ABSTRACT
The clinical profiles and outcomes of patients with neurotrophic tropomyosin receptor kinase fusion-positive (NTRK+) solid tumors receiving standard of care other than tropomyosin receptor kinase inhibitor (TRKi) targeted therapy have not been well documented. Here, we describe the clinical characteristics of patients with NTRK+ tumors treated in clinical practice using information from a United States electronic health record-derived clinicogenomic database. We also compared survival outcomes in NTRK+ patients and matched NTRK fusion-negative (NTRK-) patients and investigated the clinical prognostic value of NTRK fusions. NTRK positivity was defined by the presence of a fusion or rearrangement involving NTRK1/2/3, determined using NGS (Foundation Medicine, Inc.). NTRK+ patients (n = 28) were diagnosed with locally advanced/metastatic solid tumors between January 1, 2011 and December 31, 2019 and had received no TRKis (e.g., entrectinib or larotrectinib) during their patient journey. The unselected NTRK-population comprised 24,903 patients, and the matched NTRK-cohort included 280 patients. NTRK+ patients tended to be younger, were more commonly not smokers, and had a shorter time from advanced diagnosis to first NGS report, compared with unselected NTRK-patients; however, these differences were not significant. Median overall survival (OS) from advanced/metastatic diagnosis was 10.2 months (95% CI, 7.2-14.1) for the NTRK+ cohort versus 10.4 months (95% CI, 6.7-14.3) for the matched NTRK-cohort; hazard ratio for death in NTRK+ versus matched NTRK-patients was 1.6 (95% CI, 1.0-2.5; P = 0.05). Genomic co-alterations were rare in the NTRK+ cohort (only two of 28 patients had a co-alteration). Overall, while hazard ratios suggest NTRK fusions may be a negative prognostic factor of survival, there are no significant indications of any favorable impact of NTRK fusions on patient outcomes. TRKis, with their high response rate and good tolerability, are likely to improve outcomes for patients compared with existing standard-of-care treatments.
Subject(s)
Neoplasms, Second Primary , Neoplasms , Gene Fusion , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Neoplasms, Second Primary/drug therapy , Oncogene Proteins, Fusion/genetics , Protein Kinase Inhibitors/therapeutic use , Receptor, trkA/genetics , Tropomyosin/geneticsABSTRACT
The Enhancing NeuroImaging Genetics through Meta-Analysis copy number variant (ENIGMA-CNV) and 22q11.2 Deletion Syndrome Working Groups (22q-ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA-CNV WG has collated CNV and magnetic resonance imaging (MRI) data from ~49,000 individuals across 38 global research sites, yielding one of the largest studies to date on the effects of CNVs on brain structures in the general population. The 22q-ENIGMA WG includes 12 international research centers that assessed over 533 individuals with a confirmed 22q11.2 deletion syndrome, 40 with 22q11.2 duplications, and 333 typically developing controls, creating the largest-ever 22q11.2 CNV neuroimaging data set. In this review, we outline the ENIGMA infrastructure and procedures for multi-site analysis of CNVs and MRI data. So far, ENIGMA has identified effects of the 22q11.2, 16p11.2 distal, 15q11.2, and 1q21.1 distal CNVs on subcortical and cortical brain structures. Each CNV is associated with differences in cognitive, neurodevelopmental and neuropsychiatric traits, with characteristic patterns of brain structural abnormalities. Evidence of gene-dosage effects on distinct brain regions also emerged, providing further insight into genotype-phenotype relationships. Taken together, these results offer a more comprehensive picture of molecular mechanisms involved in typical and atypical brain development. This "genotype-first" approach also contributes to our understanding of the etiopathogenesis of brain disorders. Finally, we outline future directions to better understand effects of CNVs on brain structure and behavior.
Subject(s)
Brain , DNA Copy Number Variations , Magnetic Resonance Imaging , Mental Disorders , Neurodevelopmental Disorders , Neuroimaging , Brain/diagnostic imaging , Brain/growth & development , Brain/pathology , Humans , Mental Disorders/diagnostic imaging , Mental Disorders/genetics , Mental Disorders/pathology , Multicenter Studies as Topic , Neurodevelopmental Disorders/diagnostic imaging , Neurodevelopmental Disorders/genetics , Neurodevelopmental Disorders/pathologyABSTRACT
Here we review the motivation for creating the enhancing neuroimaging genetics through meta-analysis (ENIGMA) Consortium and the genetic analyses undertaken by the consortium so far. We discuss the methodological challenges, findings, and future directions of the genetics working group. A major goal of the working group is tackling the reproducibility crisis affecting "candidate gene" and genome-wide association analyses in neuroimaging. To address this, we developed harmonized analytic methods, and support their use in coordinated analyses across sites worldwide, which also makes it possible to understand heterogeneity in results across sites. These efforts have resulted in the identification of hundreds of common genomic loci robustly associated with brain structure. We have found both pleiotropic and specific genetic effects associated with brain structures, as well as genetic correlations with psychiatric and neurological diseases.
Subject(s)
Brain , Genetics , Genome-Wide Association Study , Mental Disorders , Meta-Analysis as Topic , Nervous System Diseases , Neuroimaging , Brain/anatomy & histology , Brain/diagnostic imaging , Humans , Mental Disorders/diagnostic imaging , Mental Disorders/genetics , Mental Disorders/pathology , Multicenter Studies as Topic , Nervous System Diseases/diagnostic imaging , Nervous System Diseases/genetics , Nervous System Diseases/pathologyABSTRACT
MRI-derived brain measures offer a link between genes, the environment and behavior and have been widely studied in bipolar disorder (BD). However, many neuroimaging studies of BD have been underpowered, leading to varied results and uncertainty regarding effects. The Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Bipolar Disorder Working Group was formed in 2012 to empower discoveries, generate consensus findings and inform future hypothesis-driven studies of BD. Through this effort, over 150 researchers from 20 countries and 55 institutions pool data and resources to produce the largest neuroimaging studies of BD ever conducted. The ENIGMA Bipolar Disorder Working Group applies standardized processing and analysis techniques to empower large-scale meta- and mega-analyses of multimodal brain MRI and improve the replicability of studies relating brain variation to clinical and genetic data. Initial BD Working Group studies reveal widespread patterns of lower cortical thickness, subcortical volume and disrupted white matter integrity associated with BD. Findings also include mapping brain alterations of common medications like lithium, symptom patterns and clinical risk profiles and have provided further insights into the pathophysiological mechanisms of BD. Here we discuss key findings from the BD working group, its ongoing projects and future directions for large-scale, collaborative studies of mental illness.
Subject(s)
Bipolar Disorder , Cerebral Cortex , Magnetic Resonance Imaging , Neuroimaging , Bipolar Disorder/diagnostic imaging , Bipolar Disorder/pathology , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/pathology , Humans , Meta-Analysis as Topic , Multicenter Studies as TopicABSTRACT
Structural brain changes along the lineage leading to modern Homo sapiens contributed to our distinctive cognitive and social abilities. However, the evolutionarily relevant molecular variants impacting key aspects of neuroanatomy are largely unknown. Here, we integrate evolutionary annotations of the genome at diverse timescales with common variant associations from large-scale neuroimaging genetic screens. We find that alleles with evidence of recent positive polygenic selection over the past 2000-3000 years are associated with increased surface area (SA) of the entire cortex, as well as specific regions, including those involved in spoken language and visual processing. Therefore, polygenic selective pressures impact the structure of specific cortical areas even over relatively recent timescales. Moreover, common sequence variation within human gained enhancers active in the prenatal cortex is associated with postnatal global SA. We show that such variation modulates the function of a regulatory element of the developmentally relevant transcription factor HEY2 in human neural progenitor cells and is associated with structural changes in the inferior frontal cortex. These results indicate that non-coding genomic regions active during prenatal cortical development are involved in the evolution of human brain structure and identify novel regulatory elements and genes impacting modern human brain structure.
Subject(s)
Biological Evolution , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/physiology , Genetic Variation/genetics , Genome-Wide Association Study/methods , Genetic Testing/methods , Humans , Magnetic Resonance Imaging/trends , Multifactorial Inheritance/genetics , Organ Size/genetics , Quantitative Trait Loci/geneticsABSTRACT
The development and progression of solid tumors such as colorectal cancer (CRC) are known to be affected by the immune system and cell types such as T cells, natural killer (NK) cells, and natural killer T (NKT) cells are emerging as interesting targets for immunotherapy and clinical biomarker research. In addition, CD3+ and CD8+ T cell distribution in tumors has shown positive prognostic value in stage I-III CRC. Recent developments in digital computational pathology support not only classical cell density based tumor characterization, but also a more comprehensive analysis of the spatial cell organization in the tumor immune microenvironment (TiME). Leveraging that methodology in the current study, we tried to address the question of how the distribution of myeloid derived suppressor cells in TiME of primary CRC affects the function and location of cytotoxic T cells. We applied multicolored immunohistochemistry to identify monocytic (CD11b+CD14+) and granulocytic (CD11b+CD15+) myeloid cell populations together with proliferating and non-proliferating cytotoxic T cells (CD8+Ki67+/-). Through automated object detection and image registration using HALO software (IndicaLabs), we applied dedicated spatial statistics to measure the extent of overlap between the areas occupied by myeloid and T cells. With this approach, we observed distinct spatial organizational patterns of immune cells in tumors obtained from 74 treatment-naive CRC patients. Detailed analysis of inter-cell distances and myeloid-T cell spatial overlap combined with integrated gene expression data allowed to stratify patients irrespective of their mismatch repair (MMR) status or consensus molecular subgroups (CMS) classification. In addition, generation of cell distance-derived gene signatures and their mapping to the TCGA data set revealed associations between spatial immune cell distribution in TiME and certain subsets of CD8+ and CD4+ T cells. The presented study sheds a new light on myeloid and T cell interactions in TiME in CRC patients. Our results show that CRC tumors present distinct distribution patterns of not only T effector cells but also tumor resident myeloid cells, thus stressing the necessity of more comprehensive characterization of TiME in order to better predict cancer prognosis. This research emphasizes the importance of a multimodal approach by combining computational pathology with its detailed spatial statistics and gene expression profiling. Finally, our study presents a novel approach to cancer patients' characterization that can potentially be used to develop new immunotherapy strategies, not based on classical biomarkers related to CRC biology.
Subject(s)
Colorectal Neoplasms/etiology , Colorectal Neoplasms/metabolism , Myeloid-Derived Suppressor Cells/immunology , Myeloid-Derived Suppressor Cells/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Adult , Aged , Aged, 80 and over , Biomarkers , Colorectal Neoplasms/pathology , Colorectal Neoplasms/surgery , Computational Biology/methods , Disease Susceptibility , Female , Gene Expression Profiling/methods , Humans , Immunohistochemistry , Immunomodulation , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Lymphocytes, Tumor-Infiltrating/pathology , Male , Middle Aged , Neoplasm Grading , Neoplasm Metastasis , Neoplasm Staging , Prognosis , Tumor Microenvironment/genetics , Tumor Microenvironment/immunologyABSTRACT
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder.
Subject(s)
Cerebral Cortex/anatomy & histology , Genetic Variation , Attention Deficit Disorder with Hyperactivity/genetics , Brain Mapping , Cognition , Genetic Loci , Genome-Wide Association Study , Humans , Magnetic Resonance Imaging , Organ Size/genetics , Parkinson Disease/geneticsABSTRACT
Brain structural covariance networks reflect covariation in morphology of different brain areas and are thought to reflect common trajectories in brain development and maturation. Large-scale investigation of structural covariance networks in obsessive-compulsive disorder (OCD) may provide clues to the pathophysiology of this neurodevelopmental disorder. Using T1-weighted MRI scans acquired from 1616 individuals with OCD and 1463 healthy controls across 37 datasets participating in the ENIGMA-OCD Working Group, we calculated intra-individual brain structural covariance networks (using the bilaterally-averaged values of 33 cortical surface areas, 33 cortical thickness values, and six subcortical volumes), in which edge weights were proportional to the similarity between two brain morphological features in terms of deviation from healthy controls (i.e. z-score transformed). Global networks were characterized using measures of network segregation (clustering and modularity), network integration (global efficiency), and their balance (small-worldness), and their community membership was assessed. Hub profiling of regional networks was undertaken using measures of betweenness, closeness, and eigenvector centrality. Individually calculated network measures were integrated across the 37 datasets using a meta-analytical approach. These network measures were summated across the network density range of K = 0.10-0.25 per participant, and were integrated across the 37 datasets using a meta-analytical approach. Compared with healthy controls, at a global level, the structural covariance networks of OCD showed lower clustering (P < 0.0001), lower modularity (P < 0.0001), and lower small-worldness (P = 0.017). Detection of community membership emphasized lower network segregation in OCD compared to healthy controls. At the regional level, there were lower (rank-transformed) centrality values in OCD for volume of caudate nucleus and thalamus, and surface area of paracentral cortex, indicative of altered distribution of brain hubs. Centrality of cingulate and orbito-frontal as well as other brain areas was associated with OCD illness duration, suggesting greater involvement of these brain areas with illness chronicity. In summary, the findings of this study, the largest brain structural covariance study of OCD to date, point to a less segregated organization of structural covariance networks in OCD, and reorganization of brain hubs. The segregation findings suggest a possible signature of altered brain morphometry in OCD, while the hub findings point to OCD-related alterations in trajectories of brain development and maturation, particularly in cingulate and orbitofrontal regions.
Subject(s)
Brain/physiopathology , Cerebral Cortex/physiopathology , Neural Pathways/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Adult , Brain/pathology , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Obsessive-Compulsive Disorder/pathologyABSTRACT
Bipolar disorders (BDs) are among the leading causes of morbidity and disability. Objective biological markers, such as those based on brain imaging, could aid in clinical management of BD. Machine learning (ML) brings neuroimaging analyses to individual subject level and may potentially allow for their diagnostic use. However, fair and optimal application of ML requires large, multi-site datasets. We applied ML (support vector machines) to MRI data (regional cortical thickness, surface area, subcortical volumes) from 853 BD and 2167 control participants from 13 cohorts in the ENIGMA consortium. We attempted to differentiate BD from control participants, investigated different data handling strategies and studied the neuroimaging/clinical features most important for classification. Individual site accuracies ranged from 45.23% to 81.07%. Aggregate subject-level analyses yielded the highest accuracy (65.23%, 95% CI = 63.47-67.00, ROC-AUC = 71.49%, 95% CI = 69.39-73.59), followed by leave-one-site-out cross-validation (accuracy = 58.67%, 95% CI = 56.70-60.63). Meta-analysis of individual site accuracies did not provide above chance results. There was substantial agreement between the regions that contributed to identification of BD participants in the best performing site and in the aggregate dataset (Cohen's Kappa = 0.83, 95% CI = 0.829-0.831). Treatment with anticonvulsants and age were associated with greater odds of correct classification. Although short of the 80% clinically relevant accuracy threshold, the results are promising and provide a fair and realistic estimate of classification performance, which can be achieved in a large, ecologically valid, multi-site sample of BD participants based on regional neurostructural measures. Furthermore, the significant classification in different samples was based on plausible and similar neuroanatomical features. Future multi-site studies should move towards sharing of raw/voxelwise neuroimaging data.
Subject(s)
Bipolar Disorder , Bipolar Disorder/diagnostic imaging , Brain/diagnostic imaging , Humans , Machine Learning , Magnetic Resonance Imaging , NeuroimagingABSTRACT
Prior to and following the publication of this article the authors noted that the complete list of authors was not included in the main article and was only present in Supplementary Table 1. The author list in the original article has now been updated to include all authors, and Supplementary Table 1 has been removed. All other supplementary files have now been updated accordingly. Furthermore, in Table 1 of this Article, the replication cohort for the row Close relative in data set, n (%) was incorrect. All values have now been corrected to 0(0%). The publishers would like to apologise for this error and the inconvenience it may have caused.
ABSTRACT
Carriers of large recurrent copy number variants (CNVs) have a higher risk of developing neurodevelopmental disorders. The 16p11.2 distal CNV predisposes carriers to e.g., autism spectrum disorder and schizophrenia. We compared subcortical brain volumes of 12 16p11.2 distal deletion and 12 duplication carriers to 6882 non-carriers from the large-scale brain Magnetic Resonance Imaging collaboration, ENIGMA-CNV. After stringent CNV calling procedures, and standardized FreeSurfer image analysis, we found negative dose-response associations with copy number on intracranial volume and on regional caudate, pallidum and putamen volumes (ß = -0.71 to -1.37; P < 0.0005). In an independent sample, consistent results were obtained, with significant effects in the pallidum (ß = -0.95, P = 0.0042). The two data sets combined showed significant negative dose-response for the accumbens, caudate, pallidum, putamen and ICV (P = 0.0032, 8.9 × 10-6, 1.7 × 10-9, 3.5 × 10-12 and 1.0 × 10-4, respectively). Full scale IQ was lower in both deletion and duplication carriers compared to non-carriers. This is the first brain MRI study of the impact of the 16p11.2 distal CNV, and we demonstrate a specific effect on subcortical brain structures, suggesting a neuropathological pattern underlying the neurodevelopmental syndromes.
Subject(s)
Autistic Disorder/genetics , Basal Ganglia/pathology , Chromosome Disorders/genetics , DNA Copy Number Variations/genetics , Intellectual Disability/genetics , Adult , Autism Spectrum Disorder/genetics , Brain/pathology , Chromosome Deletion , Chromosome Duplication , Chromosomes, Human, Pair 16/genetics , Databases, Factual , Female , Globus Pallidus/pathology , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neurodevelopmental Disorders/genetics , Organ Size/genetics , Putamen/pathology , Schizophrenia/geneticsABSTRACT
Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease.
Subject(s)
Brain/anatomy & histology , Brain/metabolism , Drosophila melanogaster/metabolism , Genetic Variation , Genome-Wide Association Study , Neurodevelopmental Disorders/genetics , Neurodevelopmental Disorders/pathology , Adult , Aged , Animals , Cohort Studies , Drosophila melanogaster/genetics , Drosophila melanogaster/growth & development , Humans , Magnetic Resonance Imaging , Middle Aged , Organ SizeABSTRACT
Brain lobar volumes are heritable but genetic studies are limited. We performed genome-wide association studies of frontal, occipital, parietal and temporal lobe volumes in 16,016 individuals, and replicated our findings in 8,789 individuals. We identified six genetic loci associated with specific lobar volumes independent of intracranial volume. Two loci, associated with occipital (6q22.32) and temporal lobe volume (12q14.3), were previously reported to associate with intracranial and hippocampal volume, respectively. We identified four loci previously unknown to affect brain volumes: 3q24 for parietal lobe volume, and 1q22, 4p16.3 and 14q23.1 for occipital lobe volume. The associated variants were located in regions enriched for histone modifications (DAAM1 and THBS3), or close to genes causing Mendelian brain-related diseases (ZIC4 and FGFRL1). No genetic overlap between lobar volumes and neurological or psychiatric diseases was observed. Our findings reveal part of the complex genetics underlying brain development and suggest a role for regulatory regions in determining brain volumes.
Subject(s)
Frontal Lobe/growth & development , Genetic Loci , Genetic Variation , Occipital Lobe/growth & development , Parietal Lobe/growth & development , Temporal Lobe/growth & development , Frontal Lobe/diagnostic imaging , Gene Expression Regulation, Developmental , Genome-Wide Association Study , Genotype , Heredity , Humans , Magnetic Resonance Imaging , Occipital Lobe/diagnostic imaging , Organ Size/genetics , Parietal Lobe/diagnostic imaging , Phenotype , Temporal Lobe/drug effects , United KingdomABSTRACT
Genome-wide association studies (GWAS) link full genome data to a handful of traits. However, in neuroimaging studies, there is an almost unlimited number of traits that can be extracted for full image-wide big data analyses. Large populations are needed to achieve the necessary power to detect statistically significant effects, emphasizing the need to pool data across multiple studies. Neuroimaging consortia, e.g., ENIGMA and CHARGE, are now analyzing MRI data from over 30,000 individuals. Distributed processing protocols extract harmonized features at each site, and pool together only the cohort statistics using meta analysis to avoid data sharing. To date, such MRI projects have focused on single measures such as hippocampal volume, yet voxelwise analyses (e.g., tensor-based morphometry; TBM) may help better localize statistical effects. This can lead to $10^{13}$1013 tests for GWAS and become underpowered. We developed an analytical framework for multi-site TBM by performing multi-channel registration to cohort-specific templates. Our results highlight the reliability of the method and the added power over alternative options while preserving single site specificity and opening the doors for well-powered image-wide genome-wide discoveries.
Subject(s)
Computational Biology/methods , Genome-Wide Association Study/methods , Neuroimaging/methods , Adult , Aged , Aged, 80 and over , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/genetics , Brain/diagnostic imaging , Databases, Factual , Female , Humans , Magnetic Resonance Imaging , Male , Meta-Analysis as Topic , Middle Aged , Polymorphism, Single Nucleotide/genetics , Young AdultABSTRACT
There have been considerable recent advances in understanding the genetic architecture of Tourette syndrome (TS) as well as its underlying neurocircuitry. However, the mechanisms by which genetic variation that increases risk for TS-and its main symptom dimensions-influence relevant brain regions are poorly understood. Here we undertook a genome-wide investigation of the overlap between TS genetic risk and genetic influences on the volume of specific subcortical brain structures that have been implicated in TS. We obtained summary statistics for the most recent TS genome-wide association study (GWAS) from the TS Psychiatric Genomics Consortium Working Group (4644 cases and 8695 controls) and GWAS of subcortical volumes from the ENIGMA consortium (30,717 individuals). We also undertook analyses using GWAS summary statistics of key symptom factors in TS, namely social disinhibition and symmetry behaviour. SNP effect concordance analysis (SECA) was used to examine genetic pleiotropy-the same SNP affecting two traits-and concordance-the agreement in single nucelotide polymorphism (SNP) effect directions across these two traits. In addition, a conditional false discovery rate (FDR) analysis was performed, conditioning the TS risk variants on each of the seven subcortical and the intracranial brain volume GWAS. Linkage disequilibrium score regression (LDSR) was used as validation of the SECA method. SECA revealed significant pleiotropy between TS and putamen (p = 2 × 10-4) and caudate (p = 4 × 10-4) volumes, independent of direction of effect, and significant concordance between TS and lower thalamic volume (p = 1 × 10-3). LDSR lent additional support for the association between TS and thalamus volume (p = 5.85 × 10-2). Furthermore, SECA revealed significant evidence of concordance between the social disinhibition symptom dimension and lower thalamus volume (p = 1 × 10-3), as well as concordance between symmetry behaviour and greater putamen volume (p = 7 × 10-4). Conditional FDR analysis further revealed novel variants significantly associated with TS (p < 8 × 10-7) when conditioning on intracranial (rs2708146, q = 0.046; and rs72853320, q = 0.035) and hippocampal (rs1922786, q = 0.001) volumes, respectively. These data indicate concordance for genetic variation involved in disorder risk and subcortical brain volumes in TS. Further work with larger samples is needed to fully delineate the genetic architecture of these disorders and their underlying neurocircuitry.
Subject(s)
Hippocampus/pathology , Neural Pathways/physiopathology , Polymorphism, Single Nucleotide , Putamen/pathology , Tourette Syndrome/genetics , Case-Control Studies , DNA Mutational Analysis , Genetic Pleiotropy , Genetic Predisposition to Disease , Genome-Wide Association Study , Hippocampus/diagnostic imaging , Humans , Linkage Disequilibrium , Magnetic Resonance Imaging , Putamen/diagnostic imaging , Tourette Syndrome/physiopathologyABSTRACT
OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is a common and highly heritable neurodevelopmental disorder with a complex pathophysiology. Intracranial volume (ICV) and volumes of the nucleus accumbens, amygdala, caudate nucleus, hippocampus, and putamen are smaller in people with ADHD compared with healthy individuals. The authors investigated the overlap between common genetic variation associated with ADHD risk and these brain volume measures to identify underlying biological processes contributing to the disorder. METHODS: The authors combined genome-wide association results from the largest available studies of ADHD (N=55,374) and brain volumes (N=11,221-24,704), using a set of complementary methods to investigate overlap at the level of global common variant genetic architecture and at the single variant level. RESULTS: Analyses revealed a significant negative genetic correlation between ADHD and ICV (rg=-0.22). Meta-analysis of single variants revealed two significant loci of interest associated with both ADHD risk and ICV; four additional loci were identified for ADHD and volumes of the amygdala, caudate nucleus, and putamen. Exploratory gene-based and gene-set analyses in the ADHD-ICV meta-analytic data showed association with variation in neurite outgrowth-related genes. CONCLUSIONS: This is the first genome-wide study to show significant genetic overlap between brain volume measures and ADHD, both on the global and the single variant level. Variants linked to smaller ICV were associated with increased ADHD risk. These findings can help us develop new hypotheses about biological mechanisms by which brain structure alterations may be involved in ADHD disease etiology.
Subject(s)
Attention Deficit Disorder with Hyperactivity/genetics , Brain/pathology , Amygdala/pathology , Attention Deficit Disorder with Hyperactivity/etiology , Attention Deficit Disorder with Hyperactivity/pathology , Case-Control Studies , Caudate Nucleus/pathology , Genetic Markers/genetics , Genome-Wide Association Study , Hippocampus/pathology , Humans , Linkage Disequilibrium/genetics , Nucleus Accumbens/pathology , Organ Size/genetics , Polymorphism, Single Nucleotide/genetics , Putamen/pathology , Quantitative Trait Loci/geneticsABSTRACT
BACKGROUND: There have been considerable recent advances in understanding the genetic architecture of anxiety disorders and posttraumatic stress disorder (PTSD), as well as the underlying neurocircuitry of these disorders. However, there is little work on the concordance of genetic variations that increase risk for these conditions, and that influence subcortical brain structures. We undertook a genome-wide investigation of the overlap between the genetic influences from single nucleotide polymorphisms (SNPs) on volumes of subcortical brain structures and genetic risk for anxiety disorders and PTSD. METHOD: We obtained summary statistics of genome-wide association studies (GWAS) of anxiety disorders (Ncasesâ¯=â¯7016, Ncontrolsâ¯=â¯14,745), PTSD (European sample; Ncasesâ¯=â¯2424, Ncontrolsâ¯=â¯7113) and of subcortical brain structures (Nâ¯=â¯13,171). SNP Effect Concordance Analysis (SECA) and Linkage Disequilibrium (LD) Score Regression were used to examine genetic pleiotropy, concordance, and genome-wide correlations respectively. SECAs conditional false discovery was used to identify specific risk variants associated with anxiety disorders or PTSD when conditioning on brain related traits. RESULTS: For anxiety disorders, we found evidence of significant concordance between increased anxiety risk variants and variants associated with smaller amygdala volume. Further, by conditioning on brain volume GWAS, we identified novel variants that associate with smaller brain volumes and increase risk for disorders: rs56242606 was found to increase risk for anxiety disorders, while two variants (rs6470292 and rs683250) increase risk for PTSD, when conditioning on the GWAS of putamen volume. LIMITATIONS: Despite using the largest available GWAS summary statistics, the analyses were limited by sample size. CONCLUSIONS: These preliminary data indicate that there is genome wide concordance between genetic risk factors for anxiety disorders and those for smaller amygdala volume, which is consistent with research that supports the involvement of the amygdala in anxiety disorders. It is notable that a genetic variant that contributes to both reduced putamen volume and PTSD plays a key role in the glutamatergic system. Further work with GWAS summary statistics from larger samples, and a more extensive look at the genetics underlying brain circuits, is needed to fully delineate the genetic architecture of these disorders and their underlying neurocircuitry.
Subject(s)
Anxiety Disorders/genetics , Anxiety Disorders/psychology , Genetic Variation/genetics , Neural Pathways/physiopathology , Stress Disorders, Post-Traumatic/genetics , Stress Disorders, Post-Traumatic/psychology , Amygdala/diagnostic imaging , Anxiety Disorders/physiopathology , Brain/diagnostic imaging , Female , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Linkage Disequilibrium , Male , Polymorphism, Single Nucleotide/genetics , Risk Factors , Stress Disorders, Post-Traumatic/physiopathologyABSTRACT
BACKGROUND: The profile of cortical neuroanatomical abnormalities in schizophrenia is not fully understood, despite hundreds of published structural brain imaging studies. This study presents the first meta-analysis of cortical thickness and surface area abnormalities in schizophrenia conducted by the ENIGMA (Enhancing Neuro Imaging Genetics through Meta Analysis) Schizophrenia Working Group. METHODS: The study included data from 4474 individuals with schizophrenia (mean age, 32.3 years; range, 11-78 years; 66% male) and 5098 healthy volunteers (mean age, 32.8 years; range, 10-87 years; 53% male) assessed with standardized methods at 39 centers worldwide. RESULTS: Compared with healthy volunteers, individuals with schizophrenia have widespread thinner cortex (left/right hemisphere: Cohen's d = -0.530/-0.516) and smaller surface area (left/right hemisphere: Cohen's d = -0.251/-0.254), with the largest effect sizes for both in frontal and temporal lobe regions. Regional group differences in cortical thickness remained significant when statistically controlling for global cortical thickness, suggesting regional specificity. In contrast, effects for cortical surface area appear global. Case-control, negative, cortical thickness effect sizes were two to three times larger in individuals receiving antipsychotic medication relative to unmedicated individuals. Negative correlations between age and bilateral temporal pole thickness were stronger in individuals with schizophrenia than in healthy volunteers. Regional cortical thickness showed significant negative correlations with normalized medication dose, symptom severity, and duration of illness and positive correlations with age at onset. CONCLUSIONS: The findings indicate that the ENIGMA meta-analysis approach can achieve robust findings in clinical neuroscience studies; also, medication effects should be taken into account in future genetic association studies of cortical thickness in schizophrenia.
Subject(s)
Brain/pathology , Schizophrenia/diagnostic imaging , Schizophrenia/pathology , Adolescent , Adult , Age of Onset , Aged , Brain/diagnostic imaging , Case-Control Studies , Child , Female , Frontal Lobe/diagnostic imaging , Frontal Lobe/pathology , Humans , Linear Models , Magnetic Resonance Imaging , Male , Middle Aged , Neuroimaging , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/pathology , Severity of Illness Index , Temporal Lobe/diagnostic imaging , Temporal Lobe/pathology , Young AdultABSTRACT
BACKGROUND: Many studies have identified changes in the brain associated with obsessive-compulsive disorder (OCD), but few have examined the relationship between genetic determinants of OCD and brain variation.AimsWe present the first genome-wide investigation of overlapping genetic risk for OCD and genetic influences on subcortical brain structures. METHOD: Using single nucleotide polymorphism effect concordance analysis, we measured genetic overlap between the first genome-wide association study (GWAS) of OCD (1465 participants with OCD, 5557 controls) and recent GWASs of eight subcortical brain volumes (13 171 participants). RESULTS: We found evidence of significant positive concordance between OCD risk variants and variants associated with greater nucleus accumbens and putamen volumes. When conditioning OCD risk variants on brain volume, variants influencing putamen, amygdala and thalamus volumes were associated with risk for OCD. CONCLUSIONS: These results are consistent with current OCD neurocircuitry models. Further evidence will clarify the relationship between putamen volume and OCD risk, and the roles of the detected variants in this disorder.Declaration of interestThe authors have declared that no competing interests exist.