• Association betweenDRD2/DRD4interaction and conduct disorder: A potential developmental pathway to alcohol dependence

      Mota, Nina R.; Bau, Claiton H. D.; Banaschewski, Tobias; Buitelaar, Jan K.; Ebstein, Richard P.; Franke, Barbara; Gill, Michael; Kuntsi, Jonna; Manor, Iris; Miranda, Ana; et al. (Wiley, 2013-07-02)
    • Brain Correlates of the Interaction Between5-HTTLPRand Psychosocial Stress Mediating Attention Deficit Hyperactivity Disorder Severity

      van der Meer, Dennis; Hoekstra, Pieter J.; Zwiers, Marcel; Mennes, Maarten; Schweren, Lizanne J.; Franke, Barbara; Heslenfeld, Dirk J.; Oosterlaan, Jaap; Faraone, Stephen V.; Buitelaar, Jan K.; et al. (American Psychiatric Association Publishing, 2015-08)
      Objective: The serotonin transporter 5-HTTLPR genotype has been found to moderate the effect of stress on severity of attention deficit hyperactivity disorder (ADHD), with stronger effects of stress in carriers of the short allele than in individuals homozygous for the long allele. The underlying neurobiological mechanism of this gene-environment interaction in ADHD is unknown. The authors aimed to determine whether 5-HTTLPR moderates the effect of stress on brain gray matter volume and, if so, which brain regions mediate the effect of this gene-environment interaction on ADHD severity. Method: Structural MRI, 5-HTTLPR genotype, and stress exposure questionnaire data were available for 701 adolescents and young adults participating in the multicenter ADHD cohort NeuroIMAGE study (from 385 families; 291 with ADHD, 78 with subthreshold ADHD, 332 healthy comparison subjects; 55.8% male; average age: 17.0 years). ADHD symptom count was determined through multi-informant questionnaires. For the analysis, a whole-brain voxel-based morphometry approach was combined with mediation analysis. Results: Stress exposure was associated with significantly less gray matter volume in the precentral gyrus, middle and superior frontal gyri, frontal pole, and cingulate gyrus in S-allele carriers compared with participants homozygous for the L-allele. The association of this gene-environment interaction with ADHD symptom count was mediated by gray matter volume in the frontal pole and anterior cingulate gyrus. Conclusions: 5-HTTLPR genotype moderates the effect of stress on brain regions involved in social cognitive processing and cognitive control. Specifically, regions important for cognitive control link this gene-environment interaction to ADHD severity.
    • Consortium neuroscience of attention deficit/hyperactivity disorder and autism spectrum disorder: The ENIGMA adventure

      Hoogman, Martine; Rooij, Daan; Klein, Marieke; Boedhoe, Premika; Ilioska, Iva; Li, Ting; Patel, Yash; Postema, Merel C.; Zhang‐James, Yanli; Anagnostou, Evdokia; et al. (Wiley, 2020-05-18)
      Neuroimaging has been extensively used to study brain structure and function in individuals with attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) over the past decades. Two of the main shortcomings of the neuroimaging literature of these disorders are the small sample sizes employed and the heterogeneity of methods used. In 2013 and 2014, the ENIGMA-ADHD and ENIGMA-ASD working groups were respectively, founded with a common goal to address these limitations. Here, we provide a narrative review of the thus far completed and still ongoing projects of these working groups. Due to an implicitly hierarchical psychiatric diagnostic classification system, the fields of ADHD and ASD have developed largely in isolation, despite the considerable overlap in the occurrence of the disorders. The collaboration between the ENIGMA-ADHD and -ASD working groups seeks to bring the neuroimaging efforts of the two disorders closer together. The outcomes of case–control studies of subcortical and cortical structures showed that subcortical volumes are similarly affected in ASD and ADHD, albeit with small effect sizes. Cortical analyses identified unique differences in each disorder, but also considerable overlap between the two, specifically in cortical thickness. Ongoing work is examining alternative research questions, such as brain laterality, prediction of case–control status, and anatomical heterogeneity. In brief, great strides have been made toward fulfilling the aims of the ENIGMA collaborations, while new ideas and follow-up analyses continue that include more imaging modalities (diffusion MRI and resting-state functional MRI), collaborations with other large databases, and samples with dual diagnoses.
    • The dopamine receptor D4 7-repeat allele influences neurocognitive functioning, but this effect is moderated by age and ADHD status: An exploratory study

      Altink, Marieke E.; Rommelse, Nanda N.J.; Slaats-Willemse, Dorine I.E.; Väsquez, Alejandro Arias; Franke, Barbara; Buschgens, Cathelijne J.M.; Fliers, Ellen A.; Faraone, Stephen V.; Sergeant, Joseph A.; Oosterlaan, Jaap; et al. (Informa UK Limited, 2011-11-23)
      Objectives. Evidence suggests the involvement of the dopamine D4 receptor gene ( DRD4 ) in the pathogenesis of ADHD, but the exact mechanism is not well understood. Earlier reports on the effects of DRD4 polymorphisms on neurocognitive and neuroimaging measures are inconsistent. This study investigated the functional consequences of the 7-repeat allele of DRD4 on neurocognitive endophenotypes of ADHD in the Dutch subsample of the International Multicenter ADHD Genetics study. Methods. Participants were 350 children (5 – 11.5 years) and adolescents (11.6 – 19 years) with ADHD and their 195 non-affected siblings. An overall measure of neuropsychological functioning was derived by principal component analysis from five neurocognitive and five motor tasks. The effects of DRD4 and age were examined using Linear Mixed Model analyses. Results. The analyses were stratified for affected and non-affected participants after finding a significant three-way interaction between ADHD status, age and the 7-repeat allele. Apart from a main effect of age, a significant interaction effect of age and DRD4 was found in non-affected but not in affected participants, with non-affected adolescent carriers of the 7-repeat allele showing worse neuropsychological performance. In addition, carrying the 7-repeat allele of DRD4 was related to a significantly worse performance on verbal working memory in non-affected siblings, independent of age. Conclusions. These results might indicate that the effect of the DRD4 7-repeat allele on neuropsychological functioning is dependent on age and ADHD status.
    • Evidence for Similar Structural Brain Anomalies in Youth and Adult Attention-Deficit/Hyperactivity Disorder: A Machine Learning Analysis

      Zhang-James, Yanli; Helminen, Emily C; Liu, Jinru; Franke, Barbara; Hoogman, Martine; Faraone, Stephen V. (Cold Spring Harbor Laboratory, 2019-02-11)
      Attention-deficit/hyperactivity disorder (ADHD) affects 5% of children world-wide. Of these, two-thirds continue to have impairing symptoms of ADHD into adulthood. Although a large literature implicates structural brain differences of the disorder, it is not clear if adults with ADHD have similar neuroanatomical differences as those seen in children with recent reports from the large ENIGMA-ADHD consortium finding structural differences for children but not for adults. This paper uses deep learning neural network classification models to determine if there are neuroanatomical changes in the brains of children with ADHD that are also observed for adult ADHD, and vice versa. We found that structural MRI data can significantly separate ADHD from control participants for both children and adults. Consistent with the prior reports from ENIGMA-ADHD, prediction performance and effect sizes were better for the child than the adult samples. The model trained on adult samples significantly predicted ADHD in the child sample, suggesting that our model learned anatomical features that are common to ADHD in childhood and adulthood. These results support the continuity of ADHD’s brain differences from childhood to adulthood. In addition, our work demonstrates a novel use of neural network classification models to test hypotheses about developmental continuity.
    • Machine Learning And MRI-Based Diagnostic Models For ADHD: Are We There Yet?

      Zhang-James, Yanli; Hoogman, Martine; Franke, Barbara; Faraone, Stephen V. (Cold Spring Harbor Laboratory, 2020-10-23)
      Machine learning (ML) has been applied to develop magnetic resonance imaging (MRI)-based diagnostic classifiers for attention-deficit/hyperactivity disorder (ADHD). This systematic review examines this literature to clarify its clinical significance and to assess the implications of the various analytic methods applied. We found that, although most of studies reported the classification accuracies, they varied in choice of MRI modalities, ML models, cross-validation and testing methods, and sample sizes. We found that the accuracies of cross-validation methods inflated the performance estimation compared with those of a held-out test, compromising the model generalizability. Test accuracies have increased with publication year but were not associated with training sample sizes. Improved test accuracy over time was likely due to the use of better ML methods along with strategies to deal with data imbalances. Ultimately, large multi-modal imaging datasets, and potentially the combination with other types of data, like cognitive data and/or genetics, will be essential to achieve the goal of developing clinically useful imaging classification tools for ADHD in the future.
    • Neuropsychological intra-individual variability explains unique genetic variance of ADHD and shows suggestive linkage to chromosomes 12, 13, and 17

      Frazier-Wood, Alexis C.; Bralten, Janita; Arias-Vasquez, Alejandro; Luman, Marjolein; Ooterlaan, Jaap; Sergeant, Joseph; Faraone, Stephen V.; Buitelaar, Jan; Franke, Barbara; Kuntsi, Jonna; et al. (Wiley, 2012-01-05)
      Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable neuropsychiatric disorder that is usually accompanied by neuropsychological impairments. The use of heritable, psychometrically robust traits that show association with the disorder of interest can increase the power of gene-finding studies. Due to the robust association of intra-individual variability with ADHD on a phenotypic and genetic level, intra-individual variability is a prime candidate for such an attempt. We aimed to combine intra-individual variability measures across tasks into one more heritable measure, to examine the relatedness to other cognitive factors, and to explore the genetic underpinnings through quantitative trait linkage analysis. Intra-individual variability measures from seven tasks were available for 238 ADHD families (350 ADHD-affected and 195 non-affected children) and 147 control families (271 children). Intra-individual variability measures from seven different tasks shared common variance and could be used to construct an aggregated measure. This aggregated measure was largely independent from other cognitive factors related to ADHD and showed suggestive linkage to chromosomes 12q24.3 (LOD ¼ 2.93), 13q22.2 (LOD ¼ 2.36), and 17p13.3 (LOD ¼ 2.00). A common intra-individual variability construct can be extracted from very diverse neuropsychological tasks; this construct taps into unique genetic aspects of ADHD and may relate to loci conferring risk for ADHD (12q24.3 and 17p13.3) and possibly autism (12q24.3). Given that joining of data across sites boosts the power for genetic analyses, our findings are promising in showing that intra-individual variability measures are viable candidates for across site analyses where different tasks have been used.
    • Risk variants and polygenic architecture of disruptive behavior disorders in the context of attention-deficit/hyperactivity disorder

      Demontis, Ditte; Walters, Raymond K.; Rajagopal, Veera M.; Waldman, Irwin D.; Grove, Jakob; Als, Thomas D.; Dalsgaard, Søren; Ribasés, Marta; Bybjerg-Grauholm, Jonas; Bækvad-Hansen, Maria; et al. (Springer Science and Business Media LLC, 2021-01-25)
      Attention-Deficit/Hyperactivity Disorder (ADHD) is a childhood psychiatric disorder often comorbid with disruptive behavior disorders (DBDs). Here, we report a GWAS meta-analysis of ADHD comorbid with DBDs (ADHD + DBDs) including 3802 cases and 31,305 controls. We identify three genome-wide significant loci on chromosomes 1, 7, and 11. A meta-analysis including a Chinese cohort supports that the locus on chromosome 11 is a strong risk locus for ADHD + DBDs across European and Chinese ancestries (rs7118422, P = 3.15×10−10, OR= 1.17). We find a higher SNP heritability for ADHD + DBDs (h2 SNP = 0.34) when compared to ADHD without DBDs (h2 SNP = 0.20), high genetic correlations between ADHD + DBDs and aggressive (rg = 0.81) and anti-social behaviors (rg = 0.82), and an increased burden (polygenic score) of variants associated with ADHD and aggression in ADHD + DBDs compared to ADHD without DBDs. Our results suggest an increased load of common risk variants in ADHD + DBDs compared to ADHD without DBDs, which in part can be explained by variants associated with aggressive behavior.
    • Risk variants and polygenic architecture of disruptive behavior disorders in the context of attention-deficit/hyperactivity disorder

      Demontis, Ditte; Walters, Raymond K.; Rajagopal, Veera M.; Waldman, Irwin D.; Grove, Jakob; Als, Thomas D.; Dalsgaard, Søren; Ribasés, Marta; Bybjerg-Grauholm, Jonas; Bækvad-Hansen, Maria; et al. (Springer Science and Business Media LLC, 2021-01-25)
      Attention-Deficit/Hyperactivity Disorder (ADHD) is a childhood psychiatric disorder often comorbid with disruptive behavior disorders (DBDs). Here, we report a GWAS meta-analysis of ADHD comorbid with DBDs (ADHD + DBDs) including 3802 cases and 31,305 controls. We identify three genome-wide significant loci on chromosomes 1, 7, and 11. A meta-analysis including a Chinese cohort supports that the locus on chromosome 11 is a strong risk locus for ADHD + DBDs across European and Chinese ancestries (rs7118422, P = 3.15×10-10, OR = 1.17). We find a higher SNP heritability for ADHD + DBDs (h2SNP = 0.34) when compared to ADHD without DBDs (h2SNP = 0.20), high genetic correlations between ADHD + DBDs and aggressive (rg = 0.81) and anti-social behaviors (rg = 0.82), and an increased burden (polygenic score) of variants associated with ADHD and aggression in ADHD + DBDs compared to ADHD without DBDs. Our results suggest an increased load of common risk variants in ADHD + DBDs compared to ADHD without DBDs, which in part can be explained by variants associated with aggressive behavior.
    • Structural Brain Imaging Studies Offer Clues about the Effects of the Shared Genetic Etiology among Neuropsychiatric Disorders

      Radonjić, Nevena V.; Hess, Jonathan L.; Rovira, Paula; Andreassen, Ole; Buitelaar, Jan K.; Ching, Christopher R. K.; Franke, Barbara; Hoogman, Martine; Jahanshad, Neda; McDonald, Carrie; et al. (Cold Spring Harbor Laboratory, 2019-10-17)
      Genomewide association studies have found significant genetic correlations among many neuropsychiatric disorders. In contrast, we know much less about the degree to which structural brain alterations are similar among disorders and, if so, the degree to which such similarities have a genetic etiology. From the Enhancing Neuroimaging Genetics through Meta- Analysis (ENIGMA) consortium, we acquired standardized mean differences (SMDs) in regional brain volume and cortical thickness between cases and controls. We had data on 41 brain regions for: attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), epilepsy, major depressive disorder (MDD), obsessive compulsive disorder (OCD), and schizophrenia (SCZ). These data had been derived from 24,360 patients and 37,425 controls. The SMDs were significantly correlated between SCZ and BD, OCD, MDD, and ASD. MDD was positively correlated with BD and OCD. BD was positively correlated with OCD and negatively correlated with ADHD. These pairwise correlations among disorders were correlated with the corresponding pairwise correlations among disorders derived from genomewide association studies (r = 0.494). Our results show substantial similarities in sMRI phenotypes among neuropsychiatric disorders and suggest that these similarities are accounted for, in part, by corresponding similarities in common genetic variant architectures.