1
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Castro CP, Diehl AG, Boyle AP. Challenges in screening for de novo noncoding variants contributing to genetically complex phenotypes. HGG ADVANCES 2023; 4:100210. [PMID: 37305558 PMCID: PMC10248550 DOI: 10.1016/j.xhgg.2023.100210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 05/15/2023] [Indexed: 06/13/2023] Open
Abstract
Understanding the genetic basis for complex, heterogeneous disorders, such as autism spectrum disorder (ASD), is a persistent challenge in human medicine. Owing to their phenotypic complexity, the genetic mechanisms underlying these disorders may be highly variable across individual patients. Furthermore, much of their heritability is unexplained by known regulatory or coding variants. Indeed, there is evidence that much of the causal genetic variation stems from rare and de novo variants arising from ongoing mutation. These variants occur mostly in noncoding regions, likely affecting regulatory processes for genes linked to the phenotype of interest. However, because there is no uniform code for assessing regulatory function, it is difficult to separate these mutations into likely functional and nonfunctional subsets. This makes finding associations between complex diseases and potentially causal de novo single-nucleotide variants (dnSNVs) a difficult task. To date, most published studies have struggled to find any significant associations between dnSNVs from ASD patients and any class of known regulatory elements. We sought to identify the underlying reasons for this and present strategies for overcoming these challenges. We show that, contrary to previous claims, the main reason for failure to find robust statistical enrichments is not only the number of families sampled, but also the quality and relevance to ASD of the annotations used to prioritize dnSNVs, and the reliability of the set of dnSNVs itself. We present a list of recommendations for designing future studies of this sort that will help researchers avoid common pitfalls.
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Affiliation(s)
- Christopher P. Castro
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Adam G. Diehl
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alan P. Boyle
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
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2
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Tabbaa M, Knoll A, Levitt P. Mouse population genetics phenocopies heterogeneity of human Chd8 haploinsufficiency. Neuron 2023; 111:539-556.e5. [PMID: 36738737 PMCID: PMC9960295 DOI: 10.1016/j.neuron.2023.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/13/2022] [Accepted: 01/11/2023] [Indexed: 02/05/2023]
Abstract
Preclinical models of neurodevelopmental disorders typically use single inbred mouse strains, which fail to capture the genetic diversity and symptom heterogeneity that is common clinically. We tested whether modeling genetic background diversity in mouse genetic reference panels would recapitulate population and individual differences in responses to a syndromic mutation in the high-confidence autism risk gene, CHD8. We measured clinically relevant phenotypes in >1,000 mice from 33 strains, including brain and body weights and cognition, activity, anxiety, and social behaviors, using 5 behavioral assays: cued fear conditioning, open field tests in dark and bright light, direct social interaction, and social dominance. Trait disruptions mimicked those seen clinically, with robust strain and sex differences. Some strains exhibited large effect-size trait disruptions, sometimes in opposite directions, and-remarkably-others expressed resilience. Therefore, systematically introducing genetic diversity into models of neurodevelopmental disorders provides a better framework for discovering individual differences in symptom etiologies.
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Affiliation(s)
- Manal Tabbaa
- Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA 90027, USA; Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA
| | - Allison Knoll
- Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA 90027, USA; Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA
| | - Pat Levitt
- Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA 90027, USA; Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA.
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3
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Willsey HR, Willsey AJ, Wang B, State MW. Genomics, convergent neuroscience and progress in understanding autism spectrum disorder. Nat Rev Neurosci 2022; 23:323-341. [PMID: 35440779 PMCID: PMC10693992 DOI: 10.1038/s41583-022-00576-7] [Citation(s) in RCA: 73] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2022] [Indexed: 12/31/2022]
Abstract
More than a hundred genes have been identified that, when disrupted, impart large risk for autism spectrum disorder (ASD). Current knowledge about the encoded proteins - although incomplete - points to a very wide range of developmentally dynamic and diverse biological processes. Moreover, the core symptoms of ASD involve distinctly human characteristics, presenting challenges to interpreting evolutionarily distant model systems. Indeed, despite a decade of striking progress in gene discovery, an actionable understanding of pathobiology remains elusive. Increasingly, convergent neuroscience approaches have been recognized as an important complement to traditional uses of genetics to illuminate the biology of human disorders. These methods seek to identify intersection among molecular-level, cellular-level and circuit-level functions across multiple risk genes and have highlighted developing excitatory neurons in the human mid-gestational prefrontal cortex as an important pathobiological nexus in ASD. In addition, neurogenesis, chromatin modification and synaptic function have emerged as key potential mediators of genetic vulnerability. The continued expansion of foundational 'omics' data sets, the application of higher-throughput model systems and incorporating developmental trajectories and sex differences into future analyses will refine and extend these results. Ultimately, a systems-level understanding of ASD genetic risk holds promise for clarifying pathobiology and advancing therapeutics.
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Affiliation(s)
- Helen Rankin Willsey
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - A Jeremy Willsey
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA.
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA, USA.
| | - Belinda Wang
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
- Langley Porter Psychiatric Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Matthew W State
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA.
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA, USA.
- Langley Porter Psychiatric Institute, University of California, San Francisco, San Francisco, CA, USA.
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4
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PTEN mutations in autism spectrum disorder and congenital hydrocephalus: developmental pleiotropy and therapeutic targets. Trends Neurosci 2021; 44:961-976. [PMID: 34625286 DOI: 10.1016/j.tins.2021.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 12/27/2022]
Abstract
The lack of effective treatments for autism spectrum disorder (ASD) and congenital hydrocephalus (CH) reflects the limited understanding of the biology underlying these common neurodevelopmental disorders. Although ASD and CH have been extensively studied as independent entities, recent human genomic and preclinical animal studies have uncovered shared molecular pathophysiology. Here, we review and discuss phenotypic, genomic, and molecular similarities between ASD and CH, and identify the PTEN-PI3K-mTOR (phosphatase and tensin homolog-phosphoinositide 3-kinase-mammalian target of rapamycin) pathway as a common underlying mechanism that holds diagnostic, prognostic, and therapeutic promise for individuals with ASD and CH.
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5
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Enriquez KD, Gupta AR, Hoffman EJ. Signaling Pathways and Sex Differential Processes in Autism Spectrum Disorder. Front Psychiatry 2021; 12:716673. [PMID: 34690830 PMCID: PMC8531220 DOI: 10.3389/fpsyt.2021.716673] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 09/02/2021] [Indexed: 12/21/2022] Open
Abstract
Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders associated with deficits in social communication and restrictive, repetitive patterns of behavior, that affect up to 1 in 54 children. ASDs clearly demonstrate a male bias, occurring ~4 times more frequently in males than females, though the basis for this male predominance is not well-understood. In recent years, ASD risk gene discovery has accelerated, with many whole-exome sequencing studies identifying genes that converge on common pathways, such as neuronal communication and regulation of gene expression. ASD genetics studies have suggested that there may be a "female protective effect," such that females may have a higher threshold for ASD risk, yet its etiology is not well-understood. Here, we review common biological pathways implicated by ASD genetics studies as well as recent analyses of sex differential processes in ASD using imaging genomics, transcriptomics, and animal models. Additionally, we discuss recent investigations of ASD risk genes that have suggested a potential role for estrogens as modulators of biological pathways in ASD, and highlight relevant molecular and cellular pathways downstream of estrogen signaling as potential avenues for further investigation.
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Affiliation(s)
- Kristen D Enriquez
- Program on Neurogenetics, Child Study Center, Yale University School of Medicine, New Haven, CT, United States
| | - Abha R Gupta
- Program on Neurogenetics, Child Study Center, Yale University School of Medicine, New Haven, CT, United States.,Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
| | - Ellen J Hoffman
- Program on Neurogenetics, Child Study Center, Yale University School of Medicine, New Haven, CT, United States.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
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6
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Beversdorf DQ, Shah A, Jhin A, Noel-MacDonnell J, Hecht P, Ferguson BJ, Bruce D, Tilley M, Talebizadeh Z. microRNAs and Gene-Environment Interactions in Autism: Effects of Prenatal Maternal Stress and the SERT Gene on Maternal microRNA Expression. Front Psychiatry 2021; 12:668577. [PMID: 34290629 PMCID: PMC8288023 DOI: 10.3389/fpsyt.2021.668577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 05/24/2021] [Indexed: 12/16/2022] Open
Abstract
Background: Genetics and environment both are critical in autism spectrum disorder (ASD), but their interaction (G × E) is less understood. Numerous studies have shown higher incidence of stress exposures during pregnancies with children later diagnosed with ASD. However, many stress-exposed mothers have unaffected children. The serotonin transporter (SERT) gene affects stress reactivity. Two independent samples have shown that the association between maternal stress exposure and ASD is greatest with maternal presence of the SERT short (S)-allele (deletion in the promoter region). MicroRNAs play a regulatory role in the serotonergic pathway and in prenatal stress and are therefore potential mechanistic targets in this setting. Design/methods: We profiled microRNA expression in blood from mothers of children with ASD, with known stress exposure during pregnancy. Samples were divided into groups based on SERT genotypes (LL/LS/SS) and prenatal stress level (high/low). Results: Two thousand five hundred mature microRNAs were examined. The ANOVA analysis showed differential expression (DE) of 119 microRNAs; 90 were DE in high- vs. low-stress groups (stress-dependent). Two (miR-1224-5p, miR-331-3p) were recently reported by our group to exhibit stress-dependent expression in rodent brain samples from embryos exposed to prenatal stress. Another, miR-145-5p, is associated with maternal stress. Across SERT genotypes, with high stress exposure, 20 significantly DE microRNAs were detected, five were stress-dependent. These microRNAs may be candidates for stress × SERT genotype interactions. This is remarkable as these changes were from mothers several years after stress-exposed pregnancies. Conclusions: Our study provides evidence for epigenetic alterations in relation to a G × E model (prenatal maternal stress × SERT gene) in ASD.
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Affiliation(s)
- David Q Beversdorf
- Departments of Radiology, Neurology, and Psychological Sciences, William and Nancy Thompson Endowed Chair in Radiology, University of Missouri, Columbia, MO, United States.,Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, United States
| | - Ayten Shah
- Children's Mercy Hospital, Kansas City, MO, United States
| | - Allison Jhin
- Kansas City University, Kansas City, MO, United States
| | - Janelle Noel-MacDonnell
- Children's Mercy Hospital and University of Missouri-Kansas City School of Medicine, Kansas City, MO, United States
| | - Patrick Hecht
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, United States
| | - Bradley J Ferguson
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO, United States.,Health Psychology, Radiology, and Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, Columbia, MO, United States
| | - Danielle Bruce
- Department of Biology, Central Methodist University, Fayette, MO, United States
| | - Michael Tilley
- Department of Biology, Central Methodist University, Fayette, MO, United States
| | - Zohreh Talebizadeh
- Children's Mercy Hospital and University of Missouri-Kansas City School of Medicine, Kansas City, MO, United States
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7
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Garcia-Forn M, Boitnott A, Akpinar Z, De Rubeis S. Linking Autism Risk Genes to Disruption of Cortical Development. Cells 2020; 9:cells9112500. [PMID: 33218123 PMCID: PMC7698947 DOI: 10.3390/cells9112500] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/10/2020] [Accepted: 11/15/2020] [Indexed: 02/06/2023] Open
Abstract
Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder characterized by impairments in social communication and social interaction, and the presence of repetitive behaviors and/or restricted interests. In the past few years, large-scale whole-exome sequencing and genome-wide association studies have made enormous progress in our understanding of the genetic risk architecture of ASD. While showing a complex and heterogeneous landscape, these studies have led to the identification of genetic loci associated with ASD risk. The intersection of genetic and transcriptomic analyses have also begun to shed light on functional convergences between risk genes, with the mid-fetal development of the cerebral cortex emerging as a critical nexus for ASD. In this review, we provide a concise summary of the latest genetic discoveries on ASD. We then discuss the studies in postmortem tissues, stem cell models, and rodent models that implicate recently identified ASD risk genes in cortical development.
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Affiliation(s)
- Marta Garcia-Forn
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.G.-F.); (A.B.); (Z.A.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Andrea Boitnott
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.G.-F.); (A.B.); (Z.A.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Zeynep Akpinar
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.G.-F.); (A.B.); (Z.A.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Psychology, College of Arts and Sciences, New York University, New York, NY 10003, USA
| | - Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.G.-F.); (A.B.); (Z.A.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Correspondence: ; Tel.: +1-212-241-0179
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8
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Palazzo L, Mikolčević P, Mikoč A, Ahel I. ADP-ribosylation signalling and human disease. Open Biol 2019; 9:190041. [PMID: 30991935 PMCID: PMC6501648 DOI: 10.1098/rsob.190041] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 03/22/2019] [Indexed: 02/06/2023] Open
Abstract
ADP-ribosylation (ADPr) is a reversible post-translational modification of proteins, which controls major cellular and biological processes, including DNA damage repair, cell proliferation and differentiation, metabolism, stress and immune responses. In order to maintain the cellular homeostasis, diverse ADP-ribosyl transferases and hydrolases are involved in the fine-tuning of ADPr systems. The control of ADPr network is vital, and dysregulation of enzymes involved in the regulation of ADPr signalling has been linked to a number of inherited and acquired human diseases, such as several neurological disorders and in cancer. Conversely, the therapeutic manipulation of ADPr has been shown to ameliorate several disorders in both human and animal models. These include cardiovascular, inflammatory, autoimmune and neurological disorders. Herein, we summarize the recent findings in the field of ADPr, which support the impact of this modification in human pathophysiology and highlight the curative potential of targeting ADPr for translational and molecular medicine.
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Affiliation(s)
- Luca Palazzo
- Institute of Protein Biochemistry, National Research Council, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Petra Mikolčević
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Andreja Mikoč
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, OX1 3RE Oxford, UK
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9
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Guang S, Pang N, Deng X, Yang L, He F, Wu L, Chen C, Yin F, Peng J. Synaptopathology Involved in Autism Spectrum Disorder. Front Cell Neurosci 2018; 12:470. [PMID: 30627085 PMCID: PMC6309163 DOI: 10.3389/fncel.2018.00470] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 11/19/2018] [Indexed: 12/24/2022] Open
Abstract
Autism spectrum disorder (ASD) encompasses a group of multifactorial neurodevelopmental disorders characterized by impaired social communication, social interaction and repetitive behaviors. ASD affects 1 in 59 children, and is about 4 times more common among boys than among girls. Strong genetic components, together with environmental factors in the early stage of development, contribute to the pathogenesis of ASD. Multiple studies have revealed that mutations in genes like NRXN, NLGN, SHANK, TSC1/2, FMR1, and MECP2 converge on common cellular pathways that intersect at synapses. These genes encode cell adhesion molecules, scaffolding proteins and proteins involved in synaptic transcription, protein synthesis and degradation, affecting various aspects of synapses including synapse formation and elimination, synaptic transmission and plasticity. This suggests that the pathogenesis of ASD may, at least in part, be attributed to synaptic dysfunction. In this article, we will review major genes and signaling pathways implicated in synaptic abnormalities underlying ASD, and discuss molecular, cellular and functional studies of ASD experimental models.
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Affiliation(s)
- Shiqi Guang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Xiaolu Deng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Liwen Wu
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Chen Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
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10
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Codina-Solà M, Pérez-Jurado LA, Cuscó I, Serra-Juhé C. Provision of Genetic Services for Autism and its Impact on Spanish Families. J Autism Dev Disord 2018; 47:2947-2956. [PMID: 28681252 PMCID: PMC5602032 DOI: 10.1007/s10803-017-3203-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Although a genetic evaluation can identify the etiology in 15-30% of individuals with autism spectrum disorder, several studies show an underuse of genetic services by affected families. We have explored the access to genetic services and perception of genetics and recurrence risk in parents of autistic children in Spain. Despite the high interest in genetics, our results show a remarkable underutilization of genetic services, with only 30% of families having visited a genetic service and 13% of patients having undergone the recommended genetic test. This poor service provision influenced recurrence risk perception and had a great impact on family planning. The National Health System should ensure their access to genetic services allowing them to take informed decisions with precise information.
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Affiliation(s)
- Marta Codina-Solà
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Institut Hospital del Mar d'Investigacions Mèdiques, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Av/Monforte de Lemos, 3-5, Pabellón 11, Planta 0, 28029, Madrid, Spain
| | - Luis A Pérez-Jurado
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Institut Hospital del Mar d'Investigacions Mèdiques, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Av/Monforte de Lemos, 3-5, Pabellón 11, Planta 0, 28029, Madrid, Spain
| | - Ivon Cuscó
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Institut Hospital del Mar d'Investigacions Mèdiques, C/Dr. Aiguader, 88, 08003, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Av/Monforte de Lemos, 3-5, Pabellón 11, Planta 0, 28029, Madrid, Spain
| | - Clara Serra-Juhé
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, C/Dr. Aiguader, 88, 08003, Barcelona, Spain. .,Institut Hospital del Mar d'Investigacions Mèdiques, C/Dr. Aiguader, 88, 08003, Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Raras, Av/Monforte de Lemos, 3-5, Pabellón 11, Planta 0, 28029, Madrid, Spain.
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11
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Churbanov A, Abrahamyan L. Preventing Common Hereditary Disorders through Time-Separated Twinning. BIONANOSCIENCE 2018. [DOI: 10.1007/s12668-017-0488-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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12
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Abstract
Examining sex differences in the brain has been historically contentious but is nonetheless important for advancing mental health for both girls and boys. Unfortunately, females in biomedical research remain underrepresented in most mental health conditions including autism spectrum disorders (ASD), even though equal inclusion of females would improve treatment for girls and yield benefits to boys. This review examines sex differences in the relationship between neuroanatomy and neurogenetics of ASD. Recent findings reveal that girls diagnosed with ASD exhibit more intellectual and behavioral problems compared to their male counterparts, suggesting that girls may be less likely diagnosed in the absence of such problems or that they require a higher mutational load to meet the diagnostic criteria. Thus far, the female biased effect of chromosome 4, 5p15.33, 8p, 9p24.1, 11p12-13, 15q, and Xp22.3 and the male biased effect of 1p31.3, 5q12.3, 7q, 9q33.3, 11q13.4, 13q33.3, 16p11.2, 17q11-21, Xp22.33/Yp11.31, DRD1, NLGN3, MAOA, and SHANK1 deletion have been discovered in ASD. The SNPs of genes such as RYR2, UPP2, and the androgen receptor gene have been shown to have sex-biasing factors in both girls and boys diagnosed with ASD. These sex-related genetic factors may drive sex differences in the neuroanatomy of these girls and boys, including abnormal enlargement in temporal gray and white matter volumes, and atypical reduction in cerebellar gray matter volumes and corpus callosum fibers projecting to the anterior frontal cortex in ASD girls relative to boys. Such factors may also be responsible for the attenuation of brain sexual differentiation in adult men and women with ASD; however, much remains to be uncovered or replicated. Future research should leverage further the association between neuroanatomy and genetics in girls for an integrated and interdisciplinary understanding of ASD.
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13
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Fakhoury M. Imaging genetics in autism spectrum disorders: Linking genetics and brain imaging in the pursuit of the underlying neurobiological mechanisms. Prog Neuropsychopharmacol Biol Psychiatry 2018; 80:101-114. [PMID: 28322981 DOI: 10.1016/j.pnpbp.2017.02.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/22/2017] [Accepted: 02/22/2017] [Indexed: 01/08/2023]
Abstract
Autism spectrum disorders (ASD) include a wide range of heterogeneous neurodevelopmental conditions that affect an individual in several aspects of social communication and behavior. Recent advances in molecular genetic technologies have dramatically increased our understanding of ASD etiology through the identification of several autism risk genes, most of which serve important functions in synaptic plasticity and protein synthesis. However, despite significant progress in this field of research, the characterization of the neurobiological mechanisms by which common genetic risk variants might operate to give rise to ASD symptomatology has proven to be far more difficult than expected. The imaging genetics approach holds great promise for advancing our understanding of ASD etiology by bridging the gap between genetic variations and their resultant biological effects on the brain. This paper provides a conceptual overview of the contribution of genetics in ASD and discusses key findings from the emerging field of imaging genetics.
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Affiliation(s)
- Marc Fakhoury
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3C 3J7, Canada.
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14
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Goodrich AJ, Volk HE, Tancredi DJ, McConnell R, Lurmann FW, Hansen RL, Schmidt RJ. Joint effects of prenatal air pollutant exposure and maternal folic acid supplementation on risk of autism spectrum disorder. Autism Res 2018; 11:69-80. [PMID: 29120534 PMCID: PMC5777535 DOI: 10.1002/aur.1885] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 06/27/2017] [Accepted: 09/24/2017] [Indexed: 12/14/2022]
Abstract
Independent studies report that periconceptional folic acid (FA) may decrease the risk of autism spectrum disorder (ASD) while exposure to air pollution may increase ASD risk. We examined the joint effects of gestational FA and air pollution exposures in association with ASD. We studied 346 ASD cases and 260 typically developing controls from the CHARGE case-control study. Self-reported FA intake for each month of pregnancy was quantified. Estimates of exposure to near roadway air pollution (NRP) and criteria air pollutant measures were assigned based on maternal residential history. Among mothers with high FA intake (>800 μg) in the first pregnancy month, exposure to increasing levels of all air pollutants, except ozone, during the first trimester was associated with decreased ASD risk, while increased ASD risk was observed for the same pollutant among mothers with low FA intake (≤800 μg). This difference was statistically significant for NO2 (e.g., NO2 and low FA intake: OR = 1.53 (0.91, 2.56) vs NO2 and high FA intake: OR = 0.74 (0.46, 1.19), P-interaction = 0.04). Mothers exposed to higher levels (≥ median) of any air pollutant during the first trimester of pregnancy and who reported low FA intake were at a higher ASD risk compared to mothers exposed to lower levels of that air pollutant and who reported high first month FA intake. Joint effects showed significant (alpha < 0.10) departures from expected interaction for NRP and NO2 . Our results suggest that periconceptional FA intake may reduce ASD risk in those with high prenatal air pollution exposure. Further study is needed to replicate these findings in larger sample sizes and to understand mechanisms of this potential relationship.. Autism Res 2018, 11: 69-80. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY We examined interactions between periconceptional folic acid (FA) and air pollution exposure on risk of ASD. Mothers exposed to higher levels of air pollution during the first trimester of pregnancy and who reported low supplemental FA intake during the first pregnancy month were at a higher ASD risk compared to mothers exposed to lower levels of air pollution and who reported high first month FA intake. Our results suggest that periconceptional FA intake may reduce ASD risk in those with high prenatal air pollution exposure.
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Affiliation(s)
- Amanda J Goodrich
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Heather E Volk
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Department of Mental Health, Wendy Klag Center for Autism and Developmental Disabilities, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD
| | - Daniel J Tancredi
- Department of Pediatrics, University of California Davis, Sacramento, CA
| | - Rob McConnell
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | | | - Robin L Hansen
- Department of Pediatrics, University of California Davis, Sacramento, CA
- MIND (Medical Investigation of Neurodevelopmental Disorders) Institute, University of California Davis, Davis, CA
| | - Rebecca J Schmidt
- MIND (Medical Investigation of Neurodevelopmental Disorders) Institute, University of California Davis, Davis, CA
- Department of Public Health Sciences, University of California Davis, Davis, CA
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15
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Lomas Mevers JE, Call NA, Miller SJ. Practice Recommendations for Addressing Problem Behaviors in Siblings with Autism Spectrum Disorder. Behav Anal Pract 2017; 10:363-374. [PMID: 29214132 DOI: 10.1007/s40617-017-0190-z] [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: 10/19/2022] Open
Abstract
Children with autism spectrum disorder (ASD) display an increased prevalence of problem behavior, relative to the typically developing population. Given the heritability of ASD and its growing prevalence, clinicians who implement behavioral treatments are likely to encounter families with siblings with ASD who exhibit problem behavior. Thus, there is a need for guidance for treatment of problem behavior for these families. This paper presents strategies for conducting behavioral assessments, developing treatments for problem behaviors, caregiver training, and generalization strategies when there are multiple affected children in one family. A case study is presented to illustrate the key clinical decisions made to increase the likelihood of a successful treatment outcome for these families.
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Affiliation(s)
- Joanna E Lomas Mevers
- Marcus Autism Center, Children's Healthcare of Atlanta, 1920 Briarcliff Rd, Atlanta, GA 30329 USA.,Division of Autism & Related Disabilities, Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
| | - Nathan A Call
- Marcus Autism Center, Children's Healthcare of Atlanta, 1920 Briarcliff Rd, Atlanta, GA 30329 USA.,Division of Autism & Related Disabilities, Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
| | - Sarah J Miller
- Marcus Autism Center, Children's Healthcare of Atlanta, 1920 Briarcliff Rd, Atlanta, GA 30329 USA.,Division of Autism & Related Disabilities, Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
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16
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Osório AAC, do Egito JHT, Martins GC, Kim CA, Honjo RS, Sampaio ADCS, Mesquita ARM, Macedo EC, Boggio PS, Teixeira MCTV. Associations between fetal testosterone and pro-social tendencies, anxiety and autistic symptoms in Williams syndrome: a preliminary study. INTERNATIONAL JOURNAL OF DEVELOPMENTAL DISABILITIES 2017; 65:82-88. [PMID: 34141327 PMCID: PMC8115471 DOI: 10.1080/20473869.2017.1376163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Objective: Fetal testosterone (fT) has organizational effects on the developing human nervous system and can be reliably estimated by the ratio between the length of the second and fourth digits - 2D:4D. Previous studies reported altered patterns of fT in some developmental disabilities (e.g. ASD) relative to typically developing individuals (TD). Williams syndrome (WS) is a rare genetic disorder characterized by exacerbated empathy and social approach and heightened anxiety. Recent reports also highlight the co-occurrence of significant levels of autistic symptoms. Despite constituting an interesting model to study androgenic contributions to social behavior, no studies have sought to explore fT in WS. The main aims of this preliminary study were two-fold: (a) to compare 2D:4D in WS and TD; (b) to analyze the pattern of associations between 2D:4D and hypersociability, affective and cognitive empathy, anxiety and autistic symptoms in WS. Methods: 2D:4D were measured from digital scans of the ventral surface of the right hand. Hypersociability, empathy, anxiety and autistic symptoms were obtained from parental reports. Results: There were no significant differences in 2D:4D between WS than TD. In WS lower fT (higher 2D:4D) was significantly associated with hypersociability and affective empathy, as well as marginally associated with anxiety/depression scores. In contrast, cognitive empathy was marginally and negatively associated with 2D:4D, while levels of autistic symptoms were unrelated with this measure. Conclusion: Our results suggest that fT may be implicated in the emergence of several cardinal features of WS, namely hypersociability, affective empathy and anxiety, but not in ASD symptoms.
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Affiliation(s)
- Ana Alexandra Caldas Osório
- Social and Cognitive Neuroscience Laboratory, Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil
| | - Júlia Horta Tabosa do Egito
- Social and Cognitive Neuroscience Laboratory, Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil
| | - Gabriela Carneiro Martins
- Social and Cognitive Neuroscience Laboratory, Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil
| | - Chong Ae Kim
- Instituto da Criança, Faculdade de Medicina da, Universidade de São Paulo, São Paulo, Brazil
| | - Rachel Sayuri Honjo
- Instituto da Criança, Faculdade de Medicina da, Universidade de São Paulo, São Paulo, Brazil
| | | | | | - Elizeu Coutinho Macedo
- Social and Cognitive Neuroscience Laboratory, Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil
| | - Paulo Sérgio Boggio
- Social and Cognitive Neuroscience Laboratory, Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil
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17
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Increased Sensory Processing Atypicalities in Parents of Multiplex ASD Families Versus Typically Developing and Simplex ASD Families. J Autism Dev Disord 2017; 47:535-548. [PMID: 27538965 PMCID: PMC5352777 DOI: 10.1007/s10803-016-2888-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Recent studies have suggested that sensory processing atypicalities may share genetic influences with autism spectrum disorder (ASD). To further investigate this, the adolescent/adult sensory profile (AASP) questionnaire was distributed to 85 parents of typically developing children (P-TD), 121 parents from simplex ASD families (SPX), and 54 parents from multiplex ASD families (MPX). After controlling for gender and presence of mental disorders, results showed that MPX parents significantly differed from P-TD parents in all four subscales of the AASP. Differences between SPX and MPX parents reached significance in the Sensory Sensitivity subscale and also in subsequent modality-specific analyses in the auditory and visual domains. Our finding that parents with high genetic liability for ASD (i.e., MPX) had more sensory processing atypicalities than parents with low (i.e., SPX) or no (i.e., P-TD) ASD genetic liability suggests that sensory processing atypicalities may contribute to the genetic susceptibility for ASD.
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18
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Klein M, van Donkelaar M, Verhoef E, Franke B. Imaging genetics in neurodevelopmental psychopathology. Am J Med Genet B Neuropsychiatr Genet 2017; 174:485-537. [PMID: 29984470 PMCID: PMC7170264 DOI: 10.1002/ajmg.b.32542] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 02/02/2017] [Accepted: 03/10/2017] [Indexed: 01/27/2023]
Abstract
Neurodevelopmental disorders are defined by highly heritable problems during development and brain growth. Attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), and intellectual disability (ID) are frequent neurodevelopmental disorders, with common comorbidity among them. Imaging genetics studies on the role of disease-linked genetic variants on brain structure and function have been performed to unravel the etiology of these disorders. Here, we reviewed imaging genetics literature on these disorders attempting to understand the mechanisms of individual disorders and their clinical overlap. For ADHD and ASD, we selected replicated candidate genes implicated through common genetic variants. For ID, which is mainly caused by rare variants, we included genes for relatively frequent forms of ID occurring comorbid with ADHD or ASD. We reviewed case-control studies and studies of risk variants in healthy individuals. Imaging genetics studies for ADHD were retrieved for SLC6A3/DAT1, DRD2, DRD4, NOS1, and SLC6A4/5HTT. For ASD, studies on CNTNAP2, MET, OXTR, and SLC6A4/5HTT were found. For ID, we reviewed the genes FMR1, TSC1 and TSC2, NF1, and MECP2. Alterations in brain volume, activity, and connectivity were observed. Several findings were consistent across studies, implicating, for example, SLC6A4/5HTT in brain activation and functional connectivity related to emotion regulation. However, many studies had small sample sizes, and hypothesis-based, brain region-specific studies were common. Results from available studies confirm that imaging genetics can provide insight into the link between genes, disease-related behavior, and the brain. However, the field is still in its early stages, and conclusions about shared mechanisms cannot yet be drawn.
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Affiliation(s)
- Marieke Klein
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Marjolein van Donkelaar
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Ellen Verhoef
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Barbara Franke
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
- Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
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19
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Ansen-Wilson LJ, Lipinski RJ. Gene-environment interactions in cortical interneuron development and dysfunction: A review of preclinical studies. Neurotoxicology 2017; 58:120-129. [PMID: 27932026 PMCID: PMC5328258 DOI: 10.1016/j.neuro.2016.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 12/03/2016] [Accepted: 12/03/2016] [Indexed: 12/26/2022]
Abstract
Cortical interneurons (cINs) are a diverse group of locally projecting neurons essential to the organization and regulation of neural networks. Though they comprise only ∼20% of neurons in the neocortex, their dynamic modulation of cortical activity is requisite for normal cognition and underlies multiple aspects of learning and memory. While displaying significant morphological, molecular, and electrophysiological variability, cINs collectively function to maintain the excitatory-inhibitory balance in the cortex by dampening hyperexcitability and synchronizing activity of projection neurons, primarily through use of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Disruption of the excitatory-inhibitory balance is a common pathophysiological feature of multiple seizure and neuropsychiatric disorders, including epilepsy, schizophrenia, and autism. While most studies have focused on genetic disruption of cIN development in these conditions, emerging evidence indicates that cIN development is exquisitely sensitive to teratogenic disruption. Here, we review key aspects of cIN development, including specification, migration, and integration into neural circuits. Additionally, we examine the mechanisms by which prenatal exposure to common chemical and environmental agents disrupt these events in preclinical models. Understanding how genetic and environmental factors interact to disrupt cIN development and function has tremendous potential to advance prevention and treatment of prevalent seizure and neuropsychiatric illnesses.
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Affiliation(s)
- Lydia J Ansen-Wilson
- Department of Comparative Biosciences School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI, 53706, USA; Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI, 53706, USA.
| | - Robert J Lipinski
- Department of Comparative Biosciences School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI, 53706, USA; Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI, 53706, USA; Molecular and Environmental Toxicology Center, School of Medicine and Public Health, University of Wisconsin-Madison, 1010B McArdle Building, 1400 University Avenue, Madison, WI, 53706, USA.
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20
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Abstract
Despite the progress made in understanding the biology of autism spectrum disorder (ASD), effective biological interventions for the core symptoms remain elusive. Because of the etiological heterogeneity of ASD, identification of a "one-size-fits-all" treatment approach will likely continue to be challenging. A meeting was convened at the University of Missouri and the Thompson Center to discuss strategies for stratifying patients with ASD for the purpose of moving toward precision medicine. The "white paper" presented here articulates the challenges involved and provides suggestions for future solutions.
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21
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Landry O, Chouinard PA. Why We Should Study the Broader Autism Phenotype in Typically Developing Populations. JOURNAL OF COGNITION AND DEVELOPMENT 2016. [DOI: 10.1080/15248372.2016.1200046] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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22
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Environmental Enrichment Therapy for Autism: Outcomes with Increased Access. Neural Plast 2016; 2016:2734915. [PMID: 27721995 PMCID: PMC5046013 DOI: 10.1155/2016/2734915] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/20/2016] [Accepted: 08/23/2016] [Indexed: 01/24/2023] Open
Abstract
We have previously shown in two randomized clinical trials that environmental enrichment is capable of ameliorating symptoms of autism spectrum disorder (ASD), and in the present study, we determined whether this therapy could be effective under real-world circumstances. 1,002 children were given daily Sensory Enrichment Therapy, by their parents, using personalized therapy instructions given over the Internet. Parents were asked to assess the symptoms of their child every 2 weeks for up to 7 months. An intention-to-treat analysis showed significant overall gains for a wide range of symptoms in these children, including learning, memory, anxiety, attention span, motor skills, eating, sleeping, sensory processing, self-awareness, communication, social skills, and mood/autism behaviors. The children of compliant caregivers were more likely to experience a significant improvement in their symptoms. The treatment was effective across a wide age range and there was equal progress reported for males and females, for USA and international subjects, for those who paid and those who did not pay for the therapy, and for individuals at all levels of initial symptom severity. Environmental enrichment, delivered via an online system, therefore appears to be an effective, low-cost means of treating the symptoms of ASD.
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23
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Neysmith-Roy JM. The Tomatis Method with Severely Autistic Boys: Individual Case Studies of Behavioral Changes. SOUTH AFRICAN JOURNAL OF PSYCHOLOGY 2016. [DOI: 10.1177/008124630103100105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Six severely autistic males ranging in age from 4 years to 11 years received the Tomatis Method to assist in alleviating the severity of behaviours contributing to the diagnosis of autism. Ten minute video samples were taken of each boy, under two conditions of play, every time he completed one section of the treatment programme. As measured by the Children's Autism Rating Scale (CARS) all of the boys were severely autistic at the beginning of treatment. Three (50%) of the boys demonstrated positive behavioural changes by the end of the treatment. One boy was no longer considered to be autistic, two boys showed mild symptoms of autism and three boys remained within the severely autistic range. Of particular interest were the changes that occurred in pre-linguistic areas for five of the six boys. These included Adaptation to Change, Listening Response, Non Verbal Communication, Emotional Response and Activity Level. These behaviours are considered prerequisites for successful verbal communication. The children who demonstrated behavioural change were 6 years of age or younger at the beginning of treatment. The author suggests that the Tomatis Method may be helpful in making prelinguistic behaviours manageable and thus help prepare the child to learn basic skills necessary for the development of language and learning.
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24
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Clarke AM, Clarke ADB. The Adult Outcome of Early Behavioural Abnormalities. INTERNATIONAL JOURNAL OF BEHAVIORAL DEVELOPMENT 2016. [DOI: 10.1177/016502548801100102] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Greater constancies across time are to be expected in seriously deviant conditions compared with less abnormal development. Selective reviews are offered on adult outcomes of severe mental retardation, autism, conduct disorders, mild retardation and adjustment disorders of childhood. In the first category, a highly dependent life path is inevitable. For autism there is a small "escape rate". With conduct disorders, around half have a very poor outcome. An important prospective study of mild retardation, supported by other findings, indicated that two-thirds of those who were administratively classified as retarded in childhood, were as young adults, no longer in need of special services. Finally, adjustment disorders of childhood only rarely show continuities into adult life. Each category is heterogeneous in aetiology, and multifactorial influences commonly operate in individual cases. The presence of an organic component appears to narrow the range of reaction between constitution and environment. It seems probable that, with increasingly common social and familial disruptions, conduct disorders, mild retardation and adjustment problems will become increasingly prevalent, whereas biomedical advances are likely to reduce the incidence of severe retardation.
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25
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Abstract
International school psychologists play an important professional role in providing early diagnostic, consultative and treatment-planning services for autistic children and their families. Recent advances in our understanding of this complex disorder necessitates updating professionals in the etiology and treatment of autism. The article describes components of making a differential diagnosis of autism from developmental language/speech disorders, mental retardation and schizophrenia. Etiological theories based on recent neurobiological data are outlined and the psychometric properties of cognitive ability and behavioral rating instruments frequently used with this population are delineated. Specific innovative educational and pharmacological treatment approaches are reviewed.
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26
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Abstract
Early infantile autism is the most severe of a group of neurodevelopmental syndromes called the pervasive developmental disorders. The clinical features of autism vary greatly, but, by definition, include deficits in social relatedness, communication, and interests or routines. The onset of autistic signs and behaviors typ ically occurs in infancy, and the syndrome is usually fully present by the fourth year. The presence of mental retardation affects the clinical picture greatly. Severely autistic children may be retarded and mute and are often preoccupied with repetitive activities; they often exhibit motor stereotypes, such as rocking or hand flapping. They can be profoundly withdrawn and may show extreme aversion to social or physical contact. More mildly affected children may have normal or even superior intelligence, with well-developed language skills. Their deficits in social relatedness and preoccupation with rituals and routines may set them apart as very odd, but not necessarily as autistic. Autism occurs in 1 of 2000 live births; boys outnumber girls about 3 or 4:1. Although there are no localizing neurological signs in autism, mild or "soft" neurological signs are common and grand mal seizures are frequently present after puberty (Lotspeich LJ, Ciaranello RD. The neurobiology and genetics of infantile autism. In: Bradley R, editor. International reviews of neurobiology. San Diego: Academic Press 1993:87-129). The Neuroscientist 1:361-367, 1995
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Affiliation(s)
- Andrea L. Ciaranello
- Harvard University (ALC) Cambridge, Massachussets Nancy
Pritzker Laboratory of Developmental and Molecular Neurobiology (RDC) Department
of Psychiatry Stanford University School of Medicine Stanford, California
| | - Roland D. Ciaranello
- Harvard University (ALC) Cambridge, Massachussets Nancy
Pritzker Laboratory of Developmental and Molecular Neurobiology (RDC) Department
of Psychiatry Stanford University School of Medicine Stanford, California
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27
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Noroozi R, Taheri M, Movafagh A, Mirfakhraie R, Solgi G, Sayad A, Mazdeh M, Darvish H. Glutamate receptor, metabotropic 7 (GRM7) gene variations and susceptibility to autism: A case-control study. Autism Res 2016; 9:1161-1168. [DOI: 10.1002/aur.1640] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 04/04/2016] [Indexed: 12/29/2022]
Affiliation(s)
- Rezvan Noroozi
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Mohammad Taheri
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Abolfazl Movafagh
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Reza Mirfakhraie
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Ghasem Solgi
- Department of Immunology, School of Medicine; Hamadan University of Medical Sciences; Hamadan Iran
| | - Arezou Sayad
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Mehrdokht Mazdeh
- Department of Neurology, School of Medicine; Hamadan University of Medical Sciences; Hamadan Iran
| | - Hossein Darvish
- From the Department of Medical Genetics, Faculty of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
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28
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Abstract
Autism spectrum disorder (ASD) is a devastating neurodevelopmental disorder with high prevalence in the population and a pronounced male preponderance. ASD has a strong genetic basis, but until recently, a large fraction of the genetic factors contributing to liability was still unknown. Over the past 3 years, high-throughput next-generation sequencing on large cohorts has exposed a heterogeneous and complex genetic landscape and has revealed novel risk genes. Here, we provide an overview of the recent advances on the ASD genetic architecture, with an emphasis on the estimates of heritability, the contribution of common variants, and the role of inherited and de novo rare variation. We also examine the genetic components of the reported gender bias. Finally, we discuss the emerging findings from sequencing studies and how they illuminate crucial aspects of ASD pathophysiology.
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Affiliation(s)
- Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, USA
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29
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Tick B, Bolton P, Happé F, Rutter M, Rijsdijk F. Heritability of autism spectrum disorders: a meta-analysis of twin studies. J Child Psychol Psychiatry 2016; 57:585-95. [PMID: 26709141 PMCID: PMC4996332 DOI: 10.1111/jcpp.12499] [Citation(s) in RCA: 494] [Impact Index Per Article: 61.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/27/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND The etiology of Autism Spectrum Disorder (ASD) has been recently debated due to emerging findings on the importance of shared environmental influences. However, two recent twin studies do not support this and instead re-affirm strong genetic effects on the liability to ASD, a finding consistent with previous reports. This study conducts a systematic review and meta-analysis of all twin studies of ASD published to date and explores the etiology along the continuum of a quantitative measure of ASD. METHODS A PubMed Central, Science Direct, Google Scholar, Web of Knowledge structured search conducted online, to identify all twin studies on ASD published to date. Thirteen primary twin studies were identified, seven were included in the meta-analysis by meeting Systematic Recruitment criterion; correction for selection and ascertainment strategies, and applied prevalences were assessed for these studies. In addition, a quantile DF extremes analysis was carried out on Childhood Autism Spectrum Test scores measured in a population sample of 6,413 twin pairs including affected twins. RESULTS The meta-analysis correlations for monozygotic twins (MZ) were almost perfect at .98 (95% Confidence Interval, .96-.99). The dizygotic (DZ) correlation, however, was .53 (95% CI .44-.60) when ASD prevalence rate was set at 5% (in line with the Broad Phenotype of ASD) and increased to .67 (95% CI .61-.72) when applying a prevalence rate of 1%. The meta-analytic heritability estimates were substantial: 64-91%. Shared environmental effects became significant as the prevalence rate decreased from 5-1%: 07-35%. The DF analyses show that for the most part, there is no departure from linearity in heritability. CONCLUSIONS We demonstrate that: (a) ASD is due to strong genetic effects; (b) shared environmental effects become significant as a function of lower prevalence rate; (c) previously reported significant shared environmental influences are likely a statistical artefact of overinclusion of concordant DZ twins.
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Affiliation(s)
- Beata Tick
- MRC Social, Genetic and Developmental Psychiatry CentreIOPPNKing's College LondonLondonUK
| | - Patrick Bolton
- MRC Social, Genetic and Developmental Psychiatry CentreIOPPNKing's College LondonLondonUK
| | - Francesca Happé
- MRC Social, Genetic and Developmental Psychiatry CentreIOPPNKing's College LondonLondonUK
| | - Michael Rutter
- MRC Social, Genetic and Developmental Psychiatry CentreIOPPNKing's College LondonLondonUK
| | - Frühling Rijsdijk
- MRC Social, Genetic and Developmental Psychiatry CentreIOPPNKing's College LondonLondonUK
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30
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Husarova VM, Lakatosova S, Pivovarciova A, Babinska K, Bakos J, Durdiakova J, Kubranska A, Ondrejka I, Ostatnikova D. Plasma Oxytocin in Children with Autism and Its Correlations with Behavioral Parameters in Children and Parents. Psychiatry Investig 2016; 13:174-83. [PMID: 27081377 PMCID: PMC4823192 DOI: 10.4306/pi.2016.13.2.174] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 05/08/2015] [Accepted: 06/04/2015] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE Oxytocin (OT) has been implicated to play an important role in autism spectrum disorders (ASD) etiology. We aimed to find out the differences in plasma OT levels between children with autism and healthy children, the associations of OT levels with particular autism symptoms and the associations of particular parental autistic traits with their ASD children OT levels. METHODS We included 19 boys with autism and 44 healthy age-matched boys. OT levels were analyzed by ELISA method. Children with autism were scored by Childhood Autism Rating Scale and Autism Diagnostic Interview (ADI), adjusted research version. Autism Spectrum Quotient (AQ), Systemizing Quotient (SQ) and Empathizing Quotient were completed by parents of children with autism. RESULTS Children with autism had significantly lower plasma OT levels than controls. OT levels positively correlated with ADI Reciprocal Interaction and Communication scores. AQ and SQ of fathers positively correlated with children plasma OT level. CONCLUSION Our results support the hypothesis of OT deficiency in autism. The "paradoxical" associations of OT levels and social skills in children with autism indicate disturbances at various levels of OT system. We first reported associations of OT levels in children with autism and behavioral measures in fathers indicating that OT abnormalities stay between parental autistic traits and autism symptoms in their children.
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Affiliation(s)
- Veronika Marcincakova Husarova
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
- Clinic of Psychiatry, Martin University Hospital and Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia
| | - Silvia Lakatosova
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Anna Pivovarciova
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Katarina Babinska
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Jan Bakos
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Jaroslava Durdiakova
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Aneta Kubranska
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
| | - Igor Ondrejka
- Clinic of Psychiatry, Martin University Hospital and Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia
| | - Daniela Ostatnikova
- Institute of Physiology, Medical Faculty Comenius University, Bratislava, Slovakia
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Kazdoba TM, Leach PT, Crawley JN. Behavioral phenotypes of genetic mouse models of autism. GENES, BRAIN, AND BEHAVIOR 2016; 15:7-26. [PMID: 26403076 PMCID: PMC4775274 DOI: 10.1111/gbb.12256] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/27/2015] [Accepted: 09/18/2015] [Indexed: 12/11/2022]
Abstract
More than a hundred de novo single gene mutations and copy-number variants have been implicated in autism, each occurring in a small subset of cases. Mutant mouse models with syntenic mutations offer research tools to gain an understanding of the role of each gene in modulating biological and behavioral phenotypes relevant to autism. Knockout, knockin and transgenic mice incorporating risk gene mutations detected in autism spectrum disorder and comorbid neurodevelopmental disorders are now widely available. At present, autism spectrum disorder is diagnosed solely by behavioral criteria. We developed a constellation of mouse behavioral assays designed to maximize face validity to the types of social deficits and repetitive behaviors that are central to an autism diagnosis. Mouse behavioral assays for associated symptoms of autism, which include cognitive inflexibility, anxiety, hyperactivity, and unusual reactivity to sensory stimuli, are frequently included in the phenotypic analyses. Over the past 10 years, we and many other laboratories around the world have employed these and additional behavioral tests to phenotype a large number of mutant mouse models of autism. In this review, we highlight mouse models with mutations in genes that have been identified as risk genes for autism, which work through synaptic mechanisms and through the mTOR signaling pathway. Robust, replicated autism-relevant behavioral outcomes in a genetic mouse model lend credence to a causal role for specific gene contributions and downstream biological mechanisms in the etiology of autism.
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Affiliation(s)
- T. M. Kazdoba
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - P. T. Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - J. N. Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
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Kazdoba TM, Leach PT, Yang M, Silverman JL, Solomon M, Crawley JN. Translational Mouse Models of Autism: Advancing Toward Pharmacological Therapeutics. Curr Top Behav Neurosci 2016; 28:1-52. [PMID: 27305922 PMCID: PMC5116923 DOI: 10.1007/7854_2015_5003] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Animal models provide preclinical tools to investigate the causal role of genetic mutations and environmental factors in the etiology of autism spectrum disorder (ASD). Knockout and humanized knock-in mice, and more recently knockout rats, have been generated for many of the de novo single gene mutations and copy number variants (CNVs) detected in ASD and comorbid neurodevelopmental disorders. Mouse models incorporating genetic and environmental manipulations have been employed for preclinical testing of hypothesis-driven pharmacological targets, to begin to develop treatments for the diagnostic and associated symptoms of autism. In this review, we summarize rodent behavioral assays relevant to the core features of autism, preclinical and clinical evaluations of pharmacological interventions, and strategies to improve the translational value of rodent models of autism.
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Affiliation(s)
- Tatiana M Kazdoba
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - Prescott T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - Mu Yang
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - Jill L Silverman
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - Marjorie Solomon
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA
| | - Jacqueline N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Room 1001A Research 2 Building 96, 4625 2nd Avenue, Sacramento, CA 95817, USA.
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Huguet G, Benabou M, Bourgeron T. The Genetics of Autism Spectrum Disorders. RESEARCH AND PERSPECTIVES IN ENDOCRINE INTERACTIONS 2016. [DOI: 10.1007/978-3-319-27069-2_11] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Giarelli E, Reiff M. Mothers' appreciation of chromosomal microarray analysis for autism spectrum disorder. J SPEC PEDIATR NURS 2015; 20:244-58. [PMID: 26112659 DOI: 10.1111/jspn.12121] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 05/06/2015] [Accepted: 05/11/2015] [Indexed: 01/08/2023]
Abstract
PURPOSE The aim of this study was to examine mothers' experiences with chromosomal microarray analysis (CMA) for a child with autism spectrum disorder (ASD). DESIGN AND METHODS This is a descriptive qualitative study using thematic content analysis of in-depth interview with 48 mothers of children who had genetic testing for ASD. RESULTS The principal theme, "something is missing," included missing knowledge about genetics, information on use of the results, explanations of the relevance to the diagnosis, and relevance to life-long care. Two subordinate themes were (a) disappreciation of the helpfulness of scientific information to explain the diagnosis, and (b) returning to personal experience for interpretation. PRACTICE IMPLICATIONS The test "appreciated" in value when results could be linked to the phenotype.
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Affiliation(s)
- Ellen Giarelli
- College of Nursing and Health Professions, Doctoral Nursing Program, Drexel University
| | - Marian Reiff
- Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Abstract
Over 70 years since the first description of the disease, disrupted social behavior remains a core clinical feature of autistic spectrum disorder. The complex etiology of the disorder portends the need for a better understanding of the brain mechanisms that enable social behaviors, particularly those that are relevant to autism which is characterized by a failure to develop peer relationships, difficulty with emotional reciprocity and imitative play, and disrupted language and communication skills. Toward this end, the current review will examine recent progress that has been made toward understanding the neural mechanisms underlying consociate social attachments.
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Affiliation(s)
- Gül Dölen
- a Department of Neuroscience, Brain Science Institute, Wendy Klag Center for Autism and Developmental Disabilities , Johns Hopkins University , Baltimore , MD , USA
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36
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Hua R, Wei M, Zhang C. The complex genetics in autism spectrum disorders. SCIENCE CHINA-LIFE SCIENCES 2015; 58:933-45. [PMID: 26335739 DOI: 10.1007/s11427-015-4893-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Autism spectrum disorders (ASD) are a pervasive neurodevelopmental disease characterized by deficits in social interaction and nonverbal communication, as well as restricted interests and stereotypical behavior. Genetic changes/heritability is one of the major contributing factors, and hundreds to thousands of causative and susceptible genes, copy number variants (CNVs), linkage regions, and microRNAs have been associated with ASD which clearly indicates that ASD is a complex genetic disorder. Here, we will briefly summarize some of the high-confidence genetic changes in ASD and their possible roles in their pathogenesis.
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Affiliation(s)
- Rui Hua
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - MengPing Wei
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Chen Zhang
- State Key Laboratory of Membrane Biology, School of Life Sciences; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
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De Rubeis S, Buxbaum JD. Genetics and genomics of autism spectrum disorder: embracing complexity. Hum Mol Genet 2015; 24:R24-31. [PMID: 26188008 DOI: 10.1093/hmg/ddv273] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 07/09/2015] [Indexed: 01/19/2023] Open
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) characterized by impairments in social communication and social interaction and the presence of repetitive behaviors and/or restricted interests. ASD has profound etiological and clinical heterogeneity, which has impeded the identification of risk factors and pathophysiological processes underlying the disorder. A constellation of (i) types of genetic variation, (ii) modes of inheritance and (iii) specific genomic loci and genes have all recently been implicated in ASD risk, and these findings are currently being extended with functional analyses in model organisms and genotype-phenotype correlation studies. The overlap of risk loci between ASD and other NDDs raises intriguing questions around the mechanisms of risk. In this review, we will touch upon these aspects of ASD and how they might be addressed.
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Affiliation(s)
- Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA Department of Psychiatry, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA
| | - Joseph D Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA Department of Psychiatry, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA Department of Neuroscience, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA and The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, NY 10029, USA
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Griswold AJ, Dueker ND, Van Booven D, Rantus JA, Jaworski JM, Slifer SH, Schmidt MA, Hulme W, Konidari I, Whitehead PL, Cuccaro ML, Martin ER, Haines JL, Gilbert JR, Hussman JP, Pericak-Vance MA. Targeted massively parallel sequencing of autism spectrum disorder-associated genes in a case control cohort reveals rare loss-of-function risk variants. Mol Autism 2015; 6:43. [PMID: 26185613 PMCID: PMC4504419 DOI: 10.1186/s13229-015-0034-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 06/16/2015] [Indexed: 12/31/2022] Open
Abstract
Background Autism spectrum disorder (ASD) is highly heritable, yet genome-wide association studies (GWAS), copy number variation screens, and candidate gene association studies have found no single factor accounting for a large percentage of genetic risk. ASD trio exome sequencing studies have revealed genes with recurrent de novo loss-of-function variants as strong risk factors, but there are relatively few recurrently affected genes while as many as 1000 genes are predicted to play a role. As such, it is critical to identify the remaining rare and low-frequency variants contributing to ASD. Methods We have utilized an approach of prioritization of genes by GWAS and follow-up with massively parallel sequencing in a case-control cohort. Using a previously reported ASD noise reduction GWAS analyses, we prioritized 837 RefSeq genes for custom targeting and sequencing. We sequenced the coding regions of those genes in 2071 ASD cases and 904 controls of European white ancestry. We applied comprehensive annotation to identify single variants which could confer ASD risk and also gene-based association analysis to identify sets of rare variants associated with ASD. Results We identified a significant over-representation of rare loss-of-function variants in genes previously associated with ASD, including a de novo premature stop variant in the well-established ASD candidate gene RBFOX1. Furthermore, ASD cases were more likely to have two damaging missense variants in candidate genes than controls. Finally, gene-based rare variant association implicates genes functioning in excitatory neurotransmission and neurite outgrowth and guidance pathways including CACNAD2, KCNH7, and NRXN1. Conclusions We find suggestive evidence that rare variants in synaptic genes are associated with ASD and that loss-of-function mutations in ASD candidate genes are a major risk factor, and we implicate damaging mutations in glutamate signaling receptors and neuronal adhesion and guidance molecules. Furthermore, the role of de novo mutations in ASD remains to be fully investigated as we identified the first reported protein-truncating variant in RBFOX1 in ASD. Overall, this work, combined with others in the field, suggests a convergence of genes and molecular pathways underlying ASD etiology. Electronic supplementary material The online version of this article (doi:10.1186/s13229-015-0034-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anthony J Griswold
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Nicole D Dueker
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Derek Van Booven
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Joseph A Rantus
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - James M Jaworski
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Susan H Slifer
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Michael A Schmidt
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - William Hulme
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Ioanna Konidari
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Patrice L Whitehead
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Michael L Cuccaro
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA ; Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Eden R Martin
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA ; Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Jonathan L Haines
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH 44106 USA
| | - John R Gilbert
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA ; Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | | | - Margaret A Pericak-Vance
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA ; Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
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Jaiswal P, Mohanakumar KP, Rajamma U. Serotonin mediated immunoregulation and neural functions: Complicity in the aetiology of autism spectrum disorders. Neurosci Biobehav Rev 2015; 55:413-31. [PMID: 26021727 DOI: 10.1016/j.neubiorev.2015.05.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/11/2015] [Accepted: 05/12/2015] [Indexed: 12/19/2022]
Abstract
Serotonergic system has long been implicated in the aetiology of autism spectrum disorders (ASD), since platelet hyperserotonemia is consistently observed in a subset of autistic patients, who respond well to selective serotonin reuptake inhibitors. Apart from being a neurotransmitter, serotonin functions as a neurotrophic factor directing brain development and as an immunoregulator modulating immune responses. Serotonin transporter (SERT) regulates serotonin level in lymphoid tissues to ensure its proper functioning in innate and adaptive responses. Immunological molecules such as cytokines in turn regulate the transcription and activity of SERT. Dysregulation of serotonergic system could trigger signalling cascades that affect normal neural-immune interactions culminating in neurodevelopmental and neural connectivity defects precipitating behavioural abnormalities, or the disease phenotypes. Therefore, we suggest that a better understanding of the cross talk between serotonergic genes, immune systems and serotonergic neurotransmission will open wider avenues to develop pharmacological leads for addressing the core ASD behavioural deficits.
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Affiliation(s)
- Preeti Jaiswal
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector-J, EM Bypass, Kolkata 700 107, India
| | - Kochupurackal P Mohanakumar
- Division of Cell Biology & Physiology, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700 032, India
| | - Usha Rajamma
- Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, 482 Madudah, Plot I-24, Sector-J, EM Bypass, Kolkata 700 107, India.
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40
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Colvert E, Tick B, McEwen F, Stewart C, Curran SR, Woodhouse E, Gillan N, Hallett V, Lietz S, Garnett T, Ronald A, Plomin R, Rijsdijk F, Happé F, Bolton P. Heritability of Autism Spectrum Disorder in a UK Population-Based Twin Sample. JAMA Psychiatry 2015; 72:415-23. [PMID: 25738232 PMCID: PMC4724890 DOI: 10.1001/jamapsychiatry.2014.3028] [Citation(s) in RCA: 266] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
IMPORTANCE Most evidence to date highlights the importance of genetic influences on the liability to autism and related traits. However, most of these findings are derived from clinically ascertained samples, possibly missing individuals with subtler manifestations, and obtained estimates may not be representative of the population. OBJECTIVES To establish the relative contributions of genetic and environmental factors in liability to autism spectrum disorder (ASD) and a broader autism phenotype in a large population-based twin sample and to ascertain the genetic/environmental relationship between dimensional trait measures and categorical diagnostic constructs of ASD. DESIGN, SETTING, AND PARTICIPANTS We used data from the population-based cohort Twins Early Development Study, which included all twin pairs born in England and Wales from January 1, 1994, through December 31, 1996. We performed joint continuous-ordinal liability threshold model fitting using the full information maximum likelihood method to estimate genetic and environmental parameters of covariance. Twin pairs underwent the following assessments: the Childhood Autism Spectrum Test (CAST) (6423 pairs; mean age, 7.9 years), the Development and Well-being Assessment (DAWBA) (359 pairs; mean age, 10.3 years), the Autism Diagnostic Observation Schedule (ADOS) (203 pairs; mean age, 13.2 years), the Autism Diagnostic Interview-Revised (ADI-R) (205 pairs; mean age, 13.2 years), and a best-estimate diagnosis (207 pairs). MAIN OUTCOMES AND MEASURES Participants underwent screening using a population-based measure of autistic traits (CAST assessment), structured diagnostic assessments (DAWBA, ADI-R, and ADOS), and a best-estimate diagnosis. RESULTS On all ASD measures, correlations among monozygotic twins (range, 0.77-0.99) were significantly higher than those for dizygotic twins (range, 0.22-0.65), giving heritability estimates of 56% to 95%. The covariance of CAST and ASD diagnostic status (DAWBA, ADOS and best-estimate diagnosis) was largely explained by additive genetic factors (76%-95%). For the ADI-R only, shared environmental influences were significant (30% [95% CI, 8%-47%]) but smaller than genetic influences (56% [95% CI, 37%-82%]). CONCLUSIONS AND RELEVANCE The liability to ASD and a more broadly defined high-level autism trait phenotype in this large population-based twin sample derives primarily from additive genetic and, to a lesser extent, nonshared environmental effects. The largely consistent results across different diagnostic tools suggest that the results are generalizable across multiple measures and assessment methods. Genetic factors underpinning individual differences in autismlike traits show considerable overlap with genetic influences on diagnosed ASD.
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Affiliation(s)
- Emma Colvert
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Beata Tick
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Fiona McEwen
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England2Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology, and Neuroscience, K
| | - Catherine Stewart
- South London and Maudsley NHS (National Health Service) Foundation Trust, Maudsley Hospital, London, England4Department of Psychology, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Sarah R. Curran
- Department of Psychology, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England5Brighton and Sussex Medical School, University of Sussex, East Sussex, England6Sussex Partnership NHS Foundation Trust, Trust Headquart
| | - Emma Woodhouse
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Nicola Gillan
- South London and Maudsley NHS (National Health Service) Foundation Trust, Maudsley Hospital, London, England
| | - Victoria Hallett
- Department of Psychology, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Stephanie Lietz
- Research Department of Clinical, Educational and Health Psychology, University College London, London, England
| | - Tracy Garnett
- South London and Maudsley NHS (National Health Service) Foundation Trust, Maudsley Hospital, London, England
| | - Angelica Ronald
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England9Department of Psychological Sciences, University of London, London, England
| | - Robert Plomin
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Frühling Rijsdijk
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Francesca Happé
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England
| | - Patrick Bolton
- MRC Social, Genetic, and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, England2Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology, and Neuroscience, K
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Desachy G, Croen LA, Torres AR, Kharrazi M, Delorenze GN, Windham GC, Yoshida CK, Weiss LA. Increased female autosomal burden of rare copy number variants in human populations and in autism families. Mol Psychiatry 2015; 20:170-5. [PMID: 25582617 DOI: 10.1038/mp.2014.179] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/28/2014] [Accepted: 11/13/2014] [Indexed: 01/24/2023]
Abstract
Autosomal genetic variation is presumed equivalent in males and females and makes a major contribution to disease risk. We set out to identify whether maternal copy number variants (CNVs) contribute to autism spectrum disorders (ASDs). Surprisingly, we observed a higher autosomal burden of large, rare CNVs in females in the population, reflected in, but not unique to, ASD families. Meta-analysis across control data sets confirms female excess in CNV number (P=2.1 × 10(-5)) and gene content (P=4.1 × 10(-3)). We additionally observed CNV enrichment in ASD mothers compared with control mothers (P=0.03). We speculate that tolerance for CNV burden contributes to decreased female fetal loss in the population and that ASD-specific maternal CNV burden may contribute to high sibling recurrence. These data emphasize the need for study of familial CNV risk factors in ASDs and the requirement of sex-matched comparisons.
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Affiliation(s)
- G Desachy
- Department of Psychiatry and Institute for Human Genetics, UCSF, San Francisco, CA, USA
| | - L A Croen
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA
| | - A R Torres
- Center for Persons with Disabilities, Utah State University, Logan, UT, USA
| | - M Kharrazi
- Genetic Disease Screening Program, California Department of Public Health, Richmond, CA, USA
| | - G N Delorenze
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA
| | - G C Windham
- Division of Environmental and Occupational Disease Control, California Department of Public Health, Richmond, CA, USA
| | - C K Yoshida
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA
| | - L A Weiss
- Department of Psychiatry and Institute for Human Genetics, UCSF, San Francisco, CA, USA
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Kim YS, Leventhal BL. Genetic epidemiology and insights into interactive genetic and environmental effects in autism spectrum disorders. Biol Psychiatry 2015; 77:66-74. [PMID: 25483344 PMCID: PMC4260177 DOI: 10.1016/j.biopsych.2014.11.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 10/31/2014] [Accepted: 11/02/2014] [Indexed: 12/27/2022]
Abstract
Understanding the pathogenesis of neurodevelopmental disorders has proven to be challenging. Using autism spectrum disorder (ASD) as a paradigmatic neurodevelopmental disorder, this article reviews the existing literature on the etiological substrates of ASD and explores how genetic epidemiology approaches including gene-environment interactions (G×E) can play a role in identifying factors associated with ASD etiology. New genetic and bioinformatics strategies have yielded important clues to ASD genetic substrates. The next steps for understanding ASD pathogenesis require significant effort to focus on how genes and environment interact with one another in typical development and its perturbations. Along with larger sample sizes, future study designs should include sample ascertainment that is epidemiologic and population-based to capture the entire ASD spectrum with both categorical and dimensional phenotypic characterization; environmental measurements with accuracy, validity, and biomarkers; statistical methods to address population stratification, multiple comparisons, and G×E of rare variants; animal models to test hypotheses; and new methods to broaden the capacity to search for G×E, including genome-wide and environment-wide association studies, precise estimation of heritability using dense genetic markers, and consideration of G×E both as the disease cause and a disease course modifier. Although examination of G×E appears to be a daunting task, tremendous recent progress in gene discovery has opened new horizons for advancing our understanding of the role of G×E in the pathogenesis of ASD and ultimately identifying the causes, treatments, and even preventive measures for ASD and other neurodevelopmental disorders.
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Affiliation(s)
- Young Shin Kim
- Department of Psychiatry, University of California, San Francisco, San Francisco, California..
| | - Bennett L Leventhal
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, South Korea
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Abstract
The present study examined genetic and shared environment contributions to quantitatively-measured autism symptoms and categorically-defined autism spectrum disorders (ASD). Participants included 568 twins from the Interactive Autism Network. Autism symptoms were obtained using the Social Communication Questionnaire and Social Responsiveness Scale. Categorically-defined ASD was based on clinical diagnoses. DeFries-Fulker and liability threshold models examined etiologic influences. Very high heritability was observed for extreme autism symptom levels ([Formula: see text]). Extreme levels of social and repetitive behavior symptoms were strongly influenced by common genetic factors. Heritability of categorically-defined ASD diagnosis was comparatively low (.21, 95 % CI 0.15-0.28). High heritability of extreme autism symptom levels confirms previous observations of strong genetic influences on autism. Future studies will require large, carefully ascertained family pedigrees and quantitative symptom measurements.
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Petrinovic MM, Künnecke B. Neuroimaging endophenotypes in animal models of autism spectrum disorders: lost or found in translation? Psychopharmacology (Berl) 2014; 231:1167-89. [PMID: 23852013 DOI: 10.1007/s00213-013-3200-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 06/26/2013] [Indexed: 11/26/2022]
Abstract
RATIONALE Autism spectrum disorder(s) (ASDs) is a neurodevelopmental disorder characterized by stereotyped behaviours and impairments in communication and social interactions. This heterogeneity has been a major obstacle in uncovering the aetiology and biomarkers of ASDs. Rodent models with genetic modifications or environmental insults have been created to study particular endophenotypes and bridge the gap between genetics and behavioural phenotypes. Translational neuroimaging modalities with their ability to screen the brain noninvasively and yield structural, biochemical and functional information provide a unique platform for discovery and evaluation of such endophenotypes in preclinical and clinical research. OBJECTIVES We reviewed literature on translational neuroimaging in rodent models of ASDs. The most prominent models will be described and the respective neuroimaging endophenotypes will be discussed with reference to human data. A perspective on future directions of translational neuroimaging in animal models of ASDs will be given. RESULTS AND CONCLUSIONS To date, we experience a proliferation of rodent models which recapitulate specific liabilities identified in ASDs patients. Translational neuroimaging in these models is emerging but is skewed towards magnetic resonance imaging (MRI) modalities. Volumetric and structural assessments of the brain are dominating and a host of endophenotypes have been reported that allude to findings in ASDs patients but with only few to converge among the models. Caveats of current studies are the diverging biological conditions related to genetic background and age of the animals. It is anticipated that longitudinal and functional assessments will gain much importance and will help elucidating mechanistic relationship between behavioural and structural endophenotypes.
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Affiliation(s)
- Marija M Petrinovic
- F. Hoffmann-La Roche AG, pRED, Pharma Research and Early Development, DTA Neuroscience, Building 68, Room 327A, Grenzacherstrasse 124, 4070, Basel, Switzerland
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Field SS. Interaction of genes and nutritional factors in the etiology of autism and attention deficit/hyperactivity disorders: a case control study. Med Hypotheses 2014; 82:654-61. [PMID: 24685108 DOI: 10.1016/j.mehy.2014.02.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 02/12/2014] [Accepted: 02/17/2014] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To compare risk factors of attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) to age/sex-matched controls with particular attention to family history, parental age and nutrition. METHOD 31 ASD and 81 ADHD patients were compared to 612 age/sex-matched controls by reviewing charts for parental age, sibling order, gestational age, and early feeding, and by parental interview for early feeding and family history of psychopathology on affected patients and 139 of those controls. FINDINGS Parental age affected ASD and ADHD females but not males. First-born males were at increased risk for both disorders even though their siblings had older parents and their parents were not more likely to stop having children. Breastfeeding in the absence of parental psychopathology reduced ADHD risk, but breastfeeding of first-born males by older mothers with psychopathology was a risk for ASD. Breastfeeding was only a risk for ADHD if the mother had psychopathology. Parent emigration from a place of high fish consumption was a significant ASD risk factor. RESULTING HYPOTHESES ADHD and ASD share risk factors due to shared genetic and nutritional interactions, likely revolving around deficiencies of omega-3 fatty acids (n3FAs) during brain development. Fatty acid metabolism genes are important in that process. The 4:1 male to female ratio for both disorders results from hormonally driven fat metabolism differences. Risk factors for both disorders including maternal smoking, prematurity, and gestational diabetes may also be attributed to their effect on n3FA supplies. Breastfeeding can be a risk factor when the mother's genes and/or age affect her milk quality. Parental age and gene defects may affect female more than male offspring. Childbirth with adequate spacing and breastfeeding can override maternal age and protect subsequent offspring. Genetic variations in fat metabolism can be influenced by cultural/geographic diet, causing deficiencies in offspring with migration-influenced diet changes. Interaction of n3FA deficient diets, delayed child-bearing, and breastfeeding by mothers with psychopathology may be important factors in the rising incidence of ASD and ADHD in recent decades. Partial prevention through diet and supplements may be possible.
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Affiliation(s)
- Scott S Field
- Huntsville Hospital, University of Alabama in Birmingham (Huntsville Campus), United States.
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Rossman IT, Lin L, Morgan KM, Digiovine M, Van Buskirk EK, Kamdar S, Millonig JH, Dicicco-Bloom E. Engrailed2 modulates cerebellar granule neuron precursor proliferation, differentiation and insulin-like growth factor 1 signaling during postnatal development. Mol Autism 2014; 5:9. [PMID: 24507165 PMCID: PMC3932947 DOI: 10.1186/2040-2392-5-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 01/14/2014] [Indexed: 01/16/2023] Open
Abstract
Background The homeobox transcription factor Engrailed2 (En2) has been studied extensively in neurodevelopment, particularly in the midbrain/hindbrain region and cerebellum, where it exhibits dynamic patterns of expression and regulates cell patterning and morphogenesis. Because of its roles in regulating cerebellar development and evidence of cerebellar pathology in autism spectrum disorder (ASD), we previously examined an ENGRAILED2 association and found evidence to support EN2 as a susceptibility gene, a finding replicated by several other investigators. However, its functions at the cell biological level remain undefined. In the mouse, En2 gene is expressed in granule neuron precursors (GNPs) just as they exit the cell cycle and begin to differentiate, raising the possibility that En2 may modulate these developmental processes. Methods To define En2 functions, we examined proliferation, differentiation and signaling pathway activation in En2 knockout (KO) and wild-type (WT) GNPs in response to a variety of extracellular growth factors and following En2 cDNA overexpression in cell culture. In vivo analyses of cerebellar GNP proliferation as well as responses to insulin-like growth factor-1 (IGF1) treatment were also conducted. Results Proliferation markers were increased in KO GNPs in vivo and in 24-h cultures, suggesting En2 normally serves to promote cell cycle exit. Significantly, IGF1 stimulated greater DNA synthesis in KO than WT cells in culture, a finding associated with markedly increased phospho-S6 kinase activation. Similarly, there was three-fold greater DNA synthesis in the KO cerebellum in response to IGF1 in vivo. On the other hand, KO GNPs exhibited reduced neurite outgrowth and differentiation. Conversely, En2 overexpression increased cell cycle exit and promoted neuronal differentiation. Conclusions In aggregate, our observations suggest that the ASD-associated gene En2 promotes GNP cell cycle exit and differentiation, and modulates IGF1 activity during postnatal cerebellar development. Thus, genetic/epigenetic alterations of EN2 expression may impact proliferation, differentiation and IGF1 signaling as possible mechanisms that may contribute to ASD pathogenesis.
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Affiliation(s)
| | | | | | | | | | | | | | - Emanuel Dicicco-Bloom
- Department of Neuroscience & Cell Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 675 Hoes, Lane, Piscataway, NJ 08854, USA.
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Abstract
Autism is a behaviorally defined developmental disorder of the brain almost always presenting in infancy or the preschool years. Its symptoms persist life-long, although partial compensation is possible through targeted special education that addresses children's deficits in sociability, verbal and non-verbal communication, and atypical range of interests, activities, and cognitive skills. Although a majority of autistic individuals are mentally deficient, IQ is not a defining feature and verbal autistic persons of normal intelligence are increasingly being identified, referred to as Asperger syndrome. Meager neuropathologic data have disclosed subtle prenatal cellular limbic and cerebellar abnormalities. Autism is associated with a variety of defined genetic and acquired conditions, with multifactorial genetic traits, alone or interacting with environmental events, presumably responsible for most unexplained cases. Autistic regression is frequent and poorly understood and may be associated with clinical or subclinical epilepsy. Unravelling the neurobiologic basis of a disorder that may affect 1-2 in 1000 children will require a concerted multidisciplinary attack.
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Affiliation(s)
- I Rapin
- Saul R. Korey Department of Neurology, Department of Pediatrics, and Rose F. Kennedy Center for Research in Mental Retardation and Human Development, Albert Einstein College of Medicine, Bronx, NY, USA
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Tsang KM, Croen LA, Torres AR, Kharrazi M, Delorenze GN, Windham GC, Yoshida CK, Zerbo O, Weiss LA. A genome-wide survey of transgenerational genetic effects in autism. PLoS One 2013; 8:e76978. [PMID: 24204716 PMCID: PMC3811986 DOI: 10.1371/journal.pone.0076978] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 08/28/2013] [Indexed: 12/15/2022] Open
Abstract
Effects of parental genotype or parent-offspring genetic interaction are well established in model organisms for a variety of traits. However, these transgenerational genetic models are rarely studied in humans. We have utilized an autism case-control study with 735 mother-child pairs to perform genome-wide screening for maternal genetic effects and maternal-offspring genetic interaction. We used simple models of single locus parent-child interaction and identified suggestive results (P<10−4) that cannot be explained by main effects, but no genome-wide significant signals. Some of these maternal and maternal-child associations were in or adjacent to autism candidate genes including: PCDH9, FOXP1, GABRB3, NRXN1, RELN, MACROD2, FHIT, RORA, CNTN4, CNTNAP2, FAM135B, LAMA1, NFIA, NLGN4X, RAPGEF4, and SDK1. We attempted validation of potential autism association under maternal-specific models using maternal-paternal comparison in family-based GWAS datasets. Our results suggest that further study of parental genetic effects and parent-child interaction in autism is warranted.
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Affiliation(s)
- Kathryn M. Tsang
- Department of Psychiatry and Institute for Human Genetics, University of California San Francisco, San Francisco, California, United States of America
| | - Lisa A. Croen
- Division of Research, Kaiser Permanente Northern California, Oakland, California, United States of America
| | - Anthony R. Torres
- Center for Persons with Disabilities, Utah State University, Logan, Utah, United States of America
| | - Martin Kharrazi
- Genetic Disease Screening Program, California Department of Health Services, Richmond, California, United States of America
| | - Gerald N. Delorenze
- Division of Research, Kaiser Permanente Northern California, Oakland, California, United States of America
| | - Gayle C. Windham
- Division of Environmental and Occupational Disease Control, California Department of Health Services, Richmond, California, United States of America
| | - Cathleen K. Yoshida
- Division of Research, Kaiser Permanente Northern California, Oakland, California, United States of America
| | - Ousseny Zerbo
- Division of Research, Kaiser Permanente Northern California, Oakland, California, United States of America
| | - Lauren A. Weiss
- Department of Psychiatry and Institute for Human Genetics, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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Neuropathology and animal models of autism: genetic and environmental factors. AUTISM RESEARCH AND TREATMENT 2013; 2013:731935. [PMID: 24151553 PMCID: PMC3787615 DOI: 10.1155/2013/731935] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 08/07/2013] [Accepted: 08/09/2013] [Indexed: 02/05/2023]
Abstract
Autism is a heterogeneous behaviorally defined neurodevelopmental disorder. It is defined by the presence of marked social deficits, specific language abnormalities, and stereotyped repetitive patterns of behavior. Because of the variability in the behavioral phenotype of the disorder among patients, the term autism spectrum disorder has been established. In the first part of this review, we provide an overview of neuropathological findings from studies of autism postmortem brains and identify the cerebellum as one of the key brain regions that can play a role in the autism phenotype. We review research findings that indicate possible links between the environment and autism including the role of mercury and immune-related factors. Because both genes and environment can alter the structure of the developing brain in different ways, it is not surprising that there is heterogeneity in the behavioral and neuropathological phenotypes of autism spectrum disorders. Finally, we describe animal models of autism that occur following insertion of different autism-related genes and exposure to environmental factors, highlighting those models which exhibit both autism-like behavior and neuropathology.
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Joseph J. The lost study: a 1998 adoption study of personality that found no genetic relationship between birthparents and their 240 adopted-away biological offspring. ADVANCES IN CHILD DEVELOPMENT AND BEHAVIOR 2013; 45:93-124. [PMID: 23865114 DOI: 10.1016/b978-0-12-397946-9.00005-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In 1998, Robert Plomin and his Colorado Adoption Project (CAP) colleagues published the results of a longitudinal adoption study of personality. They found an average personality test score correlation of only 0.01 between birthparents and their 240 adopted-away 16-year-old biological offspring, suggesting no genetic influences on personality. However, the researchers interpreted their results in the context of previous twin studies, produced an average 14% heritability estimate, and concluded that nonadditive genetic factors underlie personality traits. The author challenges these conclusions and notes that the near-zero correlation stands in contrast to other types of behavioral genetic methods, such as twin studies, that are more vulnerable to environmental confounds and other biases. The author shows that authoritative psychology texts frequently fail to mention this 1998 CAP study. When it is mentioned, the original researchers' conclusions are usually accepted without critical analysis. The author also assesses the results in the context of the 20-year failure to discover the genes that behavioral geneticists believe underlie personality traits. He concludes that this 1998 investigation is a "lost study" in the sense that, although it is one of the most methodologically sound behavioral genetic studies ever performed, its results are largely unknown.
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