psychiatry University CenterNijmegenThe Netherlands
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27
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Visser JC, Rommelse NNJ, Greven CU, Buitelaar JK. Autism spectrum disorder and attention-deficit/hyperactivity disorder in early childhood: A review of unique and shared characteristics and developmental antecedents. Neurosci Biobehav Rev 2016; 65:229-63. [PMID: 27026637 DOI: 10.1016/j.neubiorev.2016.03.019] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 03/06/2016] [Accepted: 03/08/2016] [Indexed: 12/31/2022]
Abstract
Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) have overlapping characteristics and etiological factors, but to which extent this applies to infant- and preschool age is less well understood. Comparing the pathways to ASD and ADHD from the earliest possible stages is crucial for understanding how phenotypic overlap emerges and develops. Ultimately, these insights may guide preventative and therapeutic interventions. Here, we review the literature on the core symptoms, temperament and executive function in ASD and ADHD from infancy through preschool age, and draw several conclusions: (1) the co-occurrence of ASD and ADHD increases with age, severity of symptoms and lower IQ, (2) attention problems form a linking pin between early ASD and ADHD, but the behavioral, cognitive and sensory correlates of these attention problems partly diverge between the two conditions, (3) ASD and ADHD share high levels of negative affect, although the underlying motivational and behavioral tendencies seem to differ, and (4) ASD and ADHD share difficulties with control and shifting, but partly opposite behaviors seem to be involved.
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Affiliation(s)
- Janne C Visser
- Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands.
| | - Nanda N J Rommelse
- Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands; Radboud University Medical Center, Donders Institute for Brain, Cognition and Behavior, Department of Psychiatry, Nijmegen, The Netherlands
| | - Corina U Greven
- Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands; Radboud University Medical Center, Donders Institute for Brain, Cognition and Behavior, Department of Cognitive Neuroscience, Nijmegen, The Netherlands; King's College London, Medical Research Council Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Jan K Buitelaar
- Karakter Child and Adolescent Psychiatry University Center, Nijmegen, The Netherlands; Radboud University Medical Center, Donders Institute for Brain, Cognition and Behavior, Department of Cognitive Neuroscience, Nijmegen, The Netherlands
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28
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Polner B, Aichert D, Macare C, Costa A, Ettinger U. Gently restless: association of ADHD-like traits with response inhibition and interference control. Eur Arch Psychiatry Clin Neurosci 2015; 265:689-99. [PMID: 25209569 DOI: 10.1007/s00406-014-0531-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 09/02/2014] [Indexed: 12/30/2022]
Abstract
Impairment of inhibition-related functions is one of the most pronounced cognitive deficits found in attention-deficit/hyperactivity disorder (ADHD). Compelling evidence from studies of unaffected relatives of patients with ADHD and of ADHD-like traits in healthy subjects suggest the continuous distribution of ADHD symptoms in the population. A more subtle inhibitory deficit can also be found in healthy relatives of patients and in subjects with high ADHD-like traits. Here, we examined the relationship between inhibitory performance and ADHD-like traits, for the first time, in a large sample of healthy adults by applying multiple, widely used tests of inhibition-related functions. ADHD-like traits, in general, were independently predicted by Stroop interference score and, at trend level, by go/no-go commission error rate while controlling for socio-demographic factors, verbal intelligence and neuroticism. Additionally, higher inattentive traits were related to worse Stroop performance at trend level, and higher hyperactive/impulsive traits were significantly associated with more go/no-go commission errors. ADHD-like traits were strongly related to neuroticism. The study shows that individual differences in ADHD-like traits are related to variance in fundamental inhibition-related functions over and above effects of negative affect regulation, but the relationships tend to be small. The results suggest the quasi-dimensionality of ADHD and raise further questions about the relationship between genetic factors and the deficit of inhibition-related functions in the ADHD spectrum.
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Affiliation(s)
- Bertalan Polner
- Department of Psychology, University of Bonn, Kaiser-Karl-Ring 9, 53111, Bonn, Germany.,Department of Cognitive Science, Budapest University of Technology and Economics, Budapest, Hungary
| | - Désirée Aichert
- Department of Psychiatry, University of Munich, Munich, Germany
| | | | - Anna Costa
- Department of Psychiatry, University of Munich, Munich, Germany
| | - Ulrich Ettinger
- Department of Psychology, University of Bonn, Kaiser-Karl-Ring 9, 53111, Bonn, Germany.
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29
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Familial influences on the full range of variability in attention and activity levels during adolescence: A longitudinal twin study. Dev Psychopathol 2015; 28:517-26. [PMID: 26612434 DOI: 10.1017/s0954579415001091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
To investigate familial influences on the full range of variability in attention and activity across adolescence, we collected maternal ratings of 339 twin pairs at ages 12, 14, and 16, and estimated the transmitted and new familial influences on attention and activity as measured by the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Disorder Symptoms and Normal Behavior Scale. Familial influences were substantial for both traits across adolescence: genetic influences accounted for 54%-73% (attention) and 31%-73% (activity) of the total variance, and shared environmental influences accounted for 0%-22% of the attention variance and 13%-57% of the activity variance. The longitudinal stability of individual differences in attention and activity was largely accounted for by familial influences transmitted from previous ages. Innovations over adolescence were also partially attributable to familial influences. Studying the full range of variability in attention and activity may facilitate our understanding of attention-deficit/hyperactivity disorder's etiology and intervention.
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30
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Klein M, van der Voet M, Harich B, van Hulzen KJ, Onnink AM, Hoogman M, Guadalupe T, Zwiers M, Groothuismink JM, Verberkt A, Nijhof B, Castells-Nobau A, Faraone SV, Buitelaar JK, Schenck A, Arias-Vasquez A, Franke B. Converging evidence does not support GIT1 as an ADHD risk gene. Am J Med Genet B Neuropsychiatr Genet 2015; 168:492-507. [PMID: 26061966 PMCID: PMC7164571 DOI: 10.1002/ajmg.b.32327] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/20/2015] [Indexed: 01/03/2023]
Abstract
Attention-Deficit/Hyperactivity Disorder (ADHD) is a common neuropsychiatric disorder with a complex genetic background. The G protein-coupled receptor kinase interacting ArfGAP 1 (GIT1) gene was previously associated with ADHD. We aimed at replicating the association of GIT1 with ADHD and investigated its role in cognitive and brain phenotypes. Gene-wide and single variant association analyses for GIT1 were performed for three cohorts: (1) the ADHD meta-analysis data set of the Psychiatric Genomics Consortium (PGC, N = 19,210), (2) the Dutch cohort of the International Multicentre persistent ADHD CollaboraTion (IMpACT-NL, N = 225), and (3) the Brain Imaging Genetics cohort (BIG, N = 1,300). Furthermore, functionality of the rs550818 variant as an expression quantitative trait locus (eQTL) for GIT1 was assessed in human blood samples. By using Drosophila melanogaster as a biological model system, we manipulated Git expression according to the outcome of the expression result and studied the effect of Git knockdown on neuronal morphology and locomotor activity. Association of rs550818 with ADHD was not confirmed, nor did a combination of variants in GIT1 show association with ADHD or any related measures in either of the investigated cohorts. However, the rs550818 risk-genotype did reduce GIT1 expression level. Git knockdown in Drosophila caused abnormal synapse and dendrite morphology, but did not affect locomotor activity. In summary, we could not confirm GIT1 as an ADHD candidate gene, while rs550818 was found to be an eQTL for GIT1. Despite GIT1's regulation of neuronal morphology, alterations in gene expression do not appear to have ADHD-related behavioral consequences. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- M Klein
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - M van der Voet
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - B Harich
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - KJ van Hulzen
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - AM Onnink
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands,Department of Psychiatry, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, The Netherlands
| | - M Hoogman
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - T Guadalupe
- Department of Language and Genetics, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands,International Max Planck Research School for Language Sciences, Nijmegen, The Netherlands
| | - M Zwiers
- Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - JM Groothuismink
- Department of Human Genetics, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
| | - A Verberkt
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - B Nijhof
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - A Castells-Nobau
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - SV Faraone
- Department of Psychiatry, State University of New York (SUNY) Upstate Medical University, Syracuse, New York,Department of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York
| | - JK Buitelaar
- Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - A Schenck
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - A Arias-Vasquez
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands,Department of Psychiatry, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, The Netherlands,Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - B Franke
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands,Department of Psychiatry, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, The Netherlands
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Brikell I, Kuja-Halkola R, Larsson H. Heritability of attention-deficit hyperactivity disorder in adults. Am J Med Genet B Neuropsychiatr Genet 2015; 168:406-413. [PMID: 26129777 DOI: 10.1002/ajmg.b.32335] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 06/15/2015] [Indexed: 11/07/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder. Symptoms often persist into adulthood, with a prevalence of 2.5-5% in adult populations. Twin studies in childhood consistently report high heritabilities of 70-80%, while studies in adult samples show only moderate heritability of 30-40% when estimated from self-ratings. This review summarizes the available research on the heritability of ADHD in adults. Three key findings are outlined: (i) self-ratings lead to relatively low heritability estimates of ADHD, independent of age and whether ratings refer to current or retrospective symptoms; (ii) studies relying on different informants to rate each twin within a pair (i.e., self-ratings and different parents/teachers rating each twin in a pair) consistently yield lower heritability estimates than studies relying on ratings from a single informant; (iii) studies using cross-informant data via either combined parent and self-ratings or clinical diagnoses information suggest that the heritability of ADHD in adults could be as high as 70-80%. Together, the reviewed studies suggest that the previously reported low heritability of ADHD in adults is unlikely to reflect a true developmental change. Instead, the drop in heritability is better explained by rater effects related to a switch from using one rater for both twins in a pair (parent/teacher) in childhood, to relying on self-ratings (where each twin rates themselves) of ADHD symptoms in adulthood. When rater effects are addressed using cross-informant approaches, the heritability of ADHD in adults appears to be comparable to the heritability of ADHD in childhood. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Isabell Brikell
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Ralf Kuja-Halkola
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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32
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Pingault JB, Viding E, Galéra C, Greven CU, Zheng Y, Plomin R, Rijsdijk F. Genetic and Environmental Influences on the Developmental Course of Attention-Deficit/Hyperactivity Disorder Symptoms From Childhood to Adolescence. JAMA Psychiatry 2015; 72:651-8. [PMID: 25945901 PMCID: PMC6328013 DOI: 10.1001/jamapsychiatry.2015.0469] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
IMPORTANCE Attention-deficit/hyperactivity disorder (ADHD) is conceptualized as a neurodevelopmental disorder that is strongly heritable. However, to our knowledge, no study to date has examined the genetic and environmental influences explaining interindividual differences in the developmental course of ADHD symptoms from childhood to adolescence (ie, systematic decreases or increases with age). The reason ADHD symptoms persist in some children but decline in others is an important concern, with implications for prognosis and interventions. OBJECTIVE To assess the proportional impact of genes and the environment on interindividual differences in the developmental course of ADHD symptom domains of hyperactivity/impulsivity and inattention between ages 8 and 16 years. DESIGN, SETTING, AND PARTICIPANTS A prospective sample of 8395 twin pairs from the Twins Early Development Study, recruited from population records of births in England and Wales between January 1, 1994, and December 31, 1996. Data collection at age 8 years took place between November 2002 and November 2004; data collection at age 16 years took place between February 2011 and January 2013. MAIN OUTCOMES AND MEASURES Both DSM-IV ADHD symptom subscales were rated 4 times by participants' mothers. RESULTS Estimates from latent growth curve models indicated that the developmental course of hyperactivity/impulsivity symptoms followed a sharp linear decrease (mean score of 6.0 at age 8 years to 2.9 at age 16 years). Interindividual differences in the linear change in hyperactivity/impulsivity were under strong additive genetic influences (81%; 95% CI, 73%-88%). More than half of the genetic variation was specific to the developmental course and not shared with the baseline level of hyperactivity/impulsivity. The linear decrease in inattention symptoms was less pronounced (mean score of 5.8 at age 8 years to 4.9 at age 16 years). Nonadditive genetic influences accounted for a substantial amount of variation in the developmental course of inattention symptoms (54%; 95% CI, 8%-76%), with more than half being specific to the developmental course. CONCLUSIONS AND RELEVANCE The large genetic influences on the developmental course of ADHD symptoms are mostly specific and independent of those that account for variation in the baseline level of symptoms. Different sets of genes may be associated with the developmental course vs the baseline level of ADHD symptoms and explain why some children remit from ADHD, whereas others persist. Recent longitudinal imaging data indicate that the maintenance or increase in symptoms is underpinned by atypical trajectories of cortical development. This may reflect a specific genetic liability, distinct from that which contributes to baseline ADHD symptoms, and warrants closer follow-up.
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Affiliation(s)
- Jean-Baptiste Pingault
- Department of Psychology, Division of Psychology and Language Sciences, University College London, London, England2MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, England
| | - Essi Viding
- Department of Psychology, Division of Psychology and Language Sciences, University College London, London, England2MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, England
| | - Cédric Galéra
- Department of Child and Adolescent Psychiatry, Charles Perrens Hospital and INSERM, The Bordeaux School of Public Health (Institut de Santé Publique, d’Epidémiologie et de Développement), Centre INSERM U897, Epidemiology-Biostatistics, University of Borde
| | - Corina U. Greven
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, England4Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijme
| | - Yao Zheng
- Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Robert Plomin
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, England
| | - Frühling Rijsdijk
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, England
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Dela Peña I, Bang M, Lee J, de la Peña JB, Kim BN, Han DH, Noh M, Shin CY, Cheong JH. Common prefrontal cortical gene expression profiles between adolescent SHR/NCrl and WKY/NCrl rats which showed inattention behavior. Behav Brain Res 2015; 291:268-276. [PMID: 26048425 DOI: 10.1016/j.bbr.2015.05.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/07/2015] [Accepted: 05/10/2015] [Indexed: 12/12/2022]
Abstract
Factor analyses of attention-deficit/hyperactivity (ADHD) symptoms divide the behavioral symptoms of ADHD into two separate domains, one reflecting inattention and the other, a combination of hyperactivity and impulsivity. Identifying domain-specific genetic risk variants may aid in the discovery of specific biological risk factors for ADHD. In contrast with data available on genes involved in hyperactivity and impulsivity, there is limited information on the genetic influences of inattention. Transcriptional profiling analysis in animal models of disorders may provide an important tool to identify genetic involvement in behavioral phenotypes. To explore some of the potential genetic underpinnings of ADHD inattention, we examined common differentially expressed genes (DEGs) in the prefrontal cortex of SHR/NCrl, the most validated animal model of ADHD and WKY/NCrl, animal model of ADHD-inattentive type. In contrast with Wistar rats, strain representing the "normal" heterogeneous population, SHR/NCrl and WKY/NCrl showed inattention behavior in the Y-maze task. The common DEGs in the PFC of SHR/NCrl and WKY/NCrl vs. Wistar rats are those involved in transcription (e.g. Creg1, Thrsp, Zeb2), synaptic transmission (e.g. Atp2b2, Syt12, Chrna5), neurological system process (e.g. Atg7, Cacnb4, Grin3a), and immune response (e.g. Atg7, Ip6k2, Mx2). qRT-PCR analyses validated expression patterns of genes representing the major functional gene families among the DEGs (Grin3a, Thrsp, Vof-16 and Zeb2). Although further studies are warranted, the present findings indicate novel genes associated with known functional pathways of relevance to ADHD which are assumed to play important roles in the etiology of ADHD-inattentive subtype.
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Affiliation(s)
- Ike Dela Peña
- Uimyung Research Institute for Neuroscience, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815, Nowon-gu, Seoul 139-742, Republic of Korea; Department of Pharmaceutical and Administrative Sciences, Loma Linda University, CA 92350, USA.
| | - Minji Bang
- Department of Neuroscience, School of Medicine, Konkuk University, Seoul 143-701, Republic of Korea
| | - Jinhee Lee
- Department of Neuroscience, School of Medicine, Konkuk University, Seoul 143-701, Republic of Korea
| | - June Bryan de la Peña
- Uimyung Research Institute for Neuroscience, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815, Nowon-gu, Seoul 139-742, Republic of Korea
| | - Bung-Nyun Kim
- Division of Child and Adolescent Psychiatry, Clinical Research Institute, Seoul National University Hospital, 28 Yungundong, Chongrogu, Seoul 110-744, Republic of Korea
| | - Doug Hyun Han
- Department of Psychiatry, Chung-Ang University Medical School, 102 Heukseok-ro, Dongjak-gu, Seoul 156-755, Republic of Korea
| | - Minsoo Noh
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Chan Young Shin
- Department of Neuroscience, School of Medicine, Konkuk University, Seoul 143-701, Republic of Korea
| | - Jae Hoon Cheong
- Uimyung Research Institute for Neuroscience, Sahmyook University, 26-21 Kongreung-2-dong, Hwarangro-815, Nowon-gu, Seoul 139-742, Republic of Korea.
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Michelini G, Eley TC, Gregory AM, McAdams TA. Aetiological overlap between anxiety and attention deficit hyperactivity symptom dimensions in adolescence. J Child Psychol Psychiatry 2015; 56:423-31. [PMID: 25195626 PMCID: PMC6607691 DOI: 10.1111/jcpp.12318] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/17/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND Anxiety and attention-deficit/hyperactivity (ADH) problems are common in adolescence, often co-occur, and are characterised by high heterogeneity in their phenotypic expressions. Although it is known that anxiety and ADH problems correlate, the relationships between subtypes of anxiety and ADH problems have been scarcely investigated. METHODS Using a large population sample of adolescent twins and siblings we explored the phenotypic and aetiological association between anxiety subtypes (panic/agoraphobia, separation anxiety, social anxiety, physical injury fears, obsessive-compulsive symptoms and generalised anxiety) and the two ADH dimensions (attention problems and hyperactivity/impulsivity). Both phenotypes were assessed using self-report questionnaires. RESULTS The association between ADH problems and anxiety could be entirely attributed to attention problems, not hyperactivity/impulsivity. Most of the correlations between anxiety subtypes and attention problems showed an approximately equal role of genetic and nonshared environmental factors. CONCLUSIONS The high heterogeneity within anxiety and ADH problems should be taken into account in order to better understand comorbidity between them.
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Affiliation(s)
- Giorgia Michelini
- MRC SocialGenetic and Developmental Psychiatry CentreInstitute of PsychiatryKing's College LondonLondonUK
| | - Thalia C. Eley
- MRC SocialGenetic and Developmental Psychiatry CentreInstitute of PsychiatryKing's College LondonLondonUK
| | | | - Tom A. McAdams
- MRC SocialGenetic and Developmental Psychiatry CentreInstitute of PsychiatryKing's College LondonLondonUK
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Salatino-Oliveira A, Genro JP, Polanczyk G, Zeni C, Schmitz M, Kieling C, Anselmi L, Menezes AMB, Barros FC, Polina ER, Mota NR, Grevet EH, Bau CHD, Rohde LA, Hutz MH. Cadherin-13 gene is associated with hyperactive/impulsive symptoms in attention/deficit hyperactivity disorder. Am J Med Genet B Neuropsychiatr Genet 2015; 168B:162-9. [PMID: 25739828 DOI: 10.1002/ajmg.b.32293] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 12/10/2014] [Indexed: 12/19/2022]
Abstract
Several efforts have been made to find new genetic risk variants which explain the high heritability of ADHD. At the genome level, genes involved in neurodevelopmental pathways were pointed as candidates. CDH13 and CTNNA2 genes are within GWAS top hits in ADHD and there are emerging notions about their contribution to ADHD pathophysiology. The main goal of this study is to test the association between SNPs in CDH13 and CTNNA2 genes and ADHD across the life cycle in subjects with ADHD. This study included 1,136 unrelated ADHD cases and 946 individuals without ADHD. No significant association between CDH13 and CTNNA2 was observed between cases and controls across different samples (P ≥ 0.096 for all comparisons). No allele was significantly more transmitted than expected from parents to ADHD probands. The CDH13 rs11150556 CC genotype was associated with more hyperactive/impulsive symptoms in youths with ADHD (children/adolescents clinical sample: F = 7.666, P = 0.006, FDR P-value = 0.032; Pelotas Birth Cohort sample: F = 6.711, P = 0.011, FDR P-value = 0.032). Although there are many open questions regarding the role of neurodevelopmental genes in ADHD symptoms, the present study suggests that CDH13 is associated with hyperactive/impulsive symptoms in youths with ADHD.
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Taylor MJ, Charman T, Ronald A. Where are the strongest associations between autistic traits and traits of ADHD? evidence from a community-based twin study. Eur Child Adolesc Psychiatry 2015; 24:1129-38. [PMID: 25600178 PMCID: PMC4554745 DOI: 10.1007/s00787-014-0666-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 12/13/2014] [Indexed: 11/24/2022]
Abstract
Autism spectrum conditions (ASC) and attention-deficit/hyperactivity disorder (ADHD) regularly co-occur. Twin studies increasingly indicate that these conditions may have overlapping genetic causes. Less is known about the degree to which specific autistic traits relate to specific behaviours characteristic of ADHD. We hence tested, using the classical twin design, whether specific dimensional autistic traits, including social difficulties, communication atypicalities and repetitive behaviours, would display differential degrees of aetiological overlap with specific traits of ADHD, including hyperactivity/impulsivity and inattention. Parents of approximately 4,000 pairs of 12-year-old twins completed the Childhood Autism Spectrum Test and Conners' Parent Rating Scale. These measures were divided into subscales corresponding to different types of autistic and ADHD behaviours. Twin model fitting suggested that the degree of genetic overlap was particularly strong between communication difficulties and traits of ADHD (genetic correlations = .47-.51), while repetitive behaviours and social difficulties showed moderate (genetic correlations = .12-.33) and modest (.05-.11) genetic overlap respectively. Environmental overlap was low across all subscales (correlations = .01-.23). These patterns were also apparent at the extremes of the general population, with communication difficulties showing the highest genetic overlap with traits of ADHD. These findings indicate that molecular genetic studies seeking to uncover the shared genetic basis of ASC and ADHD would benefit from taking a symptom-specific approach. Furthermore, they could also help to explain why studies of the communication abilities of individuals with ASC and ADHD have produced overlapping findings.
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Affiliation(s)
- Mark J. Taylor
- />Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK
| | - Tony Charman
- />Department of Psychology, King’s College London, London, UK
| | - Angelica Ronald
- />Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK
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Abstract
Attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) often co-occur. Factor analyses of ASD traits in children with and without ASD indicate the presence of social and restrictive–repetitive behaviour (RRB) factors. This study used exploratory factor analyses to determine the structure of ASD traits (assessed using the Social Communication Questionnaire) in children with ADHD. Distinct factors were observed for ‘social’ and ‘rigidity’ traits, corresponding to previous factor analyses in clinical ASD and population samples. This indicates that the split between social-communicative and RRB dimensions is unaffected by ADHD in children. Moreover, the study also finds that there is some overlap across hyperactive-impulsive symptoms and RRB traits in children with ADHD, which merits further investigation.
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LoParo D, Waldman I. Twins' rearing environment similarity and childhood externalizing disorders: a test of the equal environments assumption. Behav Genet 2014; 44:606-13. [PMID: 25326879 DOI: 10.1007/s10519-014-9685-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 10/01/2014] [Indexed: 11/28/2022]
Abstract
The equal environments assumption (EEA) of the twin method posits that environmental influences that are etiologically relevant to a given phenotype are no more likely to be shared by monozygotic (MZ) than dizygotic (DZ) twin pairs. One method of testing the EEA is to evaluate whether increased rearing environment similarity in MZ twin pairs compared to DZ twin pairs is related to increased phenotypic correlation. In a sample of 885 twin pairs, we contrasted similarity in rearing environment between MZ and DZ twin pairs, examined the correlation between similarity in rearing environment and conduct disorder (CD), oppositional-defiant disorder (ODD), inattention, and hyperactivity-impulsivity symptom dimensions, and tested the effects of differential similarity in rearing environments between MZ and DZ twin pairs by testing whether rearing environment similarity moderated the correlations for the externalizing symptom dimensions. We found that MZ twins experienced substantially more similar rearing environments than DZ twins, but that there was little evidence that MZ and DZ correlations for the externalizing symptom dimensions varied by rearing environment similarity. Thus, these results constitute evidence for the validity of the EEA for childhood externalizing disorders.
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Affiliation(s)
- Devon LoParo
- Psychology Department, Emory University, 36 Eagle Row, Atlanta, GA, 30306, USA,
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Polderman TJC, Hoekstra RA, Posthuma D, Larsson H. The co-occurrence of autistic and ADHD dimensions in adults: an etiological study in 17,770 twins. Transl Psychiatry 2014; 4:e435. [PMID: 25180574 PMCID: PMC4203013 DOI: 10.1038/tp.2014.84] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 07/26/2014] [Indexed: 12/27/2022] Open
Abstract
Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) often occur together. To obtain more insight in potential causes for the co-occurrence, this study examined the genetic and environmental etiology of the association between specific ASD and ADHD disorder dimensions. Self-reported data on ASD dimensions social and communication difficulties (ASDsc), and repetitive and restricted behavior and interests (ASDr), and ADHD dimensions inattention (IA), and hyperactivity/impulsivity (HI) were assessed in a community sample of 17,770 adult Swedish twins. Phenotypic, genetic and environmental associations between disorder dimensions were examined in a multivariate model, accounting for sex differences. ASDr showed the strongest associations with IA and HI in both sexes (r(p) 0.33 to 0.40). ASDsc also correlated moderately with IA (females r(p) 0.29 and males r(p) 0.35) but only modestly with HI (females r(p) 0.17 and males r(p) 0.20). Genetic correlations ranged from 0.22 to 0.64 and were strongest between ASDr and IA and HI. Sex differences were virtually absent. The ASDr dimension (reflecting restricted, repetitive and stereotyped patterns of behavior, interests and activities) showed the strongest association with dimensions of ADHD, on a phenotypic, genetic and environmental level. This study opens new avenues for molecular genetic research. As our findings demonstrated that genetic overlap between disorders is dimension-specific, future gene-finding studies on psychiatric comorbidity should focus on carefully selected genetically related dimensions of disorders.
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Affiliation(s)
- T J C Polderman
- Department of Functional Genomics, Complex Trait Genetics, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, The Netherlands
| | - R A Hoekstra
- Department of Life, Health and Chemical Sciences, Faculty of Science, The Open University, Milton Keynes, UK
| | - D Posthuma
- Department of Functional Genomics, Complex Trait Genetics, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, The Netherlands
- Department of Complex Trait Genetics, Clinical Genetics, VU Medical Center, Amsterdam, The Netherlands
| | - H Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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Cheung CHM, Fazier-Wood AC, Asherson P, Rijsdijk F, Kuntsi J. Shared cognitive impairments and aetiology in ADHD symptoms and reading difficulties. PLoS One 2014; 9:e98590. [PMID: 24886915 PMCID: PMC4041781 DOI: 10.1371/journal.pone.0098590] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 05/05/2014] [Indexed: 12/31/2022] Open
Abstract
Background Twin studies indicate that the frequent co-occurrence of attention deficit hyperactivity disorder (ADHD) symptoms and reading difficulties (RD) is largely due to shared genetic influences. Both disorders are associated with multiple cognitive impairments, but it remains unclear which cognitive impairments share the aetiological pathway, underlying the co-occurrence of the symptoms. We address this question using a sample of twins aged 7–10 and a range of cognitive measures previously associated with ADHD symptoms or RD. Methods We performed multivariate structural equation modelling analyses on parent and teacher ratings on the ADHD symptom domains of inattention and hyperactivity, parent ratings on RD, and cognitive data on response inhibition (commission errors, CE), reaction time variability (RTV), verbal short-term memory (STM), working memory (WM) and choice impulsivity, from a population sample of 1312 twins aged 7–10 years. Results Three cognitive processes showed significant phenotypic and genetic associations with both inattention symptoms and RD: RTV, verbal WM and STM. While STM captured only 11% of the shared genetic risk between inattention and RD, the estimates increased somewhat for WM (21%) and RTV (28%); yet most of the genetic sharing between inattention and RD remained unaccounted for in each case. Conclusion While response inhibition and choice impulsivity did not emerge as important cognitive processes underlying the co-occurrence between ADHD symptoms and RD, RTV and verbal memory processes separately showed significant phenotypic and genetic associations with both inattention symptoms and RD. Future studies employing longitudinal designs will be required to investigate the developmental pathways and direction of causality further.
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Affiliation(s)
- Celeste H. M. Cheung
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Alexis C. Fazier-Wood
- Human Genetics Center, Division of Epidemiology, Human Genetics and Environmental Science, School of Public Health, University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - Philip Asherson
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Fruhling Rijsdijk
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
| | - Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom
- * E-mail:
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Kuntsi J, Pinto R, Price TS, van der Meere JJ, Frazier-Wood AC, Asherson P. The separation of ADHD inattention and hyperactivity-impulsivity symptoms: pathways from genetic effects to cognitive impairments and symptoms. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 2014; 42:127-36. [PMID: 23839718 PMCID: PMC4520068 DOI: 10.1007/s10802-013-9771-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Both shared and unique genetic risk factors underlie the two symptom domains of attention deficit hyperactivity disorder (ADHD): inattention and hyperactivity-impulsivity. The developmental course and relationship to co-occurring disorders differs across the two symptom domains, highlighting the importance of their partially distinct etiologies. Familial cognitive impairment factors have been identified in ADHD, but whether they show specificity in relation to the two ADHD symptom domains remains poorly understood. We aimed to investigate whether different cognitive impairments are genetically linked to the ADHD symptom domains of inattention versus hyperactivity-impulsivity. We conducted multivariate genetic model fitting analyses on ADHD symptom scores and cognitive data, from go/no-go and fast tasks, collected on a population twin sample of 1,312 children aged 7-10. Reaction time variability (RTV) showed substantial genetic overlap with inattention, as observed in an additive genetic correlation of 0.64, compared to an additive genetic correlation of 0.31 with hyperactivity-impulsivity. Commission errors (CE) showed low additive genetic correlations with both hyperactivity-impulsivity and inattention (genetic correlations of 0.17 and 0.11, respectively). The additive genetic correlation between RTV and CE was also low and non-significant at -0.10, consistent with the etiological separation between the two indices of cognitive impairments. Overall, two key cognitive impairments phenotypically associated with ADHD symptoms, captured by RTV and CE, showed different genetic relationships to the two ADHD symptom domains. The findings extend a previous model of two familial cognitive impairment factors in combined subtype ADHD by separating pathways underlying inattention and hyperactivity-impulsivity symptoms.
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Affiliation(s)
- Jonna Kuntsi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, De Crespigny Park, London, SE5 8AF, UK,
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Greven CU, Kovas Y, Willcutt EG, Petrill SA, Plomin R. Evidence for shared genetic risk between ADHD symptoms and reduced mathematics ability: a twin study. J Child Psychol Psychiatry 2014; 55:39-48. [PMID: 23731013 PMCID: PMC3865138 DOI: 10.1111/jcpp.12090] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/15/2013] [Indexed: 01/13/2023]
Abstract
BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) symptoms and mathematics ability are associated, but little is known about the genetic and environmental influences underlying this association. METHODS Data came from more than 6,000 twelve-year-old twin pairs from the UK population-representative Twins Early Development Study. Parents rated each twin's behaviour using a DSM-IV-based 18-item questionnaire of inattentive and hyperactive-impulsive ADHD symptoms. Mathematics tests based on the UK National Curriculum were completed by each twin. The twins also completed standardised tests of reading and general cognitive ability. Multivariate twin model fitting was applied. RESULTS Inattentive and hyperactive-impulsive ADHD symptoms were highly heritable (67% and 73% respectively). Mathematics ability was moderately heritable (46%). Mathematics ability and inattentiveness showed a significantly greater phenotypic correlation (r(p) = -.26) and genetic correlation (r(A) = -.41) than mathematics ability and hyperactivity-impulsivity (r(p) = -.18; r(A) = -.22). The genetic correlation between inattentiveness and mathematics ability was largely independent from hyperactivity-impulsivity, and was only partially accounted for by genetic influences related to reading and general cognitive ability. CONCLUSIONS Results revealed the novel finding that mathematics ability shows significantly stronger phenotypic and genetic associations with inattentiveness than with hyperactivity-impulsivity. Genetic associations between inattentiveness and mathematics ability could only partially be accounted for by hyperactivity-impulsivity, reading and general cognitive ability. Results suggest that mathematics ability is associated with ADHD symptoms largely because it shares genetic risk factors with inattentiveness, and provide further evidence for considering inattentiveness and hyperactivity-impulsivity separately. DNA markers for ADHD symptoms (especially inattentiveness) may also be candidate risk factors for mathematics ability and vice versa.
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Affiliation(s)
- Corina U. Greven
- Radboud University Medical Centre Nijmegen, Donders Institute for Brain, Cognition and Behaviour, The Netherlands,King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, U.K
| | - Yulia Kovas
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, U.K.,Tomsk State University, Department of Psychology, Russia,Goldsmiths, Department of Psychology, U.K
| | - Erik G. Willcutt
- University of Colorado, Department of Psychology and Neuroscience, U.S
| | - Stephen A. Petrill
- Ohio State University, Department of Human Development and Family Science, U.S
| | - Robert Plomin
- King’s College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, U.K
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Mathias de Almeida K, Nery FG, Moreno RA, Gorenstein C, Lafer B. A sib-pair analysis of impulsivity in bipolar disorder type I. Compr Psychiatry 2013; 54:1148-52. [PMID: 23890763 DOI: 10.1016/j.comppsych.2013.05.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 05/02/2013] [Accepted: 05/06/2013] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVE The aim of this study was to compare impulsivity among patients with bipolar disorder, their siblings, and healthy controls in order to examine whether impulsivity in bipolar disorder is related to genetic liability for the illness. METHODS Using the Barratt Impulsiveness Scale, we assessed 204 subjects: 67 euthymic outpatients with bipolar disorder type I, 67 siblings without bipolar disorder, and 70 healthy controls. RESULTS Impulsivity scores were higher among patients with bipolar disorder than among healthy controls. Siblings showed higher motor impulsivity scores than did healthy controls. CONCLUSIONS Our results suggest that motor impulsivity may be a vulnerability marker for bipolar disorder. Our data may contribute to further improve preventive strategies in subjects at high risk for bipolar disorder.
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Affiliation(s)
- Karla Mathias de Almeida
- Bipolar Disorder Research Program (PROMAN), Institute of Psychiatry, University of São Paulo Medical School, São Paulo, Brazil.
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Bralten J, Franke B, Waldman I, Rommelse N, Hartman C, Asherson P, Banaschewski T, Ebstein RP, Gill M, Miranda A, Oades RD, Roeyers H, Rothenberger A, Sergeant JA, Oosterlaan J, Sonuga-Barke E, Steinhausen HC, Faraone SV, Buitelaar JK, Arias-Vásquez A. Candidate genetic pathways for attention-deficit/hyperactivity disorder (ADHD) show association to hyperactive/impulsive symptoms in children with ADHD. J Am Acad Child Adolesc Psychiatry 2013; 52:1204-1212.e1. [PMID: 24157394 DOI: 10.1016/j.jaac.2013.08.020] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 07/05/2013] [Accepted: 08/29/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Because multiple genes with small effect sizes are assumed to play a role in attention-deficit/hyperactivity disorder (ADHD) etiology, considering multiple variants within the same analysis likely increases the total explained phenotypic variance, thereby boosting the power of genetic studies. This study investigated whether pathway-based analysis could bring scientists closer to unraveling the biology of ADHD. METHOD The pathway was described as a predefined gene selection based on a well-established database or literature data. Common genetic variants in pathways involved in dopamine/norepinephrine and serotonin neurotransmission and genes involved in neuritic outgrowth were investigated in cases from the International Multicentre ADHD Genetics (IMAGE) study. Multivariable analysis was performed to combine the effects of single genetic variants within the pathway genes. Phenotypes were DSM-IV symptom counts for inattention and hyperactivity/impulsivity (n = 871) and symptom severity measured with the Conners Parent (n = 930) and Teacher (n = 916) Rating Scales. RESULTS Summing genetic effects of common genetic variants within the pathways showed a significant association with hyperactive/impulsive symptoms ((p)empirical = .007) but not with inattentive symptoms ((p)empirical = .73). Analysis of parent-rated Conners hyperactive/impulsive symptom scores validated this result ((p)empirical = .0018). Teacher-rated Conners scores were not associated. Post hoc analyses showed a significant contribution of all pathways to the hyperactive/impulsive symptom domain (dopamine/norepinephrine, (p)empirical = .0004; serotonin, (p)empirical = .0149; neuritic outgrowth, (p)empirical = .0452). CONCLUSION The present analysis shows an association between common variants in 3 genetic pathways and the hyperactive/impulsive component of ADHD. This study demonstrates that pathway-based association analyses, using quantitative measurements of ADHD symptom domains, can increase the power of genetic analyses to identify biological risk factors involved in this disorder.
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Affiliation(s)
- Janita Bralten
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
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O'Nions E, Viding E, Greven CU, Ronald A, Happé F. Pathological demand avoidance: exploring the behavioural profile. AUTISM : THE INTERNATIONAL JOURNAL OF RESEARCH AND PRACTICE 2013; 18:538-44. [PMID: 24104509 DOI: 10.1177/1362361313481861] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
'Pathological Demand Avoidance' is a term increasingly used by practitioners in the United Kingdom. It was coined to describe a profile of obsessive resistance to everyday demands and requests, with a tendency to resort to 'socially manipulative' behaviour, including outrageous or embarrassing acts. Pathological demand avoidance is thought to share aspects of social impairment with autism spectrum disorders, but autism spectrum disorder-appropriate strategies, such as routine and repetition, are described as unhelpful. Outrageous acts and lack of concern for their effects draw parallels with conduct problems and callous-unemotional traits. However, reward-based techniques, effective with conduct problems and callous-unemotional traits, seem not to work in pathological demand avoidance. Despite increasing interest and controversy over the pathological demand avoidance label, there is only one published study to date. We present the first systematic comparison of the behavioural profile of children receiving the term pathological demand avoidance (N = 25) to children with autism spectrum disorders (N = 39) or conduct problems and callous-unemotional traits (N = 28), using parent-report indices of psychopathology. The pathological demand avoidance group displayed comparable levels of autistic traits and peer problems to the autism spectrum disorders group and anti-social traits approaching those seen in the conduct problems and callous-unemotional traits group. Emotional symptoms in pathological demand avoidance exceeded both comparison groups. Findings highlight the extreme behavioural impairment associated with pathological demand avoidance and the need to explore whether behavioural overlap reflects a similar neurocognitive basis to existing groups.
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Affiliation(s)
| | - Essi Viding
- King's College London, UK University College London, UK
| | - Corina U Greven
- King's College London, UK Radboud University Nijmegen Medical Centre, The Netherlands
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Harold GT, Leve LD, Barrett D, Elam K, Neiderhiser JM, Natsuaki MN, Shaw DS, Reiss D, Thapar A. Biological and rearing mother influences on child ADHD symptoms: revisiting the developmental interface between nature and nurture. J Child Psychol Psychiatry 2013; 54:1038-46. [PMID: 24007415 PMCID: PMC3767192 DOI: 10.1111/jcpp.12100] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/02/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children's ADHD symptoms, and the role of children's ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and nonbiologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area. METHODS A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5-8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports). RESULTS Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically related maternal ADHD symptoms to biologically unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms. CONCLUSIONS Results highlight the importance of genetically influenced child ADHD-related temperamental attributes on genetically unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed.
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Trzaskowski M, Dale PS, Plomin R. No genetic influence for childhood behavior problems from DNA analysis. J Am Acad Child Adolesc Psychiatry 2013; 52:1048-1056.e3. [PMID: 24074471 PMCID: PMC3914760 DOI: 10.1016/j.jaac.2013.07.016] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/30/2013] [Accepted: 07/31/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Twin studies of behavior problems in childhood point to substantial genetic influence. It is now possible to estimate genetic influence using DNA alone in samples of unrelated individuals, not relying on family-based designs such as twins. A linear mixed model, which incorporates DNA microarray data, has confirmed twin results by showing substantial genetic influence for diverse traits in adults. Here we present direct comparisons between twin and DNA heritability estimates for childhood behavior problems as rated by parents, teachers, and children themselves. METHOD Behavior problem data from 2,500 UK-representative 12-year-old twin pairs were used in twin analyses; DNA analyses were based on 1 member of the twin pair with genotype data for 1.7 million DNA markers. Diverse behavior problems were assessed, including autistic, depressive, and hyperactive symptoms. Genetic influence from DNA was estimated using genome-wide complex trait analysis (GCTA), and the twin estimates of heritability were based on standard twin model fitting. RESULTS Behavior problems in childhood-whether rated by parents, teachers, or children themselves-show no significant genetic influence using GCTA, even though twin study estimates of heritability are substantial in the same sample, and even though both GCTA and twin study estimates of genetic influence are substantial for cognitive and anthropometric traits. CONCLUSIONS We suggest that this new type of "missing heritability," that is, the gap between GCTA and twin study estimates for behavior problems in childhood, is due to nonadditive genetic influence, which will make it more difficult to identify genes responsible for heritability.
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Affiliation(s)
- Maciej Trzaskowski
- Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London.
| | | | - Robert Plomin
- Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London
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Merwood A, Greven CU, Price TS, Rijsdijk F, Kuntsi J, McLoughlin G, Larsson H, Asherson PJ. Different heritabilities but shared etiological influences for parent, teacher and self-ratings of ADHD symptoms: an adolescent twin study. Psychol Med 2013; 43:1973-1984. [PMID: 23298428 PMCID: PMC3818571 DOI: 10.1017/s0033291712002978] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Parent and teacher ratings of attention deficit hyperactivity disorder (ADHD) symptoms yield high estimates of heritability whereas self-ratings typically yield lower estimates. To understand why, the present study examined the etiological overlap between parent, teacher and self-ratings of ADHD symptoms in a population-based sample of 11-12-year-old twins. Method Participants were from the Twins Early Development Study (TEDS). ADHD symptoms were assessed using the Strengths and Difficulties Questionnaire (SDQ) hyperactivity scale completed by parents, teachers and children. Structural equation modeling was used to examine genetic and environmental contributions to phenotypic variance/covariance. RESULTS The broad-sense heritability of ADHD symptoms was 82% for parent ratings, 60% for teacher ratings and 48% for self-ratings. Post-hoc analyses revealed significantly higher heritability for same-teacher than different-teacher ratings of ADHD (76% v. 49%). A common pathway model best explained the relationship between different informant ratings, with common genetic influences accounting for 84% of the covariance between parent, teacher and self-rated ADHD symptoms. The remaining variance was explained by rater-specific genetic and non-shared environmental influences. CONCLUSIONS Despite different heritabilities, there were shared genetic influences for parent, teacher and self-ratings of ADHD symptoms, indicating that different informants rated some of the same aspects of behavior. The low heritability estimated for self-ratings and different-teacher ratings may reflect increased measurement error when different informants rate each twin from a pair, and/or greater non-shared environmental influences. Future studies into the genetic influences on ADHD should incorporate informant data in addition to self-ratings to capture a pervasive, heritable component of ADHD symptomatology.
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Affiliation(s)
- A Merwood
- King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, London, UK.
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What have we learned from recent twin studies about the etiology of neurodevelopmental disorders? Curr Opin Neurol 2013; 26:111-21. [PMID: 23426380 DOI: 10.1097/wco.0b013e32835f19c3] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE OF REVIEW The relative influence of genes and environment on the liability to neurodevelopmental disorders (NDDs) can be investigated using a twin design. This review highlights the results of the most recent twin studies of NDDs. RECENT FINDINGS Recent twin studies have confirmed that NDDs show moderate-to-high heritability, and that from an etiological viewpoint both autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are best regarded as the extremes on a continuous liability distribution. Both ASD and ADHD show high heritability in childhood and a substantial drop in heritability in adulthood, which is likely explained by the use of different assessment strategies in childhood versus adulthood, or by a complex mechanism of gene-by-environment interaction. NDDs show substantial comorbidity among each other, and with other mental health problems, which is partly because of a shared genetic etiology between different disorders. SUMMARY The findings of twin studies implicate substantial heritability of NDDs, and warrant large-scale molecular genetic studies for such traits.
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Merwood A, Asherson P, Larsson H. Genetic associations between the ADHD symptom dimensions and Cloninger's temperament dimensions in adult twins. Eur Neuropsychopharmacol 2013; 23:416-25. [PMID: 23122641 DOI: 10.1016/j.euroneuro.2012.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 09/05/2012] [Accepted: 10/05/2012] [Indexed: 10/27/2022]
Abstract
Previous studies have identified phenotypic associations between Cloninger's temperament dimensions and the symptoms of attention deficit hyperactivity disorder (ADHD) in adults. However the underlying aetiology of these associations remains unclear. We investigate the extent to which genetic and environmental influences contribute to the relationship between temperament and ADHD, examining the ADHD symptoms of inattention (IA) and hyperactivity/impulsivity (HI) separately. Participants were 886 adult twin pairs aged 19-20 years. ADHD symptoms of IA and HI were measured using a DSM-IV based rating scale. Temperament was measured using Cloninger's Temperament and Character Inventory (TCI), across four dimensions: novelty seeking (NS), harm avoidance (HA), reward dependence (RD) and persistence (PS). The twin method was used to decompose phenotypic variance/covariance among these variables into genetic and environmental components. We found that NS was genetically associated with both ADHD symptom dimensions (IA and HI), but that HA was genetically associated with IA only. There was also some evidence of genetic association between PS, IA and HI. These findings suggest that unique profiles of temperament are genetically related to the two ADHD symptom dimensions in adults. Further work is now needed to elucidate the mechanisms that underlie both the combined and separate symptom factor domains of ADHD.
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Affiliation(s)
- Andrew Merwood
- MRC Social Genetic and Developmental Psychiatry Centre, PO80, Institute of Psychiatry, King's College London, DeCrespigny Park, London SE5 8AF, UK.
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