1
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Vision-assisted recognition of stereotype behaviors for early diagnosis of Autism Spectrum Disorders. Neurocomputing 2021. [DOI: 10.1016/j.neucom.2021.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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2
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Wang J, Poliquin S, Mermer F, Eissman J, Delpire E, Wang J, Shen W, Cai K, Li BM, Li ZY, Xu D, Nwosu G, Flamm C, Liao WP, Shi YW, Kang JQ. Endoplasmic reticulum retention and degradation of a mutation in SLC6A1 associated with epilepsy and autism. Mol Brain 2020; 13:76. [PMID: 32398021 PMCID: PMC7218610 DOI: 10.1186/s13041-020-00612-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 04/28/2020] [Indexed: 01/12/2023] Open
Abstract
Mutations in SLC6A1, encoding γ-aminobutyric acid (GABA) transporter 1 (GAT-1), have been recently associated with a spectrum of epilepsy syndromes, intellectual disability and autism in clinic. However, the pathophysiology of the gene mutations is far from clear. Here we report a novel SLC6A1 missense mutation in a patient with epilepsy and autism spectrum disorder and characterized the molecular defects of the mutant GAT-1, from transporter protein trafficking to GABA uptake function in heterologous cells and neurons. The heterozygous missense mutation (c1081C to A (P361T)) in SLC6A1 was identified by exome sequencing. We have thoroughly characterized the molecular pathophysiology underlying the clinical phenotypes. We performed EEG recordings and autism diagnostic interview. The patient had neurodevelopmental delay, absence epilepsy, generalized epilepsy, and 2.5–3 Hz generalized spike and slow waves on EEG recordings. The impact of the mutation on GAT-1 function and trafficking was evaluated by 3H GABA uptake, structural simulation with machine learning tools, live cell confocal microscopy and protein expression in mouse neurons and nonneuronal cells. We demonstrated that the GAT-1(P361T) mutation destabilizes the global protein conformation and reduces total protein expression. The mutant transporter protein was localized intracellularly inside the endoplasmic reticulum (ER) with a pattern of expression very similar to the cells treated with tunicamycin, an ER stress inducer. Radioactive 3H-labeled GABA uptake assay indicated the mutation reduced the function of the mutant GAT-1(P361T), to a level that is similar to the cells treated with GAT-1 inhibitors. In summary, this mutation destabilizes the mutant transporter protein, which results in retention of the mutant protein inside cells and reduction of total transporter expression, likely via excessive endoplasmic reticulum associated degradation. This thus likely causes reduced functional transporter number on the cell surface, which then could cause the observed reduced GABA uptake function. Consequently, malfunctioning GABA signaling may cause altered neurodevelopment and neurotransmission, such as enhanced tonic inhibition and altered cell proliferation in vivo. The pathophysiology due to severely impaired GAT-1 function may give rise to a wide spectrum of neurodevelopmental phenotypes including autism and epilepsy.
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Affiliation(s)
- Jie Wang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Sarah Poliquin
- The Neuroscience Program, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Felicia Mermer
- The Neuroscience Program, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Jaclyn Eissman
- The Neuroscience Program, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University Department of Anesthesiology, Vanderbilt University, Nashville, TN, 37232, USA
| | - Juexin Wang
- Department of Electrical Engineering & Computer Science and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Wangzhen Shen
- Department of Neurology, Vanderbilt University Medical Center, Nashville, USA
| | - Kefu Cai
- Department of Neurology, Vanderbilt University Medical Center, Nashville, USA.,Department of Neurology, Affiliated Hospital, Nantong University, Nantong, 226001, Jiangsu, China
| | - Bing-Mei Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Zong-Yan Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Dong Xu
- Department of Electrical Engineering & Computer Science and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Gerald Nwosu
- Department of Neurology, Vanderbilt University Medical Center, Nashville, USA.,Neuroscience Graduate Program, Vanderbilt-Meharry Alliance, Vanderbilt University, Nashville, TN, 37235, USA
| | - Carson Flamm
- The Neuroscience Program, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Wei-Ping Liao
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Yi-Wu Shi
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University; Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Jing-Qiong Kang
- Department of Neurology, Vanderbilt University Medical Center, Nashville, USA. .,Department of Pharmacology, Vanderbilt University, Vanderbilt Kennedy Center of Human Development, Vanderbilt Brain Institute, 6147 MRBIII, 465 21st Ave. South, Nashville, TN, 37232, USA.
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3
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Behavioral and neuroanatomical approaches in models of neurodevelopmental disorders: opportunities for translation. Curr Opin Neurol 2019; 31:126-133. [PMID: 29493556 DOI: 10.1097/wco.0000000000000537] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW This review highlights the invaluable contribution of in-vivo rodent models in dissecting the underlying neurobiology for numerous neurodevelopmental disorders. Currently, models are routinely generated with precision genomics and characterized for research on neurodevelopmental disorders. In order to impact translation, outcome measures that are translationally relevant are essential. This review emphasizes the importance of accurate neurobehavioral and anatomical analyses. RECENT FINDINGS Numerous well validated assays for testing alterations across behavioral domains with sensitivity and throughput have become important tools for studying the effects of genetic mutations on neurodevelopment. Recent work has highlighted relationships and links between behavioral outcomes and various anatomical metrics from neuroimaging via magnetic resonance. These readouts are biological markers and outcome measures for translational research and will be have important roles for genetic or pharmacologic intervention strategies. SUMMARY Combinatorial approaches that leverage translationally relevant behavior and neuroanatomy can be used to develop a platform for assessment of cutting edge preclinical models. Reliable, robust behavioral phenotypes in preclinical model systems, with clustering of brain disease will lead to well informed, precise biochemical mechanistic hypotheses. Ultimately, these steadfast workhorse techniques will accelerate the progress of developing and testing targeted treatments for multiple neurodevelopmental disorders.
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Kim YY, Roubal I, Lee YS, Kim JS, Hoang M, Mathiyakom N, Kim Y. Alcohol-Induced Molecular Dysregulation in Human Embryonic Stem Cell-Derived Neural Precursor Cells. PLoS One 2016; 11:e0163812. [PMID: 27682028 PMCID: PMC5040434 DOI: 10.1371/journal.pone.0163812] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/14/2016] [Indexed: 01/08/2023] Open
Abstract
Adverse effect of alcohol on neural function has been well documented. Especially, the teratogenic effect of alcohol on neurodevelopment during embryogenesis has been demonstrated in various models, which could be a pathologic basis for fetal alcohol spectrum disorders (FASDs). While the developmental defects from alcohol abuse during gestation have been described, the specific mechanisms by which alcohol mediates these injuries have yet to be determined. Recent studies have shown that alcohol has significant effect on molecular and cellular regulatory mechanisms in embryonic stem cell (ESC) differentiation including genes involved in neural development. To test our hypothesis that alcohol induces molecular alterations during neural differentiation we have derived neural precursor cells from pluripotent human ESCs in the presence or absence of ethanol treatment. Genome-wide transcriptomic profiling identified molecular alterations induced by ethanol exposure during neural differentiation of hESCs into neural rosettes and neural precursor cell populations. The Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis on significantly altered genes showed potential ethanol’s effect on JAK-STAT signaling pathway, neuroactive ligand-receptor interaction, Toll-like receptor (TLR) signaling pathway, cytokine-cytokine receptor interaction and regulation of autophagy. We have further quantitatively verified ethanol-induced alterations of selected candidate genes. Among verified genes we further examined the expression of P2RX3, which is associated with nociception, a peripheral pain response. We found ethanol significantly reduced the level of P2RX3 in undifferentiated hESCs, but induced the level of P2RX3 mRNA and protein in hESC-derived NPCs. Our result suggests ethanol-induced dysregulation of P2RX3 along with alterations in molecules involved in neural activity such as neuroactive ligand-receptor interaction may be a molecular event associated with alcohol-related peripheral neuropathy of an enhanced nociceptive response.
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Affiliation(s)
- Yi Young Kim
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Ivan Roubal
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Youn Soo Lee
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Jin Seok Kim
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Michael Hoang
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Nathan Mathiyakom
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
| | - Yong Kim
- Laboratory of Stem Cell & Cancer Epigenetic Research, School of Dentistry, University of California Los Angeles, 10833 Le Conte Avenue, 73–041 CHS, Los Angeles, CA, 90095, United States of America
- Center for Oral and Head/Neck Oncology Research Center, Division of Oral Biology & Medicine, UCLA School of Dentistry, 10833 Le Conte Avenue, 73–022 CHS, Los Angeles, CA, 90095, United States of America
- UCLA’s Jonsson Comprehensive Cancer Center, 8–684 Factor Building, Box 951781, Los Angeles, CA, 90095, United States of America
- UCLA Broad Stem Cell Research Center, Box 957357, Los Angeles, CA, 90095, United States of America
- * E-mail:
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5
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Homs A, Codina-Solà M, Rodríguez-Santiago B, Villanueva CM, Monk D, Cuscó I, Pérez-Jurado LA. Genetic and epigenetic methylation defects and implication of the ERMN gene in autism spectrum disorders. Transl Psychiatry 2016; 6:e855. [PMID: 27404287 PMCID: PMC5545709 DOI: 10.1038/tp.2016.120] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 04/01/2016] [Accepted: 05/08/2016] [Indexed: 12/11/2022] Open
Abstract
Autism spectrum disorders (ASD) are highly heritable and genetically complex conditions. Although highly penetrant mutations in multiple genes have been identified, they account for the etiology of <1/3 of cases. There is also strong evidence for environmental contribution to ASD, which can be mediated by still poorly explored epigenetic modifications. We searched for methylation changes on blood DNA of 53 male ASD patients and 757 healthy controls using a methylomic array (450K Illumina), correlated the variants with transcriptional alterations in blood RNAseq data, and performed a case-control association study of the relevant findings in a larger cohort (394 cases and 500 controls). We found 700 differentially methylated CpGs, most of them hypomethylated in the ASD group (83.9%), with cis-acting expression changes at 7.6% of locations. Relevant findings included: (1) hypomethylation caused by rare genetic variants (meSNVs) at six loci (ERMN, USP24, METTL21C, PDE10A, STX16 and DBT) significantly associated with ASD (q-value <0.05); and (2) clustered epimutations associated to transcriptional changes in single-ASD patients (n=4). All meSNVs and clustered epimutations were inherited from unaffected parents. Resequencing of the top candidate genes also revealed a significant load of deleterious mutations affecting ERMN in ASD compared with controls. Our data indicate that inherited methylation alterations detectable in blood DNA, due to either genetic or epigenetic defects, can affect gene expression and contribute to ASD susceptibility most likely in an additive manner, and implicate ERMN as a novel ASD gene.
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Affiliation(s)
- A Homs
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain,Institut Hospital del Mar d’Investigacions Mèdiques, Barcelona, Spain,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain
| | - M Codina-Solà
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain,Institut Hospital del Mar d’Investigacions Mèdiques, Barcelona, Spain,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain
| | | | - C M Villanueva
- Center for Research in Environmental Epidemiology, Barcelona, Spain,Consorcio de Investigación Biomédica de Epidemiología y Salud Pública, Barcelona, Spain
| | - D Monk
- Cancer Epigenetics Group, Institut d'Investigació Biomedica de Bellvitge, Hospital Duran i Reynals, Barcelona, Spain
| | - I Cuscó
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain,Institut Hospital del Mar d’Investigacions Mèdiques, Barcelona, Spain,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain,Genetics Unit, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Dr. Aiguader 88, Barcelona 08003, Spain. E-mails: and
| | - L A Pérez-Jurado
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain,Institut Hospital del Mar d’Investigacions Mèdiques, Barcelona, Spain,Centro de Investigación Biomédica en Red de Enfermedades Raras, Barcelona, Spain,Genetics Unit, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Dr. Aiguader 88, Barcelona 08003, Spain. E-mails: and
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Sener EF, Cıkılı Uytun M, Korkmaz Bayramov K, Zararsiz G, Oztop DB, Canatan H, Ozkul Y. The roles of CC2D1A and HTR1A gene expressions in autism spectrum disorders. Metab Brain Dis 2016; 31:613-9. [PMID: 26782176 DOI: 10.1007/s11011-016-9795-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 01/12/2016] [Indexed: 10/22/2022]
Abstract
Classical autism belongs to a group of heterogeneous disorders known as autism spectrum disorders (ASD). Autism is defined as a neurodevelopmental disorder, characterized by repetitive stereotypic behaviors or restricted interests, social withdrawal, and communication deficits. Numerous susceptibility genes and chromosomal abnormalities have been reported in association with autism but the etiology of this disorder is unknown in many cases. CC2D1A gene has been linked to mental retardation (MR) in a family with a large deletion before. Intellectual disability (ID) is a common feature of autistic cases. Therefore we aimed to investigate the expressions of CC2D1A and HTR1A genes with the diagnosis of autism in Turkey. Forty-four autistic patients (35 boys, 9 girls) and 27 controls were enrolled and obtained whole blood samples to isolate RNA samples from each participant. CC2D1A and HTR1A gene expressions were assessed by quantitative Real-Time PCR (qRT-PCR) in Genome and Stem Cell Center, Erciyes University. Both expressions of CC2D1A and HTR1A genes studied on ASD cases and controls were significantly different (p < 0.001). The expression of HTR1A was undetectable in the ASD samples. Comparison of ID and CC2D1A gene expression was also found statistically significant (p = 0.028). CC2D1A gene expression may be used as a candidate gene for ASD cases with ID. Further studies are needed to investigate the potential roles of these CC2D1A and HTR1A genes in their related pathways in ASD.
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Affiliation(s)
- Elif Funda Sener
- Department of Medical Biology, Erciyes University Medical School, 38039, Kayseri, Turkey.
- Genome and Stem Cell Center (GENKOK), Erciyes University, Kayseri, Turkey.
| | - Merve Cıkılı Uytun
- Department of Child Psychiatry, Education and Research Hospital, Kayseri, Turkey
| | - Keziban Korkmaz Bayramov
- Genome and Stem Cell Center (GENKOK), Erciyes University, Kayseri, Turkey
- Department of Medical Genetics, Erciyes University Medical School, 38039, Kayseri, Turkey
| | - Gokmen Zararsiz
- Department of Biostatistics, Erciyes University Medical School, 38039, Kayseri, Turkey
| | - Didem Behice Oztop
- Department of Child Psychiatry, Surp Pirgic Armenian Hospital, Istanbul, Turkey
| | - Halit Canatan
- Department of Medical Biology, Erciyes University Medical School, 38039, Kayseri, Turkey
| | - Yusuf Ozkul
- Genome and Stem Cell Center (GENKOK), Erciyes University, Kayseri, Turkey
- Department of Medical Genetics, Erciyes University Medical School, 38039, Kayseri, Turkey
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7
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Folic acid supplementation: what is new? Fetal, obstetric, long-term benefits and risks. Future Sci OA 2016; 2:FSO116. [PMID: 28031963 PMCID: PMC5137972 DOI: 10.4155/fsoa-2015-0015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/24/2016] [Indexed: 01/08/2023] Open
Abstract
The association between folic acid supplementation, prior to conception and/or during pregnancy and pregnancy outcomes, has been the subject of numerous studies. The worldwide recommendation of folic acid is at least 0.4 mg daily for all women of reproductive age, and 4–5 mg in high-risk women. In addition, evidence shows that folic acid supplementation could modulate other adverse pregnancy outcomes, specifically, in pregnancies complicated by seizure disorders, preeclampsia, anemia, fetal growth restriction and autism. This review summarizes the available national and international guidelines, concerning the indications and dosage of folic acid supplementation during pregnancy. In addition, it describes the potential preventive benefits of folic acid supplementation on multiple maternal and fetal outcomes, as well as potential risks.
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Kardas F, Bayram AK, Demirci E, Akin L, Ozmen S, Kendirci M, Canpolat M, Oztop DB, Narin F, Gumus H, Kumandas S, Per H. Increased Serum Phthalates (MEHP, DEHP) and Bisphenol A Concentrations in Children With Autism Spectrum Disorder: The Role of Endocrine Disruptors in Autism Etiopathogenesis. J Child Neurol 2016; 31:629-35. [PMID: 26450281 DOI: 10.1177/0883073815609150] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 08/18/2015] [Indexed: 12/11/2022]
Abstract
The aim of this study was to investigate the relationship between autism spectrum disorders development and exposure to mono-(2-ethylhexyl)-phthalate (MEHP), di-(2-ethylhexyl)-phthalate (DEHP), and bisphenol A (BPA), 1 of the endocrine disruptors, among phthalates. The study included 48 children with autism spectrum disorder (27 boys, 21 girls) and 41 healthy subjects (24 boys, 17 girls) as controls. Serum MEHP, DEHP, and BPA levels were measured by using high-performance liquid chromatography. Children with autism spectrum disorder had significantly increased serum MEHP, DEHP, and BPA concentrations (0.47 ± 0.14 µg/ml, 2.70 ± 0.90 µg/ml, 1.25 ± 0.30 ng/ml) compared to healthy control subjects (0.29 ± 0.05 µg/ml, 1.62 ± 0.56 µg/ml, 0.88 ± 0.18 ng/ml) respectively (P = .000). The fact that higher serum MEHP, DEHP, and BPA were found levels in the autism spectrum disorder group compared to healthy controls suggests that endocrine disruptors may have a role in the pathogenesis of autism spectrum disorders.
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Affiliation(s)
- Fatih Kardas
- Department of Pediatrics, Division of Pediatric Nutrition and Metabolism, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Ayse Kacar Bayram
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Esra Demirci
- Department of Child Psychiatry, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Leyla Akin
- Department of Pediatrics, Division of Pediatric Endocrinology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Sevgi Ozmen
- Department of Child Psychiatry, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Mustafa Kendirci
- Department of Pediatrics, Division of Pediatric Nutrition and Metabolism, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Mehmet Canpolat
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Didem Behice Oztop
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Figen Narin
- Department of Biochemistry, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Hakan Gumus
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Sefer Kumandas
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
| | - Huseyin Per
- Department of Pediatrics, Division of Pediatric Neurology, School of Medicine, Erciyes University, Kayseri, Turkey
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Keil KP, Lein PJ. DNA methylation: a mechanism linking environmental chemical exposures to risk of autism spectrum disorders? ENVIRONMENTAL EPIGENETICS 2016; 2:dvv012. [PMID: 27158529 PMCID: PMC4856164 DOI: 10.1093/eep/dvv012] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
There is now compelling evidence that gene by environment interactions are important in the etiology of autism spectrum disorders (ASDs). However, the mechanisms by which environmental factors interact with genetic susceptibilities to confer individual risk for ASD remain a significant knowledge gap in the field. The epigenome, and in particular DNA methylation, is a critical gene expression regulatory mechanism in normal and pathogenic brain development. DNA methylation can be influenced by environmental factors such as diet, hormones, stress, drugs, or exposure to environmental chemicals, suggesting that environmental factors may contribute to adverse neurodevelopmental outcomes of relevance to ASD via effects on DNA methylation in the developing brain. In this review, we describe epidemiological and experimental evidence implicating altered DNA methylation as a potential mechanism by which environmental chemicals confer risk for ASD, using polychlorinated biphenyls (PCBs), lead, and bisphenol A (BPA) as examples. Understanding how environmental chemical exposures influence DNA methylation and how these epigenetic changes modulate the risk and/or severity of ASD will not only provide mechanistic insight regarding gene-environment interactions of relevance to ASD but may also suggest potential intervention strategies for these and potentially other neurodevelopmental disorders.
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Affiliation(s)
- Kimberly P. Keil
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Pamela J. Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
- *Correspondence address. Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, 1089 Veterinary Medicine Drive, Davis, CA 95616, USA. Tel:
(530) 752-1970
; Fax:
(530) 752-7690
; E-mail:
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10
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Zhao Y, Castellanos FX. Annual Research Review: Discovery science strategies in studies of the pathophysiology of child and adolescent psychiatric disorders--promises and limitations. J Child Psychol Psychiatry 2016; 57:421-39. [PMID: 26732133 PMCID: PMC4760897 DOI: 10.1111/jcpp.12503] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND Psychiatric science remains descriptive, with a categorical nosology intended to enhance interobserver reliability. Increased awareness of the mismatch between categorical classifications and the complexity of biological systems drives the search for novel frameworks including discovery science in Big Data. In this review, we provide an overview of incipient approaches, primarily focused on classically categorical diagnoses such as schizophrenia (SZ), autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD), but also reference convincing, if focal, advances in cancer biology, to describe the challenges of Big Data and discovery science, and outline approaches being formulated to overcome existing obstacles. FINDINGS A paradigm shift from categorical diagnoses to a domain/structure-based nosology and from linear causal chains to complex causal network models of brain-behavior relationship is ongoing. This (r)evolution involves appreciating the complexity, dimensionality, and heterogeneity of neuropsychiatric data collected from multiple sources ('broad' data) along with data obtained at multiple levels of analysis, ranging from genes to molecules, cells, circuits, and behaviors ('deep' data). Both of these types of Big Data landscapes require the use and development of robust and powerful informatics and statistical approaches. Thus, we describe Big Data analysis pipelines and the promise and potential limitations in using Big Data approaches to study psychiatric disorders. CONCLUSIONS We highlight key resources available for psychopathological studies and call for the application and development of Big Data approaches to dissect the causes and mechanisms of neuropsychiatric disorders and identify corresponding biomarkers for early diagnosis.
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Affiliation(s)
- Yihong Zhao
- Department of Child and Adolescent Psychiatry, NYU Child Study Center at NYU Langone Medical Center, New York, NY 10016, USA
| | - F. Xavier Castellanos
- Department of Child and Adolescent Psychiatry, NYU Child Study Center at NYU Langone Medical Center, New York, NY 10016, USA,Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
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11
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Immune mediators in the brain and peripheral tissues in autism spectrum disorder. Nat Rev Neurosci 2015; 16:469-86. [PMID: 26189694 DOI: 10.1038/nrn3978] [Citation(s) in RCA: 312] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Increasing evidence points to a central role for immune dysregulation in autism spectrum disorder (ASD). Several ASD risk genes encode components of the immune system and many maternal immune system-related risk factors--including autoimmunity, infection and fetal reactive antibodies--are associated with ASD. In addition, there is evidence of ongoing immune dysregulation in individuals with ASD and in animal models of this disorder. Recently, several molecular signalling pathways--including pathways downstream of cytokines, the receptor MET, major histocompatibility complex class I molecules, microglia and complement factors--have been identified that link immune activation to ASD phenotypes. Together, these findings indicate that the immune system is a point of convergence for multiple ASD-related genetic and environmental risk factors.
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12
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Warrier V, Chee V, Smith P, Chakrabarti B, Baron-Cohen S. A comprehensive meta-analysis of common genetic variants in autism spectrum conditions. Mol Autism 2015; 6:49. [PMID: 26322220 PMCID: PMC4552442 DOI: 10.1186/s13229-015-0041-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 08/17/2015] [Indexed: 12/27/2022] Open
Abstract
Background Autism spectrum conditions (ASC) are a group of neurodevelopmental conditions characterized by difficulties in social interaction and communication alongside repetitive and stereotyped behaviours. ASC are heritable, and common genetic variants contribute substantial phenotypic variability. More than 600 genes have been implicated in ASC to date. However, a comprehensive investigation of candidate gene association studies in ASC is lacking. Methods In this study, we systematically reviewed the literature for association studies for 552 genes associated with ASC. We identified 58 common genetic variants in 27 genes that have been investigated in three or more independent cohorts and conducted a meta-analysis for 55 of these variants. We investigated publication bias and sensitivity and performed stratified analyses for a subset of these variants. Results We identified 15 variants nominally significant for the mean effect size, 8 of which had P values below a threshold of significance of 0.01. Of these 15 variants, 11 were re-investigated for effect sizes and significance in the larger Psychiatric Genomics Consortium dataset, and none of them were significant. Effect direction for 8 of the 11 variants were concordant between both the datasets, although the correlation between the effect sizes from the two datasets was poor and non-significant. Conclusions This is the first study to comprehensively examine common variants in candidate genes for ASC through meta-analysis. While for majority of the variants, the total sample size was above 500 cases and 500 controls, the total sample size was not large enough to accurately identify common variants that contribute to the aetiology of ASC. Electronic supplementary material The online version of this article (doi:10.1186/s13229-015-0041-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Varun Warrier
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, 18B Trumpington Road, Cambridge, CB2 8AH UK
| | - Vivienne Chee
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, 18B Trumpington Road, Cambridge, CB2 8AH UK
| | - Paula Smith
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, 18B Trumpington Road, Cambridge, CB2 8AH UK
| | - Bhismadev Chakrabarti
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, 18B Trumpington Road, Cambridge, CB2 8AH UK.,Centre for Integrative Neuroscience and Neurodynamics, School of Psychology and Clinical Language Sciences, University of Reading, Reading, UK
| | - Simon Baron-Cohen
- Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, 18B Trumpington Road, Cambridge, CB2 8AH UK.,CLASS Clinic, Cambridgeshire and Peterborough NHS Foundation Trust (CPFT), Cambridgeshire, UK
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13
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Kiser DP, Rivero O, Lesch KP. Annual research review: The (epi)genetics of neurodevelopmental disorders in the era of whole-genome sequencing--unveiling the dark matter. J Child Psychol Psychiatry 2015; 56:278-95. [PMID: 25677560 DOI: 10.1111/jcpp.12392] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/13/2015] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND SCOPE Neurodevelopmental disorders (NDDs) are defined by a wide variety of behavioural phenotypes, psychopathology and clinically informed categorical classifications. Diagnostic entities include intellectual disability (ID), the autism spectrum (ASD) and attention-deficit/hyperactivity disorder (ADHD). The aetiopathogenesis of these conditions and disorders involves an interaction between both genetic and environmental risk factors on the developmental trajectory. Despite their remarkable genetic heterogeneity and complexity of pathophysiological mechanisms, NDDs display an overlap in their phenotypic features, a considerable degree of comorbidity as well as sharing of genetic and environmental risk factors. This review aims to provide an overview of the genetics and epigenetic of NDDs. FINDINGS Recent evidence suggests a critical role of defined and tightly regulated neurodevelopmental programs running out of control in NDDs, most notably neuronal proliferation and migration, synapse formation and remodelling, as well as neural network configuration resulting in compromised systems connectivity and function. Moreover, the machinery of epigenetic programming, interacting with genetic liability, impacts many of those processes and pathways, thus modifying vulnerability of, and resilience to, NDDs. Consequently, the categorically defined entities of ID, ADHD and ASD are increasingly viewed as disorders on a multidimensional continuum of molecular and cellular deficiencies in neurodevelopment. As such, this range of NDDs displays a broad phenotypic diversity, which may be explained by a combination and interplay of underlying loss- and potential gain-of-function traits. CONCLUSION In this overview, we discuss a backbone continuum concept of NDDs by summarizing pertinent findings in genetics and epigenetics. We also provide an appraisal of the genetic overlap versus differences, with a focus on genome-wide screening approaches for (epi)genetic variation. Finally, we conclude with insights from evolutionary psychobiology suggesting positive selection for discrete NDD-associated traits.
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Affiliation(s)
- Dominik P Kiser
- Division of Molecular Psychiatry, Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Wuerzburg, Wuerzburg, Germany
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14
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Lee JY, Kwak M, Lee PCW. Impairment of social behavior and communication in mice lacking the Uba6-dependent ubiquitin activation system. Behav Brain Res 2014; 281:78-85. [PMID: 25523030 DOI: 10.1016/j.bbr.2014.12.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 12/03/2014] [Accepted: 12/07/2014] [Indexed: 01/31/2023]
Abstract
The Uba6-Use1 ubiquitin enzyme cascade is a poorly understood arm of the ubiquitin-proteasome system required for mouse development. Recently, we reported that Uba6 brain-specific knockout (termed NKO) mice display abnormal social behavior and neuronal development due to a decreased spine density and accumulation of Ube3a and Shank3. To better characterize a potential role for NKO mice in autism spectrum disorders (ASDs), we performed a comprehensive behavioral characterization of the social behavior and communication of NKO mice. Our behavioral results confirmed that NKO mice display social impairments, as indicated by fewer vocalizations and decreased social interaction. We conclude that UBA6 NKO mice represent a novel ASD mouse model of anti-social and less verbal behavioral symptoms.
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Affiliation(s)
- Ji Yeon Lee
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736, Republic of Korea; Division of Rheumatology, Department of Internal Medicine, College of Medicine, The Catholic University, Seoul 137-701, Republic of Korea
| | - Minseok Kwak
- Department of Chemistry, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 608-739, Republic of Korea
| | - Peter C W Lee
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736, Republic of Korea.
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15
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Meguid NA, Kandeel WA, Wakeel KE, El-Nofely AA. Anthropometric assessment of a Middle Eastern group of autistic children. World J Pediatr 2014; 10:318-23. [PMID: 25515805 DOI: 10.1007/s12519-014-0510-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 02/06/2014] [Indexed: 12/31/2022]
Abstract
BACKGROUND Growth abnormalities are uniquely associated with autism spectrum disorders (ASD); however, the extent to which growth abnormalities are present has hardly been investigated. The current study aims to compare the differences in anthropometric parameters in a group of autistic Egyptian children and the healthy normal population. METHODS We recruited 100 children with ASD from the Outpatient Clinic for "Autistic Children" at the Medical Research Hospital of Excellence, National Research Centre in Cairo, Egypt. They were diagnosed by DSM-IV criteria of the American Psychiatric Association, Autism Diagnostic Interview-Revised, and Childhood Autism Rating Scale. Of these children at age of 3-10 years, 71 were males and 29 females. Eight anthropometric parameters were assessed in view of data of the healthy Egyptians of pertinent sex and age. RESULTS Weight and body mass index increased because of a significant increase in subcutaneous fat thickness. This tendency with a probable decrease in muscle mass was more evident in male or in older children, likely resulting from sedentary life style and food selectivity. CONCLUSIONS The Z head circumference score and its variance significantly increased especially in males or older children, suggesting the relative overgrowth of the brain in a substantial percentage of Egyptian children with autism. We concluded that increased fat composition in Egyptian autistic children with decreased muscle mass necessitates tailoring a specially designed food supplementation program to ameliorate the severity of autism symptoms.
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Affiliation(s)
- Nagwa A Meguid
- Department of Research on Children with Special Needs, National Research Centre (NRC), Cairo, Egypt,
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16
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Yoo HJ, Yang SY, Cho IH, Park M, Kim SA. Polymorphisms of BDNF gene and autism spectrum disorders: family based association study with korean trios. Psychiatry Investig 2014; 11:319-24. [PMID: 25110506 PMCID: PMC4124192 DOI: 10.4306/pi.2014.11.3.319] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE Autism spectrum disorders (ASDs) are a group of early childhood-onset neurodevelopmental disorders characterized by deficits in social interaction and language skills, and repetitive behaviors. Brain-derived neurotrophic factor (BDNF) plays a critical role in the differentiation of normal neuronal cells during embryonic and postnatal neuronal development through its neurotrophic effects. METHODS In this study, we performed a family-based association test (FBAT) between single nucleotide polymorphisms (SNPs; rs6265, rs11030101, rs7103411, and rs7103873) or haplotypes in the BDNF gene and affection status or several quantitative traits characterized by ADI-R with151 Korean trios, including a child diagnosed as ASDs. RESULTS While no significant association was found between SNPs or haplotypes and the ASDs disease status, a quantitative transmission disequilibrium test (QTDT) by using quantitative traits identified associations of the SNPs (rs6265 and rs11030101) with a domain score for "Restricted, Repetitive and Stereotyped patterns of behavior" (C domain), especially at the subdomain scores for "encompassing preoccupation or circumscribed pattern of interest" (C1) (rs6265A allele, dominant model, p-value=0.019; rs11030101 A allele, additive model, p-value=0.015) and "preoccupations with part of objects or non-functional elements of material" (C4) (rs11030101 A allele, additive model, p-value=0.015) within the ADI-R diagnostic algorithm. In addition, significant associations were also identified between the haplotypes and these quantitative traits (C1, p-value=0.016; C4, p-value=0.012). CONCLUSION We conclude that BDNF gene polymorphisms have a possible role in the pathogenesis of ASDs.
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Affiliation(s)
- Hee Jeong Yoo
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - So Young Yang
- Department of Pharmacology, Chungnam National University College of Pharmacy, Daejeon, Republic of Korea
| | - In Hee Cho
- Department of Psychiatry, Gachon University of Medicine and Science, Incheon, Republic of Korea
| | - Mira Park
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Soon Ae Kim
- Department of Pharmacology, School of Medicine, Eulji University, Daejeon, Republic of Korea
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Zhubi A, Cook EH, Guidotti A, Grayson DR. Epigenetic Mechanisms in Autism Spectrum Disorder. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 115:203-44. [DOI: 10.1016/b978-0-12-801311-3.00006-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Sampath S, Bhat S, Gupta S, O’Connor A, West AB, Arking DE, Chakravarti A. Defining the contribution of CNTNAP2 to autism susceptibility. PLoS One 2013; 8:e77906. [PMID: 24147096 PMCID: PMC3798378 DOI: 10.1371/journal.pone.0077906] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Accepted: 09/05/2013] [Indexed: 12/31/2022] Open
Abstract
Multiple lines of genetic evidence suggest a role for CNTNAP2 in autism. To assess its population impact we studied 2148 common single nucleotide polymorphisms (SNPs) using transmission disequilibrium test (TDT) across the entire ~3.3 Mb CNTNAP2 locus in 186 (408 trios) multiplex and 323 simplex families with autistic spectrum disorder (ASD). This analysis yielded two SNPs with nominal statistical significance (rs17170073, p = 2.0 x 10-4; rs2215798, p = 1.6 x 10-4) that did not survive multiple testing. In a combined analysis of all families, two highly correlated (r2 = 0.99) SNPs in intron 14 showed significant association with autism (rs2710093, p = 9.0 x 10-6; rs2253031, p = 2.5 x 10-5). To validate these findings and associations at SNPs from previous autism studies (rs7794745, rs2710102 and rs17236239) we genotyped 2051 additional families (572 multiplex and 1479 simplex). None of these variants were significantly associated with ASD after corrections for multiple testing. The analysis of Mendelian errors within each family did not indicate any segregating deletions. Nevertheless, a study of CNTNAP2 gene expression in brains of autistic patients and of normal controls, demonstrated altered expression in a subset of patients (p = 1.9 x10-5). Consequently, this study suggests that although CNTNAP2 dysregulation plays a role in some cases, its population contribution to autism susceptibility is limited.
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Affiliation(s)
- Srirangan Sampath
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
| | - Shambu Bhat
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Simone Gupta
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Ashley O’Connor
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Andrew B. West
- Department of Neurology and Neurobiology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Dan E. Arking
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Aravinda Chakravarti
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetics Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
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19
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de Lacy N, King BH. Revisiting the relationship between autism and schizophrenia: toward an integrated neurobiology. Annu Rev Clin Psychol 2013; 9:555-87. [PMID: 23537488 DOI: 10.1146/annurev-clinpsy-050212-185627] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Schizophrenia and autism have been linked since their earliest descriptions. Both are disorders of cerebral specialization originating in the embryonic period. Genetic, molecular, and cytologic research highlights a variety of shared contributory mechanisms that may lead to patterns of abnormal connectivity arising from altered development and topology. Overt behavioral pathology likely emerges during or after neurosensitive periods in which resource demands overwhelm system resources and the individual's ability to compensate using interregional activation fails. We are at the threshold of being able to chart autism and schizophrenia from the inside out. In so doing, the door is opened to the consideration of new therapeutics that are developed based upon molecular, synaptic, and systems targets common to both disorders.
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Affiliation(s)
- Nina de Lacy
- University of Washington and Seattle Children's Hospital, Seattle, Washington 98195, USA
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20
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Hall L, Kelley E. The contribution of epigenetics to understanding genetic factors in autism. AUTISM : THE INTERNATIONAL JOURNAL OF RESEARCH AND PRACTICE 2013; 18:872-81. [PMID: 24126868 DOI: 10.1177/1362361313503501] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Autism spectrum disorder is a grouping of neurodevelopmental disorders characterized by deficits in social communication and language, as well as by repetitive and stereotyped behaviors. While the environment is believed to play a role in the development of autism spectrum disorder, there is now strong evidence for a genetic link to autism. Despite such evidence, studies investigating a potential single-gene cause for autism, although insightful, have been highly inconclusive. A consideration of an epigenetic approach proves to be very promising in clarifying genetic factors involved in autism. The present article is intended to provide a review of key findings pertaining to epigenetics in autism in such a way that a broader audience of individuals who do not have a strong background in genetics may better understand this highly specific and scientific content. Epigenetics refers to non-permanent heritable changes that alter expression of genes without altering the DNA sequence itself and considers the role of environment in this modulation of gene expression. This review provides a brief description of epigenetic processes, highlights evidence in the literature of epigenetic dysregulation in autism, and makes use of noteworthy findings to illustrate how a consideration of epigenetic factors can deepen our understanding of the development of autism. Furthermore, this discussion will present a promising new way for moving forward in the investigation of genetic factors within autism.
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21
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Rose'meyer R. A review of the serotonin transporter and prenatal cortisol in the development of autism spectrum disorders. Mol Autism 2013; 4:37. [PMID: 24103554 PMCID: PMC3852299 DOI: 10.1186/2040-2392-4-37] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 09/13/2013] [Indexed: 01/28/2023] Open
Abstract
The diagnosis of autism spectrum disorder (ASD) during early childhood has a profound effect not only on young children but on their families. Aside from the physical and behavioural issues that need to be dealt with, there are significant emotional and financial costs associated with living with someone diagnosed with ASD. Understanding how autism occurs will assist in preparing families to deal with ASD, if not preventing or lessening its occurrence. Serotonin plays a vital role in the development of the brain during the prenatal and postnatal periods, yet very little is known about the serotonergic systems that affect children with ASD. This review seeks to provide an understanding of the biochemistry and physiological actions of serotonin and its termination of action through the serotonin reuptake transporter (SERT). Epidemiological studies investigating prenatal conditions that can increase the risk of ASD describe a number of factors which elevate plasma cortisol levels causing such symptoms during pregnancy such as hypertension, gestational diabetes and depression. Because cortisol plays an important role in driving dysregulation of serotonergic signalling through elevating SERT production in the developing brain, it is also necessary to investigate the physiological functions of cortisol, its action during gestation and metabolic syndromes.
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Affiliation(s)
- Roselyn Rose'meyer
- School of Medical Sciences, Griffith University, Gold Coast Campus, Parklands Drive, Southport, Queensland 4222, Australia.
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22
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Eapen V, Črnčec R, Walter A. Exploring Links between Genotypes, Phenotypes, and Clinical Predictors of Response to Early Intensive Behavioral Intervention in Autism Spectrum Disorder. Front Hum Neurosci 2013; 7:567. [PMID: 24062668 PMCID: PMC3769633 DOI: 10.3389/fnhum.2013.00567] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 08/26/2013] [Indexed: 12/27/2022] Open
Abstract
Autism spectrum disorder (ASD) is amongst the most familial of psychiatric disorders. Twin and family studies have demonstrated a monozygotic concordance rate of 70-90%, dizygotic concordance of around 10%, and more than a 20-fold increase in risk for first-degree relatives. Despite major advances in the genetics of autism, the relationship between different aspects of the behavioral and cognitive phenotype and their underlying genetic liability is still unclear. This is complicated by the heterogeneity of autism, which exists at both genetic and phenotypic levels. Given this heterogeneity, one method to find homogeneous entities and link these with specific genotypes would be to pursue endophenotypes. Evidence from neuroimaging, eye tracking, and electrophysiology studies supports the hypothesis that, building on genetic vulnerability, ASD emerges from a developmental cascade in which a deficit in attention to social stimuli leads to impaired interactions with primary caregivers. This results in abnormal development of the neurocircuitry responsible for social cognition, which in turn adversely affects later behavioral and functional domains dependent on these early processes, such as language development. Such a model begets a heterogeneous clinical phenotype, and is also supported by studies demonstrating better clinical outcomes with earlier treatment. Treatment response following intensive early behavioral intervention in ASD is also distinctly variable; however, relatively little is known about specific elements of the clinical phenotype that may predict response to current behavioral treatments. This paper overviews the literature regarding genotypes, phenotypes, and predictors of response to behavioral intervention in ASD and presents suggestions for future research to explore linkages between these that would enable better identification of, and increased treatment efficacy for, ASD.
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Affiliation(s)
- Valsamma Eapen
- Academic Unit of Child Psychiatry South West Sydney, South Western Sydney Local Health District, Liverpool, NSW, Australia
- School of Psychiatry, University of New South Wales, Sydney, NSW, Australia
| | - Rudi Črnčec
- School of Psychiatry, University of New South Wales, Sydney, NSW, Australia
| | - Amelia Walter
- Academic Unit of Child Psychiatry South West Sydney, South Western Sydney Local Health District, Liverpool, NSW, Australia
- School of Psychiatry, University of New South Wales, Sydney, NSW, Australia
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23
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Brief Report: social disability in autism spectrum disorder: results from Research Units on Pediatric Psychopharmacology (RUPP) Autism Network trials. J Autism Dev Disord 2013; 43:739-46. [PMID: 23104617 DOI: 10.1007/s10803-012-1689-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
There is growing interest in measuring social disability as a core element of autism spectrum disorders in medication trials. We conducted a secondary analysis on the Aberrant Behavior Checklist Social Withdrawal subscale using data from two federally-funded, multi-site, randomized trials with risperidone. Study 1 included 52 subjects assigned to placebo and 49 subjects to risperidone under double-blind conditions. Study 2 included 49 subjects assigned to risperidone only and 75 subjects assigned to risperidone plus parent training. After 8 weeks of treatment, all active treatments were superior to placebo (effect sizes ranging from 0.42 to 0.65). The findings suggest that the Social Withdrawal subscale may be a useful measure of social disability in acute treatment trials.
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Zuko A, Kleijer KTE, Oguro-Ando A, Kas MJH, van Daalen E, van der Zwaag B, Burbach JPH. Contactins in the neurobiology of autism. Eur J Pharmacol 2013; 719:63-74. [PMID: 23872404 DOI: 10.1016/j.ejphar.2013.07.016] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 06/18/2013] [Accepted: 07/01/2013] [Indexed: 12/21/2022]
Abstract
Autism is a disease of brain plasticity. Inspiring work of Willem Hendrik Gispen on neuronal plasticity has stimulated us to investigate gene defects in autism and the consequences for brain development. The central process in the pathogenesis of autism is local dendritic mRNA translation which is dependent on axodendritic communication. Hence, most autism-related gene products (i) are part of the protein synthesis machinery itself, (ii) are components of the mTOR signal transduction pathway, or (iii) shape synaptic activity and plasticity. Accordingly, prototype drugs have been recognized that interfere with these pathways. The contactin (CNTN) family of Ig cell adhesion molecules (IgCAMs) harbours at least three members that have genetically been implicated in autism: CNTN4, CNTN5, and CNTN6. In this chapter we review the genetic and neurobiological data underpinning their role in normal and abnormal development of brain systems, and the consequences for behavior. Although data on each of these CNTNs are far from complete, we tentatively conclude that these three contactins play roles in brain development in a critical phase of establishing brain systems and their plasticity. They modulate neuronal activities, such as neurite outgrowth, synaptogenesis, survival, guidance of projections and terminal branching of axons in forming neural circuits. Current research on these CNTNs concentrate on the neurobiological mechanism of their developmental functions. A future task will be to establish if proposed pharmacological strategies to counteract ASD-related symptomes can also be applied to reversal of phenotypes caused by genetic defects in these CNTN genes.
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Affiliation(s)
- Amila Zuko
- Department of Neuroscience and Pharmacology, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Kristel T E Kleijer
- Department of Neuroscience and Pharmacology, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Asami Oguro-Ando
- Department of Neuroscience and Pharmacology, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Martien J H Kas
- Department of Neuroscience and Pharmacology, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Emma van Daalen
- Department of Psychiatry, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - Bert van der Zwaag
- Department of Medical Genetics, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
| | - J Peter H Burbach
- Department of Neuroscience and Pharmacology, Brain Center Rudolf Magnus, UMC Medical Center Utrecht, 3584 CG Utrecht, The Netherlands.
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Kang JQ, Barnes G. A common susceptibility factor of both autism and epilepsy: functional deficiency of GABA A receptors. J Autism Dev Disord 2013; 43:68-79. [PMID: 22555366 DOI: 10.1007/s10803-012-1543-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Autism and epilepsy are common childhood neurological disorders with a great heterogeneity of clinical phenotypes as well as risk factors. There is a high co-morbidity of autism and epilepsy. The neuropathology of autism and epilepsy has similar histology implicating the processes of neurogenesis, neural migration, programmed cell death, and neurite outgrowth. Genetic advances have identified multiple molecules that participate in neural development, brain network connectivity, and synaptic function which are involved in the pathogenesis of autism and epilepsy. Mutations in GABA(A) receptor subunit have been frequently associated with epilepsy, autism, and other neuropsychiatric disorders. In this paper, we address the hypothesis that functional deficiency of GABAergic signaling is a potential common molecular mechanism underpinning the co-morbidity of autism and epilepsy.
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Affiliation(s)
- Jing-Qiong Kang
- Department of Neurology, Vanderbilt University Medical Center, 465 21st Ave, Nashville, TN 37232-8552, USA.
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26
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Lahiri DK, Sokol DK, Erickson C, Ray B, Ho CY, Maloney B. Autism as early neurodevelopmental disorder: evidence for an sAPPα-mediated anabolic pathway. Front Cell Neurosci 2013; 7:94. [PMID: 23801940 PMCID: PMC3689023 DOI: 10.3389/fncel.2013.00094] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 05/27/2013] [Indexed: 12/27/2022] Open
Abstract
Autism is a neurodevelopmental disorder marked by social skills and communication deficits and interfering repetitive behavior. Intellectual disability often accompanies autism. In addition to behavioral deficits, autism is characterized by neuropathology and brain overgrowth. Increased intracranial volume often accompanies this brain growth. We have found that the Alzheimer's disease (AD) associated amyloid-β precursor protein (APP), especially its neuroprotective processing product, secreted APP α, is elevated in persons with autism. This has led to the "anabolic hypothesis" of autism etiology, in which neuronal overgrowth in the brain results in interneuronal misconnections that may underlie multiple autism symptoms. We review the contribution of research in brain volume and of APP to the anabolic hypothesis, and relate APP to other proteins and pathways that have already been directly associated with autism, such as fragile X mental retardation protein, Ras small GTPase/extracellular signal-regulated kinase, and phosphoinositide 3 kinase/protein kinase B/mammalian target of rapamycin. We also present additional evidence of magnetic resonance imaging intracranial measurements in favor of the anabolic hypothesis. Finally, since it appears that APP's involvement in autism is part of a multi-partner network, we extend this concept into the inherently interactive realm of epigenetics. We speculate that the underlying molecular abnormalities that influence APP's contribution to autism are epigenetic markers overlaid onto potentially vulnerable gene sequences due to environmental influence.
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Affiliation(s)
- Debomoy K. Lahiri
- Department of Psychiatry, Indiana University School of MedicineIndianapolis, IN USA
- Laboratory of Medical and Molecular Genetics, Indiana University School of MedicineIndianapolis, IN, USA
- Institute of Psychiatric Research, Indiana University School of MedicineIndianapolis, IN, USA
| | - Deborah K. Sokol
- Department of Neurology, Indiana University School of MedicineIndianapolis, IN, USA
| | - Craig Erickson
- Cincinnati Children’s Hospital Medical CenterCincinnati, OH, USA
| | - Balmiki Ray
- Department of Psychiatry, Indiana University School of MedicineIndianapolis, IN USA
- Institute of Psychiatric Research, Indiana University School of MedicineIndianapolis, IN, USA
| | - Chang Y. Ho
- Department of Radiology and Imaging Sciences, Indiana University School of MedicineIndianapolis, IN, USA
| | - Bryan Maloney
- Department of Psychiatry, Indiana University School of MedicineIndianapolis, IN USA
- Institute of Psychiatric Research, Indiana University School of MedicineIndianapolis, IN, USA
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Penzes P, Buonanno A, Passafaro M, Sala C, Sweet RA. Developmental vulnerability of synapses and circuits associated with neuropsychiatric disorders. J Neurochem 2013; 126:165-82. [PMID: 23574039 DOI: 10.1111/jnc.12261] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 04/08/2013] [Indexed: 12/20/2022]
Abstract
Psychiatric and neurodegenerative disorders, including intellectual disability, autism spectrum disorders (ASD), schizophrenia (SZ), and Alzheimer's disease, pose an immense burden to society. Symptoms of these disorders become manifest at different stages of life: early childhood, adolescence, and late adulthood, respectively. Progress has been made in recent years toward understanding the genetic substrates, cellular mechanisms, brain circuits, and endophenotypes of these disorders. Multiple lines of evidence implicate excitatory and inhibitory synaptic circuits in the cortex and hippocampus as key cellular substrates of pathogenesis in these disorders. Excitatory/inhibitory balance--modulated largely by dopamine--critically regulates cortical network function, neural network activity (i.e. gamma oscillations) and behaviors associated with psychiatric disorders. Understanding the molecular underpinnings of synaptic pathology and neuronal network activity may thus provide essential insight into the pathogenesis of these disorders and can reveal novel drug targets to treat them. Here, we discuss recent genetic, neuropathological, and molecular studies that implicate alterations in excitatory and inhibitory synaptic circuits in the pathogenesis of psychiatric disorders across the lifespan.
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Affiliation(s)
- Peter Penzes
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
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Guthrie W, Swineford LB, Nottke C, Wetherby AM. Early diagnosis of autism spectrum disorder: stability and change in clinical diagnosis and symptom presentation. J Child Psychol Psychiatry 2013; 54:582-90. [PMID: 23078094 PMCID: PMC3556369 DOI: 10.1111/jcpp.12008] [Citation(s) in RCA: 174] [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] [Indexed: 11/28/2022]
Abstract
BACKGROUND Although a diagnosis of autism spectrum disorder (ASD) appears to be stable in children as young as age three, few studies have explored stability of a diagnosis in younger children. Predictive value of diagnostic tools for toddlers and patterns of symptom change are important considerations for clinicians making early diagnoses. Most findings come from high-risk samples, but reports on children screened in community settings are also needed. METHODS Stability of diagnosis and Autism Diagnostic Observation Schedule – Toddler Module (ADOS-T) classifications and scores was examined across two time points in a sample of 82 children identified through the FIRST WORDS Project.Children received two comprehensive diagnostic evaluations at average ages of 19.39 (SD = 2.12) and 36.89 (SD = 3.85) months. RESULTS Stability was 100% when confirming and ruling out a diagnosis of ASD based on a comprehensive diagnostic evaluation that included clinic and home observations,although diagnosis was initially deferred for 17% of the sample. Receiver Operating Characteristic curves revealed excellent sensitivity and acceptable specificity for the ADOS-T compared to concurrent diagnosis. Logistic regressions indicated good predictive value of initial ADOS-T scores for follow-up diagnosis. Finally, both ASD and Non-ASD children demonstrated a decrease in Social Affect scores (i.e.,improvement), whereas children with ASD demonstrated an increase in Restricted and Repetitive Behavior scores (i.e., worsening), changes that were accounted for by nonverbal developmental level in mixed model analyses. CONCLUSIONS Short-term stability was documented for children diagnosed at 19 months on average, although a minority of children initially showed unclear diagnostic presentations.Findings highlight utility of the ADOS-T in making early diagnoses and predicting follow-up diagnoses. Children with ASD demonstrated improvement in social communication behaviors and unfolding of repetitive behaviors, suggesting that certain early patterns of change in symptoms may be characteristic of ASD. KEYWORDS Autism spectrum disorder, developmental delay, diagnosis, development,assessment.
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Affiliation(s)
- Whitney Guthrie
- Autism Institute, College of Medicine, Florida State University, Tallahassee, FL, USA
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29
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Megremi AS. Is fever a predictive factor in the autism spectrum disorders? Med Hypotheses 2013; 80:391-8. [PMID: 23394936 DOI: 10.1016/j.mehy.2013.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 01/04/2013] [Accepted: 01/05/2013] [Indexed: 02/08/2023]
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Stamou M, Streifel KM, Goines PE, Lein PJ. Neuronal connectivity as a convergent target of gene × environment interactions that confer risk for Autism Spectrum Disorders. Neurotoxicol Teratol 2013; 36:3-16. [PMID: 23269408 PMCID: PMC3610799 DOI: 10.1016/j.ntt.2012.12.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 11/12/2012] [Accepted: 12/17/2012] [Indexed: 11/21/2022]
Abstract
Evidence implicates environmental factors in the pathogenesis of Autism Spectrum Disorders (ASD). However, the identity of specific environmental chemicals that influence ASD risk, severity or treatment outcome remains elusive. The impact of any given environmental exposure likely varies across a population according to individual genetic substrates, and this increases the difficulty of identifying clear associations between exposure and ASD diagnoses. Heritable genetic vulnerabilities may amplify adverse effects triggered by environmental exposures if genetic and environmental factors converge to dysregulate the same signaling systems at critical times of development. Thus, one strategy for identifying environmental risk factors for ASD is to screen for environmental factors that modulate the same signaling pathways as ASD susceptibility genes. Recent advances in defining the molecular and cellular pathology of ASD point to altered patterns of neuronal connectivity in the developing brain as the neurobiological basis of these disorders. Studies of syndromic ASD and rare highly penetrant mutations or CNVs in ASD suggest that ASD risk genes converge on several major signaling pathways linked to altered neuronal connectivity in the developing brain. This review briefly summarizes the evidence implicating dysfunctional signaling via Ca(2+)-dependent mechanisms, extracellular signal-regulated kinases (ERK)/phosphatidylinositol-3-kinases (PI3K) and neuroligin-neurexin-SHANK as convergent molecular mechanisms in ASD, and then discusses examples of environmental chemicals for which there is emerging evidence of their potential to interfere with normal neuronal connectivity via perturbation of these signaling pathways.
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Affiliation(s)
- Marianna Stamou
- Department of Molecular Biosciences, University of California at Davis School of Veterinary Medicine, Davis CA, 95616, United States
| | - Karin M. Streifel
- Department of Molecular Biosciences, University of California at Davis School of Veterinary Medicine, Davis CA, 95616, United States
| | - Paula E. Goines
- Department of Molecular Biosciences, University of California at Davis School of Veterinary Medicine, Davis CA, 95616, United States
| | - Pamela J. Lein
- Department of Molecular Biosciences, University of California at Davis School of Veterinary Medicine, Davis CA, 95616, United States
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Maternal conditions and perinatal characteristics associated with autism spectrum disorder and intellectual disability. PLoS One 2013; 8:e50963. [PMID: 23308096 PMCID: PMC3538698 DOI: 10.1371/journal.pone.0050963] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 10/29/2012] [Indexed: 01/29/2023] Open
Abstract
Background As well as being highly comorbid conditions, autism spectrum disorders (ASD) and intellectual disability (ID) share a number of clinically-relevant phenomena. This raises questions about similarities and overlap in diagnosis and aetiological pathways that may exist for both conditions. Aims To examine maternal conditions and perinatal factors for children diagnosed with an ASD, with or without ID, and children with ID of unknown cause, compared with unaffected children. Methods The study population comprised all live singleton births in Western Australia (WA) between January 1984 and December 1999 (N = 383,153). Univariate and multivariate multinomial logistic regression models were applied using a blocked modelling approach to assess the effect of maternal conditions, sociodemographic factors, labour and delivery characteristics and neonatal outcomes. Results In univariate analyses mild-moderate ID was associated with pregnancy hypertension, asthma, urinary tract infection, some types of ante-partum haemorrhage, any type of preterm birth, elective C-sections, breech presentation, poor fetal growth and need for resuscitation at birth, with all factors showing an increased risk. Severe ID was positively associated with poor fetal growth and need for resuscitation, as well as any labour or delivery complication. In the multivariate analysis no maternal conditions or perinatal factors were associated with an increased risk of ASD without ID. However, pregnancy hypertension and small head circumference were associated with a reduced risk (OR = 0.64, 95% CI: 0.43, 0.94; OR = 0.58, 95% CI: 0.34, 0.96, respectively). For ASD with ID, threatened abortion before 20 weeks gestation and poor fetal growth were associated with an increased risk. Conclusion Findings show that indicators of a poor intrauterine environment are associated with an elevated risk of ID, while for ASD, and particularly ASD without ID, the associations are much weaker. As such, these findings highlight the importance of accounting for the absence or presence of ID when examining ASD, if we are to improve our understanding of the causal pathways associated with these conditions.
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Berry A, Borgi M, Francia N, Alleva E, Cirulli F. Use of assistance and therapy dogs for children with autism spectrum disorders: a critical review of the current evidence. J Altern Complement Med 2012; 19:73-80. [PMID: 22978246 DOI: 10.1089/acm.2011.0835] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Autism spectrum disorders (ASD) are characterized by deficits in social reciprocity and communication, and by unusually restricted, repetitive behaviors. Intervention strategies based on the exploitation of the emotional aspects of human-dog relationships hold the potential to overcome the difficulty of subjects with ASD to relate and interact effectively with others, targeting core symptoms of this disorder. METHODS This review summarizes the results of six published studies on the effects of brief interactions with dogs and the effects of introducing dogs in families with a child diagnosed with ASD, with an emphasis on social behaviors and language use. Furthermore, the possible mechanisms responsible for the beneficial effects observed are discussed. CONCLUSIONS Although the studies described here are encouraging, further research with better designs and using larger samples is needed to strengthen translation of such interventions to the clinic. In addition, potential applications of analyzing child-dog interactions are highlighted to screen for early signs of the disorder.
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Affiliation(s)
- Alessandra Berry
- Section of Behavioral Neurosciences, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy
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Li X, Zou H, Brown WT. Genes associated with autism spectrum disorder. Brain Res Bull 2012; 88:543-52. [PMID: 22688012 DOI: 10.1016/j.brainresbull.2012.05.017] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 05/31/2012] [Indexed: 01/06/2023]
Abstract
Autism spectrum disorder (ASD) is a heterogeneous grouping of neurodevelopmental disorders characterized by impairment in social interaction, verbal communication and repetitive/stereotypic behaviors. Much evidence suggests that ASD is multifactorial with a strong genetic basis, but the underlying mechanisms are far from clear. Recent advances in genetic technologies are beginning to shed light on possible etiologies of ASD. This review discusses current evidence for several widely studied candidate ASD genes, as well as various rare genes that supports their relationship to the etiology of ASD. The majority of the data are based on molecular, cytogenetic, linkage and association studies of autistic subjects, but newer methods, including whole-exome sequencing, are also beginning to make significant contributions to our understanding of autism.
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Affiliation(s)
- Xiaohong Li
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, New York, NY 10314, United States.
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Huang CC, Chen CH. Role of GABAergic signaling and the GABAA receptor subunit gene cluster at 15q11-q13 in autism spectrum disorders, schizophrenia, and heroin addiction. Tzu Chi Med J 2012. [DOI: 10.1016/j.tcmj.2012.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Newschaffer CJ, Croen LA, Fallin MD, Hertz-Picciotto I, Nguyen DV, Lee NL, Berry CA, Farzadegan H, Hess HN, Landa RJ, Levy SE, Massolo ML, Meyerer SC, Mohammed SM, Oliver MC, Ozonoff S, Pandey J, Schroeder A, Shedd-Wise KM. Infant siblings and the investigation of autism risk factors. J Neurodev Disord 2012; 4:7. [PMID: 22958474 PMCID: PMC3436647 DOI: 10.1186/1866-1955-4-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Accepted: 04/18/2012] [Indexed: 12/31/2022] Open
Abstract
Infant sibling studies have been at the vanguard of autism spectrum disorders (ASD) research over the past decade, providing important new knowledge about the earliest emerging signs of ASD and expanding our understanding of the developmental course of this complex disorder. Studies focused on siblings of children with ASD also have unrealized potential for contributing to ASD etiologic research. Moving targeted time of enrollment back from infancy toward conception creates tremendous opportunities for optimally studying risk factors and risk biomarkers during the pre-, peri- and neonatal periods. By doing so, a traditional sibling study, which already incorporates close developmental follow-up of at-risk infants through the third year of life, is essentially reconfigured as an enriched-risk pregnancy cohort study. This review considers the enriched-risk pregnancy cohort approach of studying infant siblings in the context of current thinking on ASD etiologic mechanisms. It then discusses the key features of this approach and provides a description of the design and implementation strategy of one major ASD enriched-risk pregnancy cohort study: the Early Autism Risk Longitudinal Investigation (EARLI).
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Affiliation(s)
- Craig J Newschaffer
- Department of Epidemiology and Biostatistics, Drexel School of Public Health, 1505 Race Street, Mail Stop 1033, Philadelphia, PA 19102, USA
| | - Lisa A Croen
- Kaiser Permanente Division of Research, 2000 Broadway, Oakland, CA 94612, USA
| | - M Daniele Fallin
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Irva Hertz-Picciotto
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Danh V Nguyen
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Nora L Lee
- Department of Epidemiology and Biostatistics, Drexel School of Public Health, 1505 Race Street, Mail Stop 1033, Philadelphia, PA 19102, USA
| | - Carmen A Berry
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Homayoon Farzadegan
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - H Nicole Hess
- Kaiser Permanente San Jose Medical Center, 6620 Via Del Oro, San Jose, CA 95119, USA
| | - Rebecca J Landa
- Kennedy Krieger Institute, 3901 Greenspring Avenue, 2nd Floor, Baltimore, MD 21211, USA
| | - Susan E Levy
- Center for Autism Research, The Children's Hospital of Philadelphia, 3535 Market Street, Suite 860, Philadelphia, PA 19104, USA
| | - Maria L Massolo
- Kaiser Permanente Division of Research, 2000 Broadway, Oakland, CA 94612, USA
| | - Stacey C Meyerer
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Sandra M Mohammed
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - McKenzie C Oliver
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Sally Ozonoff
- The MIND Institute, UC Davis Medical Center, 2825 50th Street, Sacramento, CA 95817, USA
| | - Juhi Pandey
- Center for Autism Research, The Children's Hospital of Philadelphia, 3535 Market Street, Suite 860, Philadelphia, PA 19104, USA
| | - Adam Schroeder
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Kristine M Shedd-Wise
- Department of Public Health Sciences, University of California, Davis, CA 95616, USA
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Whole-exome sequencing and homozygosity analysis implicate depolarization-regulated neuronal genes in autism. PLoS Genet 2012; 8:e1002635. [PMID: 22511880 PMCID: PMC3325173 DOI: 10.1371/journal.pgen.1002635] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 02/21/2012] [Indexed: 12/13/2022] Open
Abstract
Although autism has a clear genetic component, the high genetic heterogeneity of the disorder has been a challenge for the identification of causative genes. We used homozygosity analysis to identify probands from nonconsanguineous families that showed evidence of distant shared ancestry, suggesting potentially recessive mutations. Whole-exome sequencing of 16 probands revealed validated homozygous, potentially pathogenic recessive mutations that segregated perfectly with disease in 4/16 families. The candidate genes (UBE3B, CLTCL1, NCKAP5L, ZNF18) encode proteins involved in proteolysis, GTPase-mediated signaling, cytoskeletal organization, and other pathways. Furthermore, neuronal depolarization regulated the transcription of these genes, suggesting potential activity-dependent roles in neurons. We present a multidimensional strategy for filtering whole-exome sequence data to find candidate recessive mutations in autism, which may have broader applicability to other complex, heterogeneous disorders.
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O’Roak BJ, Vives L, Girirajan S, Karakoc E, Krumm N, Coe BP, Levy R, Ko A, Lee C, Smith JD, Turner EH, Stanaway IB, Vernot B, Malig M, Baker C, Reilly B, Akey JM, Borenstein E, Rieder MJ, Nickerson DA, Bernier R, Shendure J, Eichler EE. Sporadic autism exomes reveal a highly interconnected protein network of de novo mutations. Nature 2012; 485:246-50. [PMID: 22495309 PMCID: PMC3350576 DOI: 10.1038/nature10989] [Citation(s) in RCA: 1563] [Impact Index Per Article: 130.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 02/23/2012] [Indexed: 02/08/2023]
Abstract
It is well established that autism spectrum disorders (ASD) have a strong genetic component; however, for at least 70% of cases, the underlying genetic cause is unknown. Under the hypothesis that de novo mutations underlie a substantial fraction of the risk for developing ASD in families with no previous history of ASD or related phenotypes--so-called sporadic or simplex families--we sequenced all coding regions of the genome (the exome) for parent-child trios exhibiting sporadic ASD, including 189 new trios and 20 that were previously reported. Additionally, we also sequenced the exomes of 50 unaffected siblings corresponding to these new (n = 31) and previously reported trios (n = 19), for a total of 677 individual exomes from 209 families. Here we show that de novo point mutations are overwhelmingly paternal in origin (4:1 bias) and positively correlated with paternal age, consistent with the modest increased risk for children of older fathers to develop ASD. Moreover, 39% (49 of 126) of the most severe or disruptive de novo mutations map to a highly interconnected β-catenin/chromatin remodelling protein network ranked significantly for autism candidate genes. In proband exomes, recurrent protein-altering mutations were observed in two genes: CHD8 and NTNG1. Mutation screening of six candidate genes in 1,703 ASD probands identified additional de novo, protein-altering mutations in GRIN2B, LAMC3 and SCN1A. Combined with copy number variant (CNV) data, these results indicate extreme locus heterogeneity but also provide a target for future discovery, diagnostics and therapeutics.
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Affiliation(s)
- Brian J. O’Roak
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Laura Vives
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Santhosh Girirajan
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Emre Karakoc
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Nik Krumm
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Bradley P. Coe
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Roie Levy
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Arthur Ko
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Choli Lee
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Joshua D. Smith
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Emily H. Turner
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Ian B. Stanaway
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Benjamin Vernot
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Maika Malig
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Carl Baker
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Beau Reilly
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - Joshua M. Akey
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Elhanan Borenstein
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
- Department of Computer Science and Engineering, University of Washington, Seattle, WA, USA
- Santa Fe Institute, Santa Fe, NM, USA
| | - Mark J. Rieder
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Deborah A. Nickerson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Raphael Bernier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - Jay Shendure
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Evan E. Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
- Howard Hughes Medical Institute, Seattle, WA, USA
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Murji A, Proctor LK, Paterson AD, Chitayat D, Weksberg R, Kingdom J. Male sex bias in placental dysfunction. Am J Med Genet A 2012; 158A:779-83. [PMID: 22407866 DOI: 10.1002/ajmg.a.35250] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 12/15/2011] [Indexed: 01/23/2023]
Abstract
Several reports suggest a male fetal preponderance in a variety of complications of pregnancy attributable to severe placental dysfunction (SPD). However, the underlying mechanisms remain unknown. Our primary objective was to explore the relationship between fetal sex and the spectrum of conditions implicated in abnormal placentation. We identified singleton pregnancies with a fetus delivered between 20 + 0 and 32 + 6 weeks of gestation with one or more pregnancy complications attributed to SPD (severe pre-eclampsia, intra-uterine fetal death, intra-uterine growth restriction, abnormal Doppler studies, abruption) at a single institution between 1999 and 2007. Pedigrees of index cases were created to define the relationship between fetal sex and the risk of SPD. We identified 132 index cases, 97/132 (73%) were male. Eighty-four index cases had a total of 133 sibs, of which 37/133 (28%) were affected with SPD (22 male, 15 female). A male sex preponderance persisted across all manifestations of PD in index cases with sibs. In families with the absence of maternal chronic hypertension (cHTN; n = 70), the index case was 5.9 (95% CI 2.28-16.15; P <0.001) times more likely to be male and most (12/14) affected sibs of male index cases were male, while female index cases had no affected sibs. Our results confirm a male fetal sex preponderance in SPD. In a subgroup analysis of families without cHTN, a significant male bias was found to extend to sibs of index cases. This suggests a potential genetic mechanism predisposing the male fetus to abnormal placental development.
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Affiliation(s)
- Ally Murji
- Maternal-Fetal Medicine Division, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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Networks of neuronal genes affected by common and rare variants in autism spectrum disorders. PLoS Genet 2012; 8:e1002556. [PMID: 22412387 PMCID: PMC3297570 DOI: 10.1371/journal.pgen.1002556] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 01/11/2012] [Indexed: 11/19/2022] Open
Abstract
Autism spectrum disorders (ASD) are neurodevelopmental disorders with phenotypic and genetic heterogeneity. Recent studies have reported rare and de novo mutations in ASD, but the allelic architecture of ASD remains unclear. To assess the role of common and rare variations in ASD, we constructed a gene co-expression network based on a widespread survey of gene expression in the human brain. We identified modules associated with specific cell types and processes. By integrating known rare mutations and the results of an ASD genome-wide association study (GWAS), we identified two neuronal modules that are perturbed by both rare and common variations. These modules contain highly connected genes that are involved in synaptic and neuronal plasticity and that are expressed in areas associated with learning and memory and sensory perception. The enrichment of common risk variants was replicated in two additional samples which include both simplex and multiplex families. An analysis of the combined contribution of common variants in the neuronal modules revealed a polygenic component to the risk of ASD. The results of this study point toward contribution of minor and major perturbations in the two sub-networks of neuronal genes to ASD risk.
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Losh M, Martin GE, Klusek J, Hogan-Brown AL. Pragmatic Language in autism and fragile X syndrome: Genetic and clinical applications. PERSPECTIVES ON LANGUAGE LEARNING AND EDUCATION 2012; 19:48-55. [PMID: 24660047 PMCID: PMC3961489 DOI: 10.1044/lle19.2.48] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Evidence suggests a strong genetic basis to autism. Our research program focuses on identifying genetically meaningful phenotypes in autism, through family-genetic and cross-population methods, with a particular focus on language and social phenotypes that have been shown to aggregate in families of individuals with autism. In this article, we discuss recent findings from family study research implicating particular language and personality features as markers for genetic liability to autism and fragile X syndrome and FMR1-related variation in relatives. We conclude with consideration of the clinical implications of such findings.
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Affiliation(s)
- Molly Losh
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University
| | - Gary E. Martin
- FPG Child Development Institute, University of North Carolina at Chapel Hill
- Division of Speech and Hearing Sciences, Allied Health Sciences, University of North Carolina at Chapel Hill
| | - Jessica Klusek
- FPG Child Development Institute, University of North Carolina at Chapel Hill
- Division of Speech and Hearing Sciences, Allied Health Sciences, University of North Carolina at Chapel Hill
| | - Abigail L. Hogan-Brown
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University
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Nagano R, Akanuma H, Qin XY, Imanishi S, Toyoshiba H, Yoshinaga J, Ohsako S, Sone H. Multi-parametric profiling network based on gene expression and phenotype data: a novel approach to developmental neurotoxicity testing. Int J Mol Sci 2011; 13:187-207. [PMID: 22312247 PMCID: PMC3269681 DOI: 10.3390/ijms13010187] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/14/2011] [Accepted: 11/30/2011] [Indexed: 12/31/2022] Open
Abstract
The establishment of more efficient approaches for developmental neurotoxicity testing (DNT) has been an emerging issue for children’s environmental health. Here we describe a systematic approach for DNT using the neuronal differentiation of mouse embryonic stem cells (mESCs) as a model of fetal programming. During embryoid body (EB) formation, mESCs were exposed to 12 chemicals for 24 h and then global gene expression profiling was performed using whole genome microarray analysis. Gene expression signatures for seven kinds of gene sets related to neuronal development and neuronal diseases were selected for further analysis. At the later stages of neuronal cell differentiation from EBs, neuronal phenotypic parameters were determined using a high-content image analyzer. Bayesian network analysis was then performed based on global gene expression and neuronal phenotypic data to generate comprehensive networks with a linkage between early events and later effects. Furthermore, the probability distribution values for the strength of the linkage between parameters in each network was calculated and then used in principal component analysis. The characterization of chemicals according to their neurotoxic potential reveals that the multi-parametric analysis based on phenotype and gene expression profiling during neuronal differentiation of mESCs can provide a useful tool to monitor fetal programming and to predict developmentally neurotoxic compounds.
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Affiliation(s)
- Reiko Nagano
- Health Risk Research Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan; E-Mails: (R.N.); (H.A.); (X.-Y.Q.); (H.T.)
| | - Hiromi Akanuma
- Health Risk Research Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan; E-Mails: (R.N.); (H.A.); (X.-Y.Q.); (H.T.)
| | - Xian-Yang Qin
- Health Risk Research Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan; E-Mails: (R.N.); (H.A.); (X.-Y.Q.); (H.T.)
- Department of Environmental Studies, Graduate School of Frontier Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 270-8563, Japan; E-Mail:
| | - Satoshi Imanishi
- Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan; E-Mails: (S.I.); (S.O.)
| | - Hiroyoshi Toyoshiba
- Health Risk Research Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan; E-Mails: (R.N.); (H.A.); (X.-Y.Q.); (H.T.)
| | - Jun Yoshinaga
- Department of Environmental Studies, Graduate School of Frontier Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 270-8563, Japan; E-Mail:
| | - Seiichiroh Ohsako
- Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan; E-Mails: (S.I.); (S.O.)
| | - Hideko Sone
- Health Risk Research Section, Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan; E-Mails: (R.N.); (H.A.); (X.-Y.Q.); (H.T.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +81-29-850-2464; Fax: +81-29-850-2546
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Abstract
Autism is an early onset neurodevelopmental disorder characterized by disruption of early social interaction. Although the social disability of autism remains the central defining feature of the condition, mechanisms that might account for this disability remain poorly understood. This paper briefly reviews some aspects of the social deficit in autism focusing on new approaches to characterizing social information processing problems, potential brain mechanisms, and theoretical models of the disorder. It will touch on aspects of specific social processes that appear to develop in unusual ways in autism including facial perception, joint attention, and social information processing. The importance of adopting more ecologically valid methods and for integrating the various approaches in deriving new models for social deficits in autism will be highlighted. Future research should build on the emerging synergy of different aspects of social neuroscience.
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Affiliation(s)
- Fred R Volkmar
- Child Study Center, Yale University, New Haven, CT 06520, USA.
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44
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A MECP2 missense mutation within the MBD domain in a Brazilian male with autistic disorder. Brain Dev 2011; 33:807-9. [PMID: 21600714 DOI: 10.1016/j.braindev.2011.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 04/27/2011] [Accepted: 04/28/2011] [Indexed: 11/23/2022]
Abstract
Point mutations and genomic rearrangements in the MECP2 gene are the major cause of Rett syndrome (RTT), a pervasive developmental disorder affecting almost exclusively females. MECP2 mutations were also identified in patients with autism without RTT. In this study, we present a mutational and gene dosage analysis of the MECP2 in a cohort of 60 Brazilian males with autistic features but not RTT. No duplication or deletion was identified. Sequencing analysis, however, revealed four MECP2 sequence variations. Three of them were previously discussed as non disease causing mutations and one mutation (p.T160S) was novel. It affects a highly conserved amino acid located within the MBD domain, a region of the protein involved in specific recognition and interaction with methylated CpG dinucleotides. The p.T160S variation was not found in the control sample. This mutation may represent a potential genetic factor for autistic phenotype and should be object of further studies.
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Aldridge K, George ID, Cole KK, Austin JR, Takahashi TN, Duan Y, Miles JH. Facial phenotypes in subgroups of prepubertal boys with autism spectrum disorders are correlated with clinical phenotypes. Mol Autism 2011; 2:15. [PMID: 21999758 PMCID: PMC3212884 DOI: 10.1186/2040-2392-2-15] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 10/14/2011] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND The brain develops in concert and in coordination with the developing facial tissues, with each influencing the development of the other and sharing genetic signaling pathways. Autism spectrum disorders (ASDs) result from alterations in the embryological brain, suggesting that the development of the faces of children with ASD may result in subtle facial differences compared to typically developing children. In this study, we tested two hypotheses. First, we asked whether children with ASD display a subtle but distinct facial phenotype compared to typically developing children. Second, we sought to determine whether there are subgroups of facial phenotypes within the population of children with ASD that denote biologically discrete subgroups. METHODS The 3dMD cranial System was used to acquire three-dimensional stereophotogrammetric images for our study sample of 8- to 12-year-old boys diagnosed with essential ASD (n = 65) and typically developing boys (n = 41) following approved Institutional Review Board protocols. Three-dimensional coordinates were recorded for 17 facial anthropometric landmarks using the 3dMD Patient software. Statistical comparisons of facial phenotypes were completed using Euclidean Distance Matrix Analysis and Principal Coordinates Analysis. Data representing clinical and behavioral traits were statistically compared among groups by using χ2 tests, Fisher's exact tests, Kolmogorov-Smirnov tests and Student's t-tests where appropriate. RESULTS First, we found that there are significant differences in facial morphology in boys with ASD compared to typically developing boys. Second, we also found two subgroups of boys with ASD with facial morphology that differed from the majority of the boys with ASD and the typically developing boys. Furthermore, membership in each of these distinct subgroups was correlated with particular clinical and behavioral traits. CONCLUSIONS Boys with ASD display a facial phenotype distinct from that of typically developing boys, which may reflect alterations in the prenatal development of the brain. Subgroups of boys with ASD defined by distinct facial morphologies correlated with clinical and behavioral traits, suggesting potentially different etiologies and genetic differences compared to the larger group of boys with ASD. Further investigations into genes involved in neurodevelopment and craniofacial development of these subgroups will help to elucidate the causes and significance of these subtle facial differences.
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Affiliation(s)
- Kristina Aldridge
- Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, One Hospital Dr, M309 Med Sci Bldg, Columbia, MO 65212, USA
- Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, 205 Portland St, Columbia, MO 65211, USA
| | - Ian D George
- Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, One Hospital Dr, M309 Med Sci Bldg, Columbia, MO 65212, USA
| | - Kimberly K Cole
- Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, One Hospital Dr, M309 Med Sci Bldg, Columbia, MO 65212, USA
| | - Jordan R Austin
- Department of Pathology and Anatomical Sciences, University of Missouri School of Medicine, One Hospital Dr, M309 Med Sci Bldg, Columbia, MO 65212, USA
| | - T Nicole Takahashi
- Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, 205 Portland St, Columbia, MO 65211, USA
| | - Ye Duan
- Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, 205 Portland St, Columbia, MO 65211, USA
- Department of Computer Science, University of Missouri, 209 Engineering Building West, Columbia, MO 65211, USA
| | - Judith H Miles
- Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, 205 Portland St, Columbia, MO 65211, USA
- Department of Child Health, University of Missouri School of Medicine, One Hospital Dr, N712, Columbia, MO 65212, USA
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46
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Warren Z, Vehorn A, Dohrmann E, Nicholson A, Sutcliffe JS, Veenstra-Vanderweele J. Accuracy of phenotyping children with autism based on parent report: what specifically do we gain phenotyping "rapidly"? Autism Res 2011; 5:31-8. [PMID: 21972233 DOI: 10.1002/aur.230] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 08/17/2011] [Accepted: 08/17/2011] [Indexed: 11/09/2022]
Abstract
Autism spectrum disorder (ASD) is considered among the most heritable of all neurodevelopmental and psychiatric disorders, but identification of etiologically significant genetic markers and risk variants has been hampered by a lack of sufficiently large samples. Rapid phenotyping procedures, where self-report measures are used instead of extensive clinical assessment, have been proposed as methods for amassing large genetic databases due to their hypothesized time-efficiency and affordability. We assessed the diagnostic accuracy of potential rapid phenotyping procedures using the Social Communication Questionnaire and the Social Responsiveness Scale in a sample of 333 children who also received extensive phenotypic assessments. While the rapid phenotyping measures were able to accurately identify a large number of children with ASD, they also frequently failed to differentiate children with ASD from children with other complex neurobehavioral profiles. These data support the continued need of expert clinical validation in combination with rapid phenotyping procedures in order to accurately amass large-scale genetic collections of children with ASD.
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Affiliation(s)
- Zachary Warren
- Department of Pediatrics, Vanderbilt University, Nashville, Tennessee, USA.
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47
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Abstract
Autism is an etiologically and clinically heterogeneous group of disorders, diagnosed solely by the complex behavioral phenotype. On the basis of the high-heritability index, geneticists are confident that autism will be the first behavioral disorder for which the genetic basis can be well established. Although it was initially assumed that major genome-wide and candidate gene association studies would lead most directly to common autism genes, progress has been slow. Rather, most discoveries have come from studies of known genetic disorders associated with the behavioral phenotype. New technology, especially array chromosomal genomic hybridization, has both increased the identification of putative autism genes and raised to approximately 25%, the percentage of children for whom an autism-related genetic change can be identified. Incorporating clinical geneticists into the diagnostic and autism research arenas is vital to the field. Interpreting this new technology and deciphering autism's genetic montage require the skill set of the clinical geneticist including knowing how to acquire and interpret family pedigrees, how to analyze complex morphologic, neurologic, and medical phenotypes, sorting out heterogeneity, developing rational genetic models, and designing studies. The current emphasis on deciphering autism spectrum disorders has accelerated the field of neuroscience and demonstrated the necessity of multidisciplinary research that must include clinical geneticists both in the clinics and in the design and implementation of basic, clinical, and translational research.
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48
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Barbaro J, Ridgway L, Dissanayake C. Developmental surveillance of infants and toddlers by maternal and child health nurses in an Australian community-based setting: promoting the early identification of autism spectrum disorders. J Pediatr Nurs 2011; 26:334-47. [PMID: 21726784 DOI: 10.1016/j.pedn.2010.04.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 03/04/2010] [Accepted: 04/13/2010] [Indexed: 10/19/2022]
Abstract
Although signs of autism spectrum disorders (ASDs) are evident during the first year of life, few children are diagnosed prior to 3 years. The objective in this article is to highlight the role that primary health care professionals can play in the early identification of ASDs by briefly outlining the successful implementation of The Social Attention and Communication Study. Maternal and child health nurses were trained on the early signs of ASDs, which enabled them to identify these children prior to 2 years. The training procedure used will be outlined, and the early signs that were monitored will be explained in detail. It is recommended that routine monitoring for ASDs in infancy and toddlerhood become standard practice among all primary health care professionals.
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Affiliation(s)
- Josephine Barbaro
- Olga Tennison Autism Research Centre, School of Psychological Science, La Trobe University, Bundoora, Victoria, Australia
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49
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Heo Y, Zhang Y, Gao D, Miller VM, Lawrence DA. Aberrant immune responses in a mouse with behavioral disorders. PLoS One 2011; 6:e20912. [PMID: 21799730 PMCID: PMC3140472 DOI: 10.1371/journal.pone.0020912] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 05/16/2011] [Indexed: 12/25/2022] Open
Abstract
BTBR T+tf/J (BTBR) mice have recently been reported to have behaviors that resemble those of autistic individuals, in that this strain has impairments in social interactions and a restricted repetitive and stereotyped pattern of behaviors. Since immune responses, including autoimmune responses, are known to affect behavior, and individuals with autism have aberrant immune activities, we evaluated the immune system of BTBR mice, and compared their immunity and degree of neuroinflammation with that of C57BL/6 (B6) mice, a highly social control strain, and with F1 offspring. Mice were assessed at postnatal day (pnd) 21 and after behavioral analysis at pnd70. BTBR mice had significantly higher amounts of serum IgG and IgE, of IgG anti-brain antibodies (Abs), and of IgG and IgE deposited in the brain, elevated expression of cytokines, especially IL-33 IL-18, and IL-1β in the brain, and an increased proportion of MHC class II-expressing microglia compared to B6 mice. The F1 mice had intermediate levels of Abs and cytokines as well as social activity. The high Ab levels of BTBR mice are in agreement with their increased numbers of CD40(hi)/I-A(hi) B cells and IgG-secreting B cells. Upon immunization with KLH, the BTBR mice produced 2-3 times more anti-KLH Abs than B6 mice. In contrast to humoral immunity, BTBR mice are significantly more susceptible to listeriosis than B6 or BALB/c mice. The Th2-like immune profile of the BTBR mice and their constitutive neuroinflammation suggests that an autoimmune profile is implicated in their aberrant behaviors, as has been suggested for some humans with autism.
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Affiliation(s)
- Yong Heo
- College of Natural Sciences, Catholic University of Daegu, Kyongsan-si, Republic of Korea
| | - Yubin Zhang
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- University at Albany School of Public Health, Albany, New York, United States of America
| | - Donghong Gao
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Veronica M. Miller
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - David A. Lawrence
- Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- University at Albany School of Public Health, Albany, New York, United States of America
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50
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Scherer SW, Dawson G. Risk factors for autism: translating genomic discoveries into diagnostics. Hum Genet 2011; 130:123-48. [PMID: 21701786 DOI: 10.1007/s00439-011-1037-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Accepted: 06/06/2011] [Indexed: 01/06/2023]
Abstract
Autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in communication and reciprocal social interaction, and the presence of restricted and repetitive behaviors. The spectrum of autistic features is variable, with severity of symptoms ranging from mild to severe, sometimes with poor clinical outcomes. Twin and family studies indicate a strong genetic basis for ASD susceptibility. Recent progress in defining rare highly penetrant mutations and copy number variations as ASD risk factors has prompted early uptake of these research findings into clinical diagnostics, with microarrays becoming a 'standard of care' test for any ASD diagnostic work-up. The ever-changing landscape of the generation of genomic data coupled with the vast heterogeneity in cause and expression of ASDs (further influenced by issues of penetrance, variable expressivity, multigenic inheritance and ascertainment) creates complexity that demands careful consideration of how to apply this knowledge. Here, we discuss the scientific, ethical, policy and communication aspects of translating the new discoveries into clinical and diagnostic tools for promoting the well-being of individuals and families with ASDs.
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Affiliation(s)
- Stephen W Scherer
- McLaughlin Centre and The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, ON M5G 1L7, Canada.
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