1
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Liu X, Sun X, Guo C, Huang ZF, Chen YR, Feng FM, Wu LJ, Chen WX. Untargeted urine metabolomics and machine learning provide potential metabolic signatures in children with autism spectrum disorder. Front Psychiatry 2024; 15:1261617. [PMID: 38445087 PMCID: PMC10912307 DOI: 10.3389/fpsyt.2024.1261617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 01/19/2024] [Indexed: 03/07/2024] Open
Abstract
Background Complementary to traditional biostatistics, the integration of untargeted urine metabolomic profiling with Machine Learning (ML) has the potential to unveil metabolic profiles crucial for understanding diseases. However, the application of this approach in autism remains underexplored. Our objective was to delve into the metabolic profiles of autism utilizing a comprehensive untargeted metabolomics platform coupled with ML. Methods Untargeted metabolomics quantification (UHPLC/Q-TOF-MS) was performed for urine analysis. Feature selection was conducted using Lasso regression, and logistic regression, support vector machine, random forest, and extreme gradient boosting were utilized for significance stratification. Pathway enrichment analysis was performed to identify metabolic pathways associated with autism. Results A total of 52 autistic children and 40 typically developing children were enrolled. Lasso regression identified ninety-two urinary metabolites that significantly differed between the two groups. Distinct metabolites, such as prostaglandin E2, phosphonic acid, lysine, threonine, and phenylalanine, were revealed to be associated with autism through the application of four different ML methods (p<0.05). The alterations observed in the phosphatidylinositol and inositol phosphate metabolism pathways were linked to the pathophysiology of autism (p<0.05). Conclusion Significant urinary metabolites, including prostaglandin E2, phosphonic acid, lysine, threonine, and phenylalanine, exhibit associations with autism. Additionally, the involvement of the phosphatidylinositol and inositol phosphate pathways suggests their potential role in the pathophysiology of autism.
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Affiliation(s)
- Xian Liu
- Department of Children’s and Adolescent Health, College of Public Health, Harbin Medical University, Harbin, China
- Division of Birth Cohort Study, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Xin Sun
- Clinical Research and Innovation Center, Xinhua Hospital Affiliated with Shanghai Jiao Tong University, Shanghai, China
| | - Cheng Guo
- The Assessment and Intervention Center for Autistic Children, Guangzhou Women and Children’s Medical Center, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Zhi-Fang Huang
- The Assessment and Intervention Center for Autistic Children, Guangzhou Women and Children’s Medical Center, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Yi-Ru Chen
- The Assessment and Intervention Center for Autistic Children, Guangzhou Women and Children’s Medical Center, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Fang-Mei Feng
- The Assessment and Intervention Center for Autistic Children, Guangzhou Women and Children’s Medical Center, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Li-Jie Wu
- Department of Children’s and Adolescent Health, College of Public Health, Harbin Medical University, Harbin, China
| | - Wen-Xiong Chen
- The Assessment and Intervention Center for Autistic Children, Guangzhou Women and Children’s Medical Center, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
- Department of Neurology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
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2
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van Wijngaarden V, de Wilde H, Mink van der Molen D, Petter J, Stegeman I, Gerrits E, Smit AL, van den Boogaard MJ. Genetic outcomes in children with developmental language disorder: a systematic review. Front Pediatr 2024; 12:1315229. [PMID: 38298611 PMCID: PMC10828955 DOI: 10.3389/fped.2024.1315229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/02/2024] [Indexed: 02/02/2024] Open
Abstract
Introduction Developmental language disorder (DLD) is a common childhood condition negatively influencing communication and psychosocial development. An increasing number of pathogenic variants or chromosomal anomalies possibly related to DLD have been identified. To provide a base for accurate clinical genetic diagnostic work-up for DLD patients, understanding the specific genetic background is crucial. This study aims to give a systematic literature overview of pathogenic variants or chromosomal anomalies causative for DLD in children. Methods We conducted a systematic search in PubMed and Embase on available literature related to the genetic background of diagnosed DLD in children. Included papers were critically appraised before data extraction. An additional search in OMIM was performed to see if the described DLD genes are associated with a broader clinical spectrum. Results The search resulted in 15,842 papers. After assessing eligibility, 47 studies remained, of which 25 studies related to sex chromosome aneuploidies and 15 papers concerned other chromosomal anomalies (SCAs) and/or Copy Number Variants (CNVs), including del15q13.1-13.3 and del16p11.2. The remaining 7 studies displayed a variety of gene variants. 45 (candidate) genes related to language development, including FOXP2, GRIN2A, ERC1, and ATP2C2. After an additional search in the OMIM database, 22 of these genes were associated with a genetic disorder with a broader clinical spectrum, including intellectual disability, epilepsy, and/or autism. Conclusion Our study illustrates that DLD can be related to SCAs and specific CNV's. The reported (candidate) genes (n = 45) in the latter category reflect the genetic heterogeneity and support DLD without any comorbidities and syndromic language disorder have an overlapping genetic etiology.
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Affiliation(s)
| | - Hester de Wilde
- Department of Pediatric Otorhinolaryngology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, Netherlands
| | | | - Jildo Petter
- Faculty of Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Inge Stegeman
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- Brain Center, University Medical Center Utrecht, Utrecht, Netherlands
| | - Ellen Gerrits
- Research Group Speech and Language Therapy, HU University of Applied Sciences Utrecht, Utrecht, Netherlands
- Department of Languages, Literature and Communication, Faculty of Humanities, Utrecht University, Utrecht, Netherlands
| | - Adriana L. Smit
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht, Netherlands
- Research Group Speech and Language Therapy, HU University of Applied Sciences Utrecht, Utrecht, Netherlands
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3
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Mota A, Waxman HK, Hong R, Lagani GD, Niu SY, Bertherat FL, Wolfe L, Malicdan CM, Markello TC, Adams DR, Gahl WA, Cheng CS, Beffert U, Ho A. FOXR1 regulates stress response pathways and is necessary for proper brain development. PLoS Genet 2021; 17:e1009854. [PMID: 34723967 PMCID: PMC8559929 DOI: 10.1371/journal.pgen.1009854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 10/01/2021] [Indexed: 11/20/2022] Open
Abstract
The forkhead box (Fox) family of transcription factors are highly conserved and play essential roles in a wide range of cellular and developmental processes. We report an individual with severe neurological symptoms including postnatal microcephaly, progressive brain atrophy and global developmental delay associated with a de novo missense variant (M280L) in the FOXR1 gene. At the protein level, M280L impaired FOXR1 expression and induced a nuclear aggregate phenotype due to protein misfolding and proteolysis. RNAseq and pathway analysis showed that FOXR1 acts as a transcriptional activator and repressor with central roles in heat shock response, chaperone cofactor-dependent protein refolding and cellular response to stress pathways. Indeed, FOXR1 expression is increased in response to cellular stress, a process in which it directly controls HSPA6, HSPA1A and DHRS2 transcripts. The M280L mutant compromises FOXR1's ability to respond to stress, in part due to impaired regulation of downstream target genes that are involved in the stress response pathway. Quantitative PCR of mouse embryo tissues show Foxr1 expression in the embryonic brain. Using CRISPR/Cas9 gene editing, we found that deletion of mouse Foxr1 leads to a severe survival deficit while surviving newborn Foxr1 knockout mice have reduced body weight. Further examination of newborn Foxr1 knockout brains revealed a decrease in cortical thickness and enlarged ventricles compared to littermate wild-type mice, suggesting that loss of Foxr1 leads to atypical brain development. Combined, these results suggest FOXR1 plays a role in cellular stress response pathways and is necessary for normal brain development.
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Affiliation(s)
- Andressa Mota
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Hannah K. Waxman
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Rui Hong
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
| | - Gavin D. Lagani
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Sheng-Yong Niu
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Féodora L. Bertherat
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Lynne Wolfe
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, and National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Christine May Malicdan
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, and National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thomas C. Markello
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, and National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David R. Adams
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, and National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - William A. Gahl
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, and National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Christine S. Cheng
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
| | - Uwe Beffert
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Angela Ho
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
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4
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3D Genome of macaque fetal brain reveals evolutionary innovations during primate corticogenesis. Cell 2021; 184:723-740.e21. [PMID: 33508230 DOI: 10.1016/j.cell.2021.01.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 11/09/2020] [Accepted: 12/31/2020] [Indexed: 02/06/2023]
Abstract
Elucidating the regulatory mechanisms of human brain evolution is essential to understanding human cognition and mental disorders. We generated multi-omics profiles and constructed a high-resolution map of 3D genome architecture of rhesus macaque during corticogenesis. By comparing the 3D genomes of human, macaque, and mouse brains, we identified many human-specific chromatin structure changes, including 499 topologically associating domains (TADs) and 1,266 chromatin loops. The human-specific loops are significantly enriched in enhancer-enhancer interactions, and the regulated genes show human-specific expression changes in the subplate, a transient zone of the developing brain critical for neural circuit formation and plasticity. Notably, many human-specific sequence changes are located in the human-specific TAD boundaries and loop anchors, which may generate new transcription factor binding sites and chromatin structures in human. Collectively, the presented data highlight the value of comparative 3D genome analyses in dissecting the regulatory mechanisms of brain development and evolution.
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5
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Anholt RRH. Evolution of Epistatic Networks and the Genetic Basis of Innate Behaviors. Trends Genet 2019; 36:24-29. [PMID: 31706688 DOI: 10.1016/j.tig.2019.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/20/2019] [Accepted: 10/15/2019] [Indexed: 01/07/2023]
Abstract
Instinctive behaviors are genetically programmed behaviors that occur independent of experience. How genetic programs that give rise to the manifestation of such behaviors evolve remains an unresolved question. I propose that evolution of species-specific innate behaviors is accomplished through progressive modifications of pre-existing genetic networks composed of allelic variants. I hypothesize that changes in frequencies of one or more constituent allelic variants within the network leads to changes in gene network connectivity and the emergence of a reorganized network that can support the emergence of a novel behavioral phenotype and becomes stabilized when key allelic variants are driven to fixation.
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Affiliation(s)
- Robert R H Anholt
- Department of Genetics and Biochemistry and Center for Human Genetics, Clemson University, Greenwood, SC, 29646, USA.
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6
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Bademci G, Abad C, Incesulu A, Elian F, Reyahi A, Diaz-Horta O, Cengiz FB, Sineni CJ, Seyhan S, Atli EI, Basmak H, Demir S, Nik AM, Footz T, Guo S, Duman D, Fitoz S, Gurkan H, Blanton SH, Walter MA, Carlsson P, Walz K, Tekin M. FOXF2 is required for cochlear development in humans and mice. Hum Mol Genet 2019; 28:1286-1297. [PMID: 30561639 DOI: 10.1093/hmg/ddy431] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 11/14/2022] Open
Abstract
Molecular mechanisms governing the development of the human cochlea remain largely unknown. Through genome sequencing, we identified a homozygous FOXF2 variant c.325A>T (p.I109F) in a child with profound sensorineural hearing loss (SNHL) associated with incomplete partition type I anomaly of the cochlea. This variant is not found in public databases or in over 1000 ethnicity-matched control individuals. I109 is a highly conserved residue in the forkhead box (Fox) domain of FOXF2, a member of the Fox protein family of transcription factors that regulate the expression of genes involved in embryogenic development as well as adult life. Our in vitro studies show that the half-life of mutant FOXF2 is reduced compared to that of wild type. Foxf2 is expressed in the cochlea of developing and adult mice. The mouse knockout of Foxf2 shows shortened and malformed cochleae, in addition to altered shape of hair cells with innervation and planar cell polarity defects. Expressions of Eya1 and Pax3, genes essential for cochlear development, are reduced in the cochleae of Foxf2 knockout mice. We conclude that FOXF2 plays a major role in cochlear development and its dysfunction leads to SNHL and developmental anomalies of the cochlea in humans and mice.
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Affiliation(s)
- Guney Bademci
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Clemer Abad
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Armagan Incesulu
- Department of Otolaryngology-Head and Neck Surgery, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Fahed Elian
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Azadeh Reyahi
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Oscar Diaz-Horta
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Filiz B Cengiz
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Claire J Sineni
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Serhat Seyhan
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Medical Genetics, Bakirkoy Dr Sadi Konuk Research and Training Hospital, Istanbul, Turkey
| | - Emine Ikbal Atli
- Department of Medical Genetics, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Hikmet Basmak
- Department of Ophthalmology, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Selma Demir
- Department of Medical Genetics, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Ali Moussavi Nik
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Tim Footz
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Shengru Guo
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Duygu Duman
- Division of Pediatric Genetics, Ankara University School of Medicine, Ankara, Turkey
| | - Suat Fitoz
- Department of Radiology, Ankara University School of Medicine, Ankara, Turkey
| | - Hakan Gurkan
- Department of Medical Genetics, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Susan H Blanton
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA.,Dr John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Michael A Walter
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Peter Carlsson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Katherina Walz
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA.,Dr John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Mustafa Tekin
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA.,Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA.,Dr John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
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7
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Hickey SL, Berto S, Konopka G. Chromatin Decondensation by FOXP2 Promotes Human Neuron Maturation and Expression of Neurodevelopmental Disease Genes. Cell Rep 2019; 27:1699-1711.e9. [PMID: 31067457 PMCID: PMC6794152 DOI: 10.1016/j.celrep.2019.04.044] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 03/08/2019] [Accepted: 04/08/2019] [Indexed: 01/06/2023] Open
Abstract
Forkhead box P2 (FOXP2) is a transcription factor expressed in the human brain that peaks during fetal development, and disruption in its ability to regulate downstream target genes leads to vulnerability to neurodevelopmental disorders. However, the mechanisms by which FOXP2 exerts regulatory control over targets during neuronal maturation have not been fully elucidated. Here, we use genome-wide chromatin accessibility assays and transcriptome-wide expression analyses in differentiating human neurons to show that FOXP2 represses proliferation-promoting genes in a DNA-binding-dependent manner. In contrast, FOXP2 and its cofactors, NFIA and NFIB, activate neuronal maturation genes in a manner that does not require FOXP2 to interact with DNA directly. Moreover, comparisons with expression data from the developing human brain suggest that FOXP2 and NFIA- or NFIB-dependent chromatin alterations drive maturation of excitatory cortical neurons. Thus, FOXP2 and its NFI cofactors may be specifically important for the development of cortical circuits underlying neurodevelopmental disorders.
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Affiliation(s)
- Stephanie L Hickey
- Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Stefano Berto
- Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Genevieve Konopka
- Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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8
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Cheung LYM, George AS, McGee SR, Daly AZ, Brinkmeier ML, Ellsworth BS, Camper SA. Single-Cell RNA Sequencing Reveals Novel Markers of Male Pituitary Stem Cells and Hormone-Producing Cell Types. Endocrinology 2018; 159:3910-3924. [PMID: 30335147 PMCID: PMC6240904 DOI: 10.1210/en.2018-00750] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/09/2018] [Indexed: 12/22/2022]
Abstract
Transcription factors and signaling pathways that regulate stem cells and specialized hormone-producing cells in the pituitary gland have been the subject of intense study and have yielded a mechanistic understanding of pituitary organogenesis and disease. However, the regulation of stem cell proliferation and differentiation, the heterogeneity among specialized hormone-producing cells, and the role of nonendocrine cells in the gland remain important, unanswered questions. Recent advances in single-cell RNA sequencing (scRNAseq) technologies provide new avenues to address these questions. We performed scRNAseq on ∼13,663 cells pooled from six whole pituitary glands of 7-week-old C57BL/6 male mice. We identified pituitary endocrine and stem cells in silico, as well as other support cell types such as endothelia, connective tissue, and red and white blood cells. Differential gene expression analyses identify known and novel markers of pituitary endocrine and stem cell populations. We demonstrate the value of scRNAseq by in vivo validation of a novel gonadotrope-enriched marker, Foxp2. We present novel scRNAseq data of in vivo pituitary tissue, including data from agnostic clustering algorithms that suggest the presence of a somatotrope subpopulation enriched in sterol/cholesterol synthesis genes. Additionally, we show that incomplete transcriptome annotation can cause false negatives on some scRNAseq platforms that only generate 3' transcript end sequences, and we use in vivo data to recover reads of the pituitary transcription factor Prop1. Ultimately, scRNAseq technologies represent a significant opportunity to address long-standing questions regarding the development and function of the different populations of the pituitary gland throughout life.
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Affiliation(s)
- Leonard Y M Cheung
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan
| | - Akima S George
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan
| | - Stacey R McGee
- Department of Physiology, Southern Illinois University, Carbondale, Illinois
| | - Alexandre Z Daly
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan
| | | | - Buffy S Ellsworth
- Department of Physiology, Southern Illinois University, Carbondale, Illinois
| | - Sally A Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan
- Correspondence: Sally A. Camper, PhD, Department of Human Genetics, University of Michigan, 5805 Medical Science Building II, 1241 East Catherine Street, Ann Arbor, Michigan 48109. E-mail:
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9
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Atkinson EG, Audesse AJ, Palacios JA, Bobo DM, Webb AE, Ramachandran S, Henn BM. No Evidence for Recent Selection at FOXP2 among Diverse Human Populations. Cell 2018; 174:1424-1435.e15. [PMID: 30078708 DOI: 10.1016/j.cell.2018.06.048] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 06/15/2018] [Accepted: 06/26/2018] [Indexed: 12/18/2022]
Abstract
FOXP2, initially identified for its role in human speech, contains two nonsynonymous substitutions derived in the human lineage. Evidence for a recent selective sweep in Homo sapiens, however, is at odds with the presence of these substitutions in archaic hominins. Here, we comprehensively reanalyze FOXP2 in hundreds of globally distributed genomes to test for recent selection. We do not find evidence of recent positive or balancing selection at FOXP2. Instead, the original signal appears to have been due to sample composition. Our tests do identify an intronic region that is enriched for highly conserved sites that are polymorphic among humans, compatible with a loss of function in humans. This region is lowly expressed in relevant tissue types that were tested via RNA-seq in human prefrontal cortex and RT-PCR in immortalized human brain cells. Our results represent a substantial revision to the adaptive history of FOXP2, a gene regarded as vital to human evolution.
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Affiliation(s)
| | - Amanda Jane Audesse
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912, USA; Neuroscience Graduate Program, Brown University, Providence, RI 02912, USA
| | - Julia Adela Palacios
- Department of Ecology and Evolutionary Biology and Center for Computational Molecular Biology, Brown University, Providence, RI 02912, USA; Department of Statistics and Department of Biomedical Data Science, Stanford University, Stanford, CA 94305, USA
| | - Dean Michael Bobo
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY, USA
| | - Ashley Elizabeth Webb
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912, USA; Carney Institute for Brain Science, Brown University, Providence, RI 02912, USA
| | - Sohini Ramachandran
- Department of Ecology and Evolutionary Biology and Center for Computational Molecular Biology, Brown University, Providence, RI 02912, USA
| | - Brenna Mariah Henn
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY, USA; Department of Anthropology and the Genome Center, University of California, Davis, Davis, CA 95616, USA.
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10
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Iuzzini-Seigel J, Murray E. Speech Assessment in Children With Childhood Apraxia of Speech. ACTA ACUST UNITED AC 2017. [DOI: 10.1044/persp2.sig2.47] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This article uses the International Classification of Functioning (ICF) framework to outline the assessment needs of children with apraxia of speech. Specifically, the level of breakdown for children with apraxia of speech—that of motor planning and programming at the level of body functions—is delineated using operationally defined criteria for greater diagnostic transparency.
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Affiliation(s)
- Jenya Iuzzini-Seigel
- Communication, Movement and Learning Lab, Department of Speech Pathology and Audiology, Marquette University
Milwaukee, WI
| | - Elizabeth Murray
- Faculty of Health Sciences, The University of Sydney
Lidcombe NSW, Australia
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11
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Meredith LJ, Wang CM, Nascimento L, Liu R, Wang L, Yang WH. The Key Regulator for Language and Speech Development, FOXP2, is a Novel Substrate for SUMOylation. J Cell Biochem 2016. [PMID: 26212494 DOI: 10.1002/jcb.25288] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Transcription factor forkhead box protein P2 (FOXP2) plays an essential role in the development of language and speech. However, the transcriptional activity of FOXP2 regulated by the post-translational modifications remains unknown. Here, we demonstrated that FOXP2 is clearly defined as a SUMO target protein at the cellular levels as FOXP2 is covalently modified by both SUMO1 and SUMO3. Furthermore, SUMOylation of FOXP2 was significantly decreased by SENP2 (a specific SUMOylation protease). We further showed that FOXP2 is selectively SUMOylated in vivo on a phylogenetically conserved lysine 674 but the SUMOylation does not alter subcellular localization and stability of FOXP2. Interestingly, we observed that human etiological FOXP2 R553H mutation robustly reduces its SUMOylation potential as compared to wild-type FOXP2. In addition, the acidic residues downstream the core SUMO motif on FOXP2 are required for its full SUMOylation capacity. Finally, our functional analysis using reporter gene assays showed that SUMOylation may modulate transcriptional activity of FOXP2 in regulating downstream target genes (DISC1, SRPX2, and MiR200c). Altogether, we provide the first evidence that FOXP2 is a substrate for SUMOylation and SUMOylation of FOXP2 plays a functional role in regulating its transcriptional activity.
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Affiliation(s)
- Leslie J Meredith
- Department of Biomedical Sciences, Mercer University School of Medicine, Savannah, Georgia 30404
| | - Chiung-Min Wang
- Department of Biomedical Sciences, Mercer University School of Medicine, Savannah, Georgia 30404
| | - Leticia Nascimento
- Department of Biomedical Sciences, Mercer University School of Medicine, Savannah, Georgia 30404
| | - Runhua Liu
- Department of Genetics and Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Lizhong Wang
- Department of Genetics and Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Wei-Hsiung Yang
- Department of Biomedical Sciences, Mercer University School of Medicine, Savannah, Georgia 30404
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12
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Zimmerman E, Maron JL. FOXP2 gene deletion and infant feeding difficulties: a case report. Cold Spring Harb Mol Case Stud 2016; 2:a000547. [PMID: 27148578 PMCID: PMC4849845 DOI: 10.1101/mcs.a000547] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Forkhead box protein P2 (FOXP2) is a well-studied gene known to play an essential role in normal speech development. Deletions in the gene have been shown to result in developmental speech disorders and regulatory disruption of downstream gene targets associated with common forms of language impairments. Despite similarities in motor planning and execution between speech development and oral feeding competence, there have been no reports to date linking deletions within the FOXP2 gene to oral feeding impairments in the newborn. The patient was a nondysmorphic, appropriately and symmetrically grown male infant born at 35-wk gestational age. He had a prolonged neonatal intensive care unit stay because of persistent oral feeding incoordination requiring gastrostomy tube placement. Cardiac and neurological imagings were within normal limits. A microarray analysis found an ∼9-kb loss within chromosome band 7q3.1 that contains exon 2 of FOXP2, demonstrating a single copy of this region instead of the normal two copies per diploid gene. This case study expands our current understanding of the role FOXP2 exerts on motor planning and coordination necessary for both oral feeding success and speech–language development. This case report has important consequences for future diagnosis and treatment for infants with FOXP2 deletions, mutations, and varying levels of gene expression.
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Affiliation(s)
- Emily Zimmerman
- Northeastern University, Department of Communication Sciences & Disorders, Boston, Massachusetts 02115, USA
| | - Jill L Maron
- Mother Infant Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, USA
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13
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Zimmerman E, Maki M, Maron J. Salivary FOXP2 expression and oral feeding success in premature infants. Cold Spring Harb Mol Case Stud 2016; 2:a000554. [PMID: 27148579 PMCID: PMC4849846 DOI: 10.1101/mcs.a000554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The objective of the study is to determine whether salivary FOXP2 gene expression levels at the initiation of oral feeding attempts are predictive of oral feeding success in the premature newborn. In this prospective study, saliva samples from 21 premature infants (13 males; birth gestational age [GA]: 30–34 wk) were collected around the initiation of oral feeding trials. Total RNA was extracted and underwent reverse transcription-quantitative polymerase chain reaction amplification for FOXP2. Oral feeding success was denoted by the days required to attain full oral feeds. A linear regression model, controlling for sex, birth GA, and weight at salivary collection, revealed that FOXP2 expression was significantly associated with oral feeding success (P = 0.002). The higher the expression level of FOXP2, the shorter the duration to feed. Salivary FOXP2 expression levels are significantly associated with oral feeding success in the preterm infant. FOXP2 may serve as a novel and informative biomarker to noninvasively assess infant feeding skills to reduce morbidities and length of stay.
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Affiliation(s)
- Emily Zimmerman
- Department of Communication Sciences and Disorders, Northeastern University, Boston, Massachusetts 02115, USA
| | - Monika Maki
- Department of Communication Sciences and Disorders, Northeastern University, Boston, Massachusetts 02115, USA
| | - Jill Maron
- Mother Infant Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, USA
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14
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Evans PD, Mueller KL, Gamazon ER, Cox NJ, Tomblin JB. A genome-wide sib-pair scan for quantitative language traits reveals linkage to chromosomes 10 and 13. GENES BRAIN AND BEHAVIOR 2016; 14:387-97. [PMID: 25997078 DOI: 10.1111/gbb.12223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 02/03/2023]
Abstract
Although there is considerable evidence that individual differences in language development are highly heritable, there have been few genome-wide scans to locate genes associated with the trait. Previous analyses of language impairment have yielded replicable evidence for linkage to regions on chromosomes 16q, 19q, 13q (within lab) and at 13q (between labs). Here we report the first linkage study to screen the continuum of language ability, from normal to disordered, as found in the general population. 383 children from 147 sib-ships (214 sib-pairs) were genotyped on the Illumina(®) Linkage IVb Marker Panel using three composite language-related phenotypes and a measure of phonological memory (PM). Two regions (10q23.33; 13q33.3) yielded genome-wide significant peaks for linkage with PM. A peak suggestive of linkage was also found at 17q12 for the overall language composite. This study presents two novel genetic loci for the study of language development and disorders, but fails to replicate findings by previous groups. Possible reasons for this are discussed.
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Affiliation(s)
- P D Evans
- Department of Medicine, The University of Chicago, IL, USA
| | - K L Mueller
- Murdoch Childrens Research Institute, Melbourne, Australia.,Department of Communication Sciences and Disorders, The University of Iowa, IA, USA
| | - E R Gamazon
- Department of Medicine, The University of Chicago, IL, USA.,Present address: Division of Genetic Medicine, Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - N J Cox
- Department of Medicine, The University of Chicago, IL, USA.,Department of Communication Sciences and Disorders, The University of Iowa, IA, USA.,Present address: Division of Genetic Medicine, Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - J B Tomblin
- Department of Communication Sciences and Disorders, The University of Iowa, IA, USA
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15
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Gaub S, Fisher SE, Ehret G. Ultrasonic vocalizations of adult male Foxp2-mutant mice: behavioral contexts of arousal and emotion. GENES BRAIN AND BEHAVIOR 2016; 15:243-59. [PMID: 26566793 DOI: 10.1111/gbb.12274] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 11/09/2015] [Accepted: 11/10/2015] [Indexed: 01/27/2023]
Abstract
Adult mouse ultrasonic vocalizations (USVs) occur in multiple behavioral and stimulus contexts associated with various levels of arousal, emotion and social interaction. Here, in three experiments of increasing stimulus intensity (water; female urine; male interacting with adult female), we tested the hypothesis that USVs of adult males express the strength of arousal and emotion via different USV parameters (18 parameters analyzed). Furthermore, we analyzed two mouse lines with heterozygous Foxp2 mutations (R552H missense, S321X nonsense), known to produce severe speech and language disorders in humans. These experiments allowed us to test whether intact Foxp2 function is necessary for developing full adult USV repertoires, and whether mutations of this gene influence instinctive vocal expressions based on arousal and emotion. The results suggest that USV calling rate characterizes the arousal level, while sound pressure and spectrotemporal call complexity (overtones/harmonics, type of frequency jumps) may provide indices of levels of positive emotion. The presence of Foxp2 mutations did not qualitatively affect the USVs; all USV types that were found in wild-type animals also occurred in heterozygous mutants. However, mice with Foxp2 mutations displayed quantitative differences in USVs as compared to wild-types, and these changes were context dependent. Compared to wild-type animals, heterozygous mutants emitted mainly longer and louder USVs at higher minimum frequencies with a higher occurrence rate of overtones/harmonics and complex frequency jump types. We discuss possible hypotheses about Foxp2 influence on emotional vocal expressions, which can be investigated in future experiments using selective knockdown of Foxp2 in specific brain circuits.
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Affiliation(s)
- S Gaub
- Institute of Neurobiology, University of Ulm, Germany
| | - S E Fisher
- Department of Language and Genetics, Max Planck Institute for Psycholinguistics.,Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - G Ehret
- Institute of Neurobiology, University of Ulm, Germany
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16
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Abstract
Language is a defining characteristic of the human species, but its foundations remain mysterious. Heritable disorders offer a gateway into biological underpinnings, as illustrated by the discovery that FOXP2 disruptions cause a rare form of speech and language impairment. The genetic architecture underlying language-related disorders is complex, and although some progress has been made, it has proved challenging to pinpoint additional relevant genes with confidence. Next-generation sequencing and genome-wide association studies are revolutionizing understanding of the genetic bases of other neurodevelopmental disorders, like autism and schizophrenia, and providing fundamental insights into the molecular networks crucial for typical brain development. We discuss how a similar genomic perspective, brought to the investigation of language-related phenotypes, promises to yield equally informative discoveries. Moreover, we outline how follow-up studies of genetic findings using cellular systems and animal models can help to elucidate the biological mechanisms involved in the development of brain circuits supporting language.
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Affiliation(s)
- Sarah A Graham
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, 6525 XD Nijmegen, The Netherlands;
| | - Simon E Fisher
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, 6525 XD Nijmegen, The Netherlands; .,Donders Institute for Brain, Cognition and Behavior, Radboud University, 6525 EN Nijmegen, The Netherlands;
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17
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Rogers RL. Chromosomal Rearrangements as Barriers to Genetic Homogenization between Archaic and Modern Humans. Mol Biol Evol 2015; 32:3064-78. [PMID: 26399483 DOI: 10.1093/molbev/msv204] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chromosomal rearrangements, which shuffle DNA throughout the genome, are an important source of divergence across taxa. Using a paired-end read approach with Illumina sequence data for archaic humans, I identify changes in genome structure that occurred recently in human evolution. Hundreds of rearrangements indicate genomic trafficking between the sex chromosomes and autosomes, raising the possibility of sex-specific changes. Additionally, genes adjacent to genome structure changes in Neanderthals are associated with testis-specific expression, consistent with evolutionary theory that new genes commonly form with expression in the testes. I identify one case of new-gene creation through transposition from the Y chromosome to chromosome 10 that combines the 5'-end of the testis-specific gene Fank1 with previously untranscribed sequence. This new transcript experienced copy number expansion in archaic genomes, indicating rapid genomic change. Among rearrangements identified in Neanderthals, 13% are transposition of selfish genetic elements, whereas 32% appear to be ectopic exchange between repeats. In Denisovan, the pattern is similar but numbers are significantly higher with 18% of rearrangements reflecting transposition and 40% ectopic exchange between distantly related repeats. There is an excess of divergent rearrangements relative to polymorphism in Denisovan, which might result from nonuniform rates of mutation, possibly reflecting a burst of transposable element activity in the lineage that led to Denisovan. Finally, loci containing genome structure changes show diminished rates of introgression from Neanderthals into modern humans, consistent with the hypothesis that rearrangements serve as barriers to gene flow during hybridization. Together, these results suggest that this previously unidentified source of genomic variation has important biological consequences in human evolution.
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Affiliation(s)
- Rebekah L Rogers
- Department of Integrative Biology, University of California, Berkeley
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18
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Kang C. Genetic studies on speech and language disorders. J Biomed Res 2015. [DOI: 10.12729/jbr.2015.16.3.077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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19
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Abstract
Specific language impairment (SLI) is a multifactorial neurodevelopmental disorder which occurs unexpectedly and without an obvious cause. Over a decade of research suggests that SLI is highly heritable. Several genes and loci have already been implicated in SLI through linkage and targeted association methods. Recently, genome-wide association studies (GWAS) of SLI and language traits in the general population have been reported and, consequently, new candidate genes have been identified. This review aims to summarise the literature concerning genome-wide studies of SLI. In addition, this review highlights the methodologies that have been used to research the genetics of SLI to date, and also considers the current, and future, contributions that GWAS can offer.
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Affiliation(s)
- Rose H Reader
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Laura E Covill
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Ron Nudel
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK
| | - Dianne F Newbury
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN UK ; St John's College, University of Oxford, Oxford, OX1 3JP UK
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20
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Utine GE, Haliloğlu G, Volkan-Salancı B, Çetinkaya A, Kiper PÖ, Alanay Y, Aktaş D, Anlar B, Topçu M, Boduroğlu K, Alikaşifoğlu M. Etiological yield of SNP microarrays in idiopathic intellectual disability. Eur J Paediatr Neurol 2014; 18:327-37. [PMID: 24508361 DOI: 10.1016/j.ejpn.2014.01.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 12/23/2013] [Accepted: 01/10/2014] [Indexed: 01/30/2023]
Abstract
Intellectual disability (ID) has a prevalence of 3% and is classified according to its severity. An underlying etiology cannot be determined in 75-80% in mild ID, and in 20-50% of severe ID. After it has been shown that copy number variations involving short DNA segments may cause ID, genome-wide SNP microarrays are being used as a tool for detecting submicroscopic copy number changes and uniparental disomy. This study was performed to investigate the presence of copy number changes in patients with ID of unidentified etiology. Affymetrix(®) 6.0 SNP microarray platform was used for analysis of 100 patients and their healthy parents, and data were evaluated using various databases and literature. Etiological diagnoses were made in 12 patients (12%). Homozygous deletion in NRXN1 gene and duplication in IL1RAPL1 gene were detected for the first time. Two separate patients had deletions in FOXP2 and UBE2A genes, respectively, for which only few patients have recently been reported. Interstitial and subtelomeric copy number changes were described in 6 patients, in whom routine cytogenetic tools revealed normal results. In one patient uniparental disomy type of Angelman syndrome was diagnosed. SNP microarrays constitute a screening test able to detect very small genomic changes, with a high etiological yield even in patients already evaluated using traditional cytogenetic tools, offer analysis for uniparental disomy and homozygosity, and thereby are helpful in finding novel disease-causing genes: for these reasons they should be considered as a first-tier genetic screening test in the evaluation of patients with ID and autism.
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Affiliation(s)
- G Eda Utine
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey.
| | - Göknur Haliloğlu
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Neurology, Ankara, Turkey
| | - Bilge Volkan-Salancı
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey
| | - Arda Çetinkaya
- Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey; Hacettepe University, Department of Medical Genetics, Ankara, Turkey
| | - Pelin Ö Kiper
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey
| | - Yasemin Alanay
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey
| | - Dilek Aktaş
- Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey; Hacettepe University, Department of Medical Genetics, Ankara, Turkey
| | - Banu Anlar
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Neurology, Ankara, Turkey
| | - Meral Topçu
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Neurology, Ankara, Turkey
| | - Koray Boduroğlu
- Hacettepe University, Department of Pediatrics, Ankara, Turkey; Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey
| | - Mehmet Alikaşifoğlu
- Hacettepe University, Department of Pediatric Genetics, Ankara, Turkey; Hacettepe University, Department of Medical Genetics, Ankara, Turkey
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21
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Bertelsen B, Debes NM, Hjermind LE, Skov L, Brøndum-Nielsen K, Tümer Z. Chromosomal rearrangements in Tourette syndrome: implications for identification of candidate susceptibility genes and review of the literature. Neurogenetics 2013; 14:197-203. [DOI: 10.1007/s10048-013-0372-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 08/14/2013] [Indexed: 12/25/2022]
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22
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Nudel R, Newbury DF. FOXP2. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2013; 4:547-560. [PMID: 24765219 PMCID: PMC3992897 DOI: 10.1002/wcs.1247] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 06/04/2013] [Accepted: 07/06/2013] [Indexed: 11/30/2022]
Abstract
The forkhead box P2 gene, designated FOXP2, is the first gene implicated in a speech and language disorder. Since its discovery, many studies have been carried out in an attempt to explain the mechanism by which it influences these characteristically human traits. This review presents the story of the discovery of the FOXP2 gene, including early studies of the phenotypic implications of a disruption in the gene. We then discuss recent investigations into the molecular function of the FOXP2 gene, including functional and gene expression studies. We conclude this review by presenting the fascinating results of recent studies of the FOXP2 ortholog in other species that are capable of vocal communication. WIREs Cogn Sci 2013, 4:547–560. doi: 10.1002/wcs.1247
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Affiliation(s)
- Ron Nudel
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Dianne F Newbury
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
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23
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Genetic insights into the functional elements of language. Hum Genet 2013; 132:959-86. [PMID: 23749164 DOI: 10.1007/s00439-013-1317-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 05/22/2013] [Indexed: 12/11/2022]
Abstract
Language disorders cover a wide range of conditions with heterologous and overlapping phenotypes and complex etiologies harboring both genetic and environmental influences. Genetic approaches including the identification of genes linked to speech and language phenotypes and the characterization of normal and aberrant functions of these genes have, in recent years, unraveled complex details of molecular and cognitive mechanisms and provided valuable insight into the biological foundations of language. Consistent with this approach, we have reviewed the functional aspects of allelic variants of genes which are currently known to be either causally associated with disorders of speech and language or impact upon the spectrum of normal language ability. We have also reviewed candidate genes associated with heritable speech and language disorders. In addition, we have evaluated language phenotypes and associated genetic components in developmental syndromes that, together with a spectrum of altered language abilities, manifest various phenotypes and offer details of multifactorial determinants of language function. Data from this review have revealed a predominance of regulatory networks involved in the control of differentiation and functioning of neurons, neuronal tracks and connections among brain structures associated with both cognitive and language faculties. Our findings, furthermore, have highlighted several multifactorial determinants in overlapping speech and language phenotypes. Collectively this analysis has revealed an interconnected developmental network and a close association of the language faculty with cognitive functions, a finding that has the potential to provide insight into linguistic hypotheses defining in particular, the contribution of genetic elements to and the modular nature of the language faculty.
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24
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Rice ML. Language growth and genetics of specific language impairment. INTERNATIONAL JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2013; 15:223-33. [PMID: 23614332 PMCID: PMC3684183 DOI: 10.3109/17549507.2013.783113] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Behavioural studies of children with specific language impairment (SLI) have reported long-term growth outcomes across different dimensions of language. Genetic studies of children with SLI have identified candidate genes and putative associations of gene variants with SLI. The aims of this review are to summarize these two lines of investigation and to highlight the possible role of underlying growth timing mechanisms that influence the trajectory of language outcomes throughout childhood and into adolescence. Behavioural growth trajectories demonstrate that children with SLI have notable strengths in language acquisition, as well as limitations, across different dimensions of language. Language onset appears delayed, although the rate and pattern of change over time is similar to unaffected children. Growth rate decelerates early in adolescence for some dimensions of language. Genetic investigations reveal candidate genes that are known to influence neuronal development, and reveal possible gene interactions along a causal pathway. Epigenetic studies reveal other genetic influences implicated in the cognitive decline associated with ageing. This review highlights possible parallels between underlying genetic mechanisms and characteristics of linguistic growth trajectories. The conclusion is that new developmental perspectives are needed to inform language intervention in ways that align nurture with nature.
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Affiliation(s)
- Mabel L Rice
- Child Language Doctoral Program, University of Kansas, Lawrence, KS 66045, USA.
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25
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Abstract
Next-generation sequencing is set to transform the discovery of genes underlying neurodevelopmental disorders, and so offer important insights into the biological bases of spoken language. Success will depend on functional assessments in neuronal cell lines, animal models and humans themselves.
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Affiliation(s)
- Pelagia Deriziotis
- Max Planck Institute for Psycholinguistics, 6525 XD Nijmegen, The Netherlands
| | - Simon E Fisher
- Max Planck Institute for Psycholinguistics, 6525 XD Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 EN Nijmegen, The Netherlands
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26
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O’Roak BJ, Vives L, Fu W, Egertson JD, Stanaway IB, Phelps IG, Carvill G, Kumar A, Lee C, Ankenman K, Munson J, Hiatt JB, Turner EH, Levy R, O’Day DR, Krumm N, Coe BP, Martin BK, Borenstein E, Nickerson DA, Mefford HC, Doherty D, Akey JM, Bernier R, Eichler EE, Shendure J. Multiplex targeted sequencing identifies recurrently mutated genes in autism spectrum disorders. Science 2012; 338:1619-22. [PMID: 23160955 PMCID: PMC3528801 DOI: 10.1126/science.1227764] [Citation(s) in RCA: 935] [Impact Index Per Article: 77.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Exome sequencing studies of autism spectrum disorders (ASDs) have identified many de novo mutations but few recurrently disrupted genes. We therefore developed a modified molecular inversion probe method enabling ultra-low-cost candidate gene resequencing in very large cohorts. To demonstrate the power of this approach, we captured and sequenced 44 candidate genes in 2446 ASD probands. We discovered 27 de novo events in 16 genes, 59% of which are predicted to truncate proteins or disrupt splicing. We estimate that recurrent disruptive mutations in six genes-CHD8, DYRK1A, GRIN2B, TBR1, PTEN, and TBL1XR1-may contribute to 1% of sporadic ASDs. Our data support associations between specific genes and reciprocal subphenotypes (CHD8-macrocephaly and DYRK1A-microcephaly) and replicate the importance of a β-catenin-chromatin-remodeling network to ASD etiology.
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Affiliation(s)
- Brian J. O’Roak
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Laura Vives
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Wenqing Fu
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Jarrett D. Egertson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Ian B. Stanaway
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Ian G. Phelps
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
- Seattle Children’s Hospital, Seattle, WA 98105, USA
| | - Gemma Carvill
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
- Seattle Children’s Hospital, Seattle, WA 98105, USA
| | - Akash Kumar
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Choli Lee
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Katy Ankenman
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA
| | - Jeff Munson
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA
| | - Joseph B. Hiatt
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Emily H. Turner
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Roie Levy
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Diana R. O’Day
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Niklas Krumm
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Bradley P. Coe
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Beth K. Martin
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Elhanan Borenstein
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
- Department of Computer Science and Engineering, University of Washington, Seattle, WA 98195, USA
- Santa Fe Institute, Santa Fe, NM 87501, USA
| | - Deborah A. Nickerson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Heather C. Mefford
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
- Seattle Children’s Hospital, Seattle, WA 98105, USA
| | - Dan Doherty
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98195, USA
- Seattle Children’s Hospital, Seattle, WA 98105, USA
| | - Joshua M. Akey
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Raphael Bernier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA
| | - Evan E. Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
- Howard Hughes Medical Institute, Seattle, WA 98195, USA
| | - Jay Shendure
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
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27
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An association study of sequence variants in the forkhead box P2 (FOXP2) gene and adulthood attention-deficit/hyperactivity disorder in two European samples. Psychiatr Genet 2012; 22:155-60. [DOI: 10.1097/ypg.0b013e328353957e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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28
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Laffin JJS, Raca G, Jackson CA, Strand EA, Jakielski KJ, Shriberg LD. Novel candidate genes and regions for childhood apraxia of speech identified by array comparative genomic hybridization. Genet Med 2012; 14:928-36. [PMID: 22766611 DOI: 10.1038/gim.2012.72] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE The goal of this study was to identify new candidate genes and genomic copy-number variations associated with a rare, severe, and persistent speech disorder termed childhood apraxia of speech. Childhood apraxia of speech is the speech disorder segregating with a mutation in FOXP2 in a multigenerational London pedigree widely studied for its role in the development of speech-language in humans. METHODS A total of 24 participants who were suspected to have childhood apraxia of speech were assessed using a comprehensive protocol that samples speech in challenging contexts. All participants met clinical-research criteria for childhood apraxia of speech. Array comparative genomic hybridization analyses were completed using a customized 385K Nimblegen array (Roche Nimblegen, Madison, WI) with increased coverage of genes and regions previously associated with childhood apraxia of speech. RESULTS A total of 16 copy-number variations with potential consequences for speech-language development were detected in 12 or half of the 24 participants. The copy-number variations occurred on 10 chromosomes, 3 of which had two to four candidate regions. Several participants were identified with copy-number variations in two to three regions. In addition, one participant had a heterozygous FOXP2 mutation and a copy-number variation on chromosome 2, and one participant had a 16p11.2 microdeletion and copy-number variations on chromosomes 13 and 14. CONCLUSION Findings support the likelihood of heterogeneous genomic pathways associated with childhood apraxia of speech.
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Bacon C, Rappold GA. The distinct and overlapping phenotypic spectra of FOXP1 and FOXP2 in cognitive disorders. Hum Genet 2012; 131:1687-98. [PMID: 22736078 PMCID: PMC3470686 DOI: 10.1007/s00439-012-1193-z] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 06/11/2012] [Indexed: 12/15/2022]
Abstract
Rare disruptions of FOXP2 have been strongly implicated in deficits in language development. Research over the past decade has suggested a role in the formation of underlying neural circuits required for speech. Until recently no evidence existed to suggest that the closely related FOXP1 gene played a role in neurodevelopmental processes. However, in the last few years, novel rare disruptions in FOXP1 have been reported in multiple cases of cognitive dysfunction, including intellectual disability and autism spectrum disorder, together with language impairment. As FOXP1 and FOXP2 form heterodimers for transcriptional regulation, one may assume that they co-operate in common neurodevelopmental pathways through the co-regulation of common targets. Here we compare the phenotypic consequences of FOXP1 and FOXP2 impairment, drawing on well-known studies from the past as well as recent exciting findings and consider what these tell us regarding the functions of these two genes in neural development.
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Affiliation(s)
- Claire Bacon
- Department of Human Molecular Genetics, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Gudrun A. Rappold
- Department of Human Molecular Genetics, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
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Wong PCM, Morgan-Short K, Ettlinger M, Zheng J. Linking neurogenetics and individual differences in language learning: the dopamine hypothesis. Cortex 2012; 48:1091-102. [PMID: 22565204 DOI: 10.1016/j.cortex.2012.03.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 01/27/2012] [Accepted: 03/21/2012] [Indexed: 11/19/2022]
Abstract
Fundamental advances in neuroscience have come from investigations into neuroplasticity and learning. These investigations often focus on identifying universal principles across different individuals of the same species. Increasingly, individual differences in learning success have also been observed, such that any seemingly universal principle might only be applicable to a certain extent within a particular learner. One potential source of this variation is individuals' genetic differences. Adult language learning provides a unique opportunity for understanding individual differences and genetic bases of neuroplasticity because of the large individual differences in learning success that have already been documented, and because of the body of empirical work connecting language learning and neurocognition. In this article, we review the literature on the genetic bases of neurocognition, especially studies examining polymorphisms of dopamine (DA)-related genes and procedural learning. This review leads us to hypothesize that there may be an association between DA-related genetic variation and language learning differences. If this hypothesis is supported by future empirical findings we suggest that it may point to neurogenetic markers that allow for language learning to be personalized.
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Affiliation(s)
- Patrick C M Wong
- Roxelyn and Richard Pepper Department of Communication Sciences & Disorders, Northwestern University, Evanston, IL, USA.
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Palka C, Alfonsi M, Mohn A, Cerbo R, Guanciali Franchi P, Fantasia D, Morizio E, Stuppia L, Calabrese G, Zori R, Chiarelli F, Palka G. Mosaic 7q31 deletion involving FOXP2 gene associated with language impairment. Pediatrics 2012; 129:e183-8. [PMID: 22144704 DOI: 10.1542/peds.2010-2094] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We report on a 10-year-old patient with childhood apraxia of speech (CAS) and mild dysmorphic features. Although multiple karyotypes were reported as normal, a bacterial artificial chromosome array comparative genomic hybridization revealed the presence of a de novo 14.8-Mb mosaic deletion of chromosome 7q31. The deleted region involved several genes, including FOXP2, which has been associated with CAS. Interestingly, the deletion reported here was observed in about 50% of cells, which is the first case of mosaicism in a 7q31 deletion. Despite the presence of the deletion in only 50% of cells, the phenotype of the patient was not milder than other published cases. To date, 6 cases with a deletion of 9.1-20 Mb involving the FOXP2 gene have been reported, suggesting a new contiguous gene deletion syndrome characterized mainly by CAS caused by haploinsufficiency of the genes encompassed in the 7q critical region. This report suggests that children found with a deletion involving the FOXP2 region should be evaluated for CAS and that analysis of the FOXP2 gene including array comparative genomic hybridization should be considered in selected patients with CAS. Mosaic deletions in this area may also be considered as causative of CAS.
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Affiliation(s)
- Chiara Palka
- Department of Oral Sciences, Nano and Biotechnologies, G. D'Annunzio University, Via dei Vestini 31, 66100 Chieti, Italy.
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Affiliation(s)
| | - Dennis Drayna
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892;
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Patel C, Cooper-Charles L, McMullan DJ, Walker JM, Davison V, Morton J. Translocation breakpoint at 7q31 associated with tics: further evidence for IMMP2L as a candidate gene for Tourette syndrome. Eur J Hum Genet 2011; 19:634-9. [PMID: 21386874 DOI: 10.1038/ejhg.2010.238] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Gilles de la Tourette syndrome is a complex neuropsychiatric disorder with a strong genetic basis. We identified a male patient with Tourette syndrome-like tics and an apparently balanced de novo translocation [46,XY,t(2;7)(p24.2;q31)]. Further analysis using array comparative genomic hybridisation (CGH) revealed a cryptic deletion at 7q31.1-7q31.2. Breakpoints disrupting this region have been reported in one isolated and one familial case of Tourette syndrome. In our case, IMMP2L, a gene coding for a human homologue of the yeast inner mitochondrial membrane peptidase subunit 2, was disrupted by the breakpoint on 7q31.1, with deletion of exons 1-3 of the gene. The IMMP2L gene has previously been proposed as a candidate gene for Tourette syndrome, and our case provides further evidence of its possible role in the pathogenesis. The deleted region (7q31.1-7q31.2) of 7.2 Mb of genomic DNA also encompasses numerous genes, including FOXP2, associated with verbal dyspraxia, and the CFTR gene.
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Affiliation(s)
- Chirag Patel
- Department of Clinical Genetics, Birmingham Women's Hospital NHS Foundation Trust, Birmingham, UK.
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Tamiji J, Crawford DA. The neurobiology of lipid metabolism in autism spectrum disorders. Neurosignals 2011; 18:98-112. [PMID: 21346377 DOI: 10.1159/000323189] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 11/29/2010] [Indexed: 01/17/2023] Open
Abstract
Autism is a neurodevelopmental disorder characterized by impairments in communication and reciprocal social interaction, coupled with repetitive behavior, which typically manifests by 3 years of age. Multiple genes and early exposure to environmental factors are the etiological determinants of the disorder that contribute to variable expression of autism-related traits. Increasing evidence indicates that altered fatty acid metabolic pathways may affect proper function of the nervous system and contribute to autism spectrum disorders. This review provides an overview of the reported abnormalities associated with the synthesis of membrane fatty acids in individuals with autism as a result of insufficient dietary supplementation or genetic defects. Moreover, we discuss deficits associated with the release of arachidonic acid from the membrane phospholipids and its subsequent metabolism to bioactive prostaglandins via phospholipase A(2)-cyclooxygenase biosynthetic pathway in autism spectrum disorders. The existing evidence for the involvement of lipid neurobiology in the pathology of neurodevelopmental disorders such as autism is compelling and opens up an interesting possibility for further investigation of this metabolic pathway.
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Affiliation(s)
- Javaneh Tamiji
- Department of Biology, York University, Toronto, Ont., Canada
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Wilkins JF, Úbeda F. Diseases associated with genomic imprinting. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 101:401-45. [PMID: 21507360 DOI: 10.1016/b978-0-12-387685-0.00013-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Genomic imprinting is the phenomenon where the expression of a locus differs between the maternally and paternally inherited alleles. Typically, this manifests as transcriptional silencing of one of the alleles, although many genes are imprinted in a tissue- or isoform-specific manner. Diseases associated with imprinted genes include various cancers, disorders of growth and metabolism, and disorders in neurodevelopment, cognition, and behavior, including certain major psychiatric disorders. In many cases, the disease phenotypes associated with dysfunction at particular imprinted loci can be understood in terms of the evolutionary processes responsible for the origin of imprinting. Imprinted gene expression represents the outcome of an intragenomic evolutionary conflict, where natural selection favors different expression strategies for maternally and paternally inherited alleles. This conflict is reasonably well understood in the context of the early growth effects of imprinted genes, where paternally inherited alleles are selected to place a greater demand on maternal resources than are maternally inherited alleles. Less well understood are the origins of imprinted gene expression in the brain, and their effects on cognition and behavior. This chapter reviews the genetic diseases that are associated with imprinted genes, framed in terms of the evolutionary pressures acting on gene expression at those loci. We begin by reviewing the phenomenon and evolutionary origins of genomic imprinting. We then discuss diseases that are associated with genetic or epigenetic defects at particular imprinted loci, many of which are associated with abnormalities in growth and/or feeding behaviors that can be understood in terms of the asymmetric pressures of natural selection on maternally and paternally inherited alleles. We next described the evidence for imprinted gene effects on adult cognition and behavior, and the possible role of imprinted genes in the etiology of certain major psychiatric disorders. Finally, we conclude with a discussion of how imprinting, and the evolutionary-genetic conflicts that underlie it, may enhance both the frequency and morbidity of certain types of diseases.
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Newbury DF, Monaco AP. Genetic advances in the study of speech and language disorders. Neuron 2010; 68:309-20. [PMID: 20955937 PMCID: PMC2977079 DOI: 10.1016/j.neuron.2010.10.001] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2010] [Indexed: 11/29/2022]
Abstract
Developmental speech and language disorders cover a wide range of childhood conditions with overlapping but heterogeneous phenotypes and underlying etiologies. This characteristic heterogeneity hinders accurate diagnosis, can complicate treatment strategies, and causes difficulties in the identification of causal factors. Nonetheless, over the last decade, genetic variants have been identified that may predispose certain individuals to different aspects of speech and language difficulties. In this review, we summarize advances in the genetic investigation of stuttering, speech-sound disorder (SSD), specific language impairment (SLI), and developmental verbal dyspraxia (DVD). We discuss how the identification and study of specific genes and pathways, including FOXP2, CNTNAP2, ATP2C2, CMIP, and lysosomal enzymes, may advance our understanding of the etiology of speech and language disorders and enable us to better understand the relationships between the different forms of impairment across the spectrum.
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Affiliation(s)
- D F Newbury
- Wellcome Trust Centre for Human Genetics, Headington, Oxford, UK.
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Addis L, Friederici AD, Kotz SA, Sabisch B, Barry J, Richter N, Ludwig AA, Rübsamen R, Albert FW, Pääbo S, Newbury DF, Monaco AP. A locus for an auditory processing deficit and language impairment in an extended pedigree maps to 12p13.31-q14.3. GENES BRAIN AND BEHAVIOR 2010; 9:545-61. [PMID: 20345892 PMCID: PMC2948670 DOI: 10.1111/j.1601-183x.2010.00583.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Despite the apparent robustness of language learning in humans, a large number of children still fail to develop appropriate language skills despite adequate means and opportunity. Most cases of language impairment have a complex etiology, with genetic and environmental influences. In contrast, we describe a three-generation German family who present with an apparently simple segregation of language impairment. Investigations of the family indicate auditory processing difficulties as a core deficit. Affected members performed poorly on a nonword repetition task and present with communication impairments. The brain activation pattern for syllable duration as measured by event-related brain potentials showed clear differences between affected family members and controls, with only affected members displaying a late discrimination negativity. In conjunction with psychoacoustic data showing deficiencies in auditory duration discrimination, the present results indicate increased processing demands in discriminating syllables of different duration. This, we argue, forms the cognitive basis of the observed language impairment in this family. Genome-wide linkage analysis showed a haplotype in the central region of chromosome 12 which reaches the maximum possible logarithm of odds ratio (LOD) score and fully co-segregates with the language impairment, consistent with an autosomal dominant, fully penetrant mode of inheritance. Whole genome analysis yielded no novel inherited copy number variants strengthening the case for a simple inheritance pattern. Several genes in this region of chromosome 12 which are potentially implicated in language impairment did not contain polymorphisms likely to be the causative mutation, which is as yet unknown.
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Affiliation(s)
- L Addis
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
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Abstract
Specific language impairment (SLI) is defined as an unexpected and persistent impairment in language ability despite adequate opportunity and intelligence and in the absence of any explanatory medical conditions. This condition is highly heritable and affects between 5% and 8% of pre-school children. Over the past few years, investigations have begun to uncover genetic factors that may contribute to susceptibility to language impairment. So far, variants in four specific genes have been associated with spoken language disorders - forkhead box P2 (FOXP2) and contactin-associated protein-like 2 (CNTNAP2) on chromosome7 and calcium-transporting ATPase 2C2 (ATP2C2) and c-MAF inducing protein (CMIP) on chromosome 16. Here, we describe the different ways in which these genes were identified as candidates for language impairment. We discuss how characterization of these genes, and the pathways in which they are involved, may enhance our understanding of language disorders and improve our understanding of the biological foundations of language acquisition.
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Affiliation(s)
- Dianne F Newbury
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Headington, Oxford OX3 7BN, UK.
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Unravelling neurogenetic networks implicated in developmental language disorders. Biochem Soc Trans 2009; 37:1263-9. [DOI: 10.1042/bst0371263] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Childhood syndromes disturbing language development are common and display high degrees of heritability. In most cases, the underlying genetic architecture is likely to be complex, involving multiple chromosomal loci and substantial heterogeneity, which makes it difficult to track down the crucial genomic risk factors. Investigation of rare Mendelian phenotypes offers a complementary route for unravelling key neurogenetic pathways. The value of this approach is illustrated by the discovery that heterozygous FOXP2 (where FOX is forkhead box) mutations cause an unusual monogenic disorder, characterized by problems with articulating speech along with deficits in expressive and receptive language. FOXP2 encodes a regulatory protein, belonging to the forkhead box family of transcription factors, known to play important roles in modulating gene expression in development and disease. Functional genetics using human neuronal models suggest that the different FOXP2 isoforms generated by alternative splicing have distinct properties and may act to regulate each other's activity. Such investigations have also analysed the missense and nonsense mutations found in cases of speech and language disorder, showing that they alter intracellular localization, DNA binding and transactivation capacity of the mutated proteins. Moreover, in the brains of mutant mice, aetiological mutations have been found to disrupt the synaptic plasticity of Foxp2-expressing circuitry. Finally, although mutations of FOXP2 itself are rare, the downstream networks which it regulates in the brain appear to be broadly implicated in typical forms of language impairment. Thus, through ongoing identification of regulated targets and interacting co-factors, this gene is providing the first molecular entry points into neural mechanisms that go awry in language-related disorders.
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Tomblin JB, O'Brien M, Shriberg LD, Williams C, Murray J, Patil S, Bjork J, Anderson S, Ballard K. Language features in a mother and daughter of a chromosome 7;13 translocation involving FOXP2. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2009; 52:1157-74. [PMID: 19797137 PMCID: PMC2760059 DOI: 10.1044/1092-4388(2009/07-0162)] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
PURPOSE The aims of this study were (a) to locate the breakpoints of a balanced translocation (7;13) within a mother (B) and daughter (T); (b) to describe the language and cognitive skills of B and T; and (c) to compare this profile with affected family members of the KE family who have a mutation within FOXP2. METHOD The breakpoint locations for T and B were identified by use of fluorescent in situ hybridization analysis followed by DNA sequencing using long-range polymer chain reaction amplification methods. The cognitive and language characteristics were obtained via the use of standardized tests of intelligence, receptive and expressive vocabulary and sentence use, and a spontaneous language sample. RESULTS The translocation breakpoints in T and B were found in FOXP2 on chromosome 7 and in RFC3 on chromosome 13. T and B's pattern of relative strengths and weaknesses across their cognitive and language performance was found to be similar to descriptions of the affected KE family members. CONCLUSIONS Prior reports of individuals with chromosomal rearrangements of FOXP2 have emphasized their speech impairment. This study provides additional evidence that language-in particular, grammar-is likely to be influenced by abnormalities of FOXP2 function.
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Affiliation(s)
- J Bruce Tomblin
- Department of Speech Pathology and Audiology, University of Iowa, WJSHC, Iowa City, IA, USA.
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Fisher SE, Scharff C. FOXP2 as a molecular window into speech and language. Trends Genet 2009; 25:166-77. [PMID: 19304338 DOI: 10.1016/j.tig.2009.03.002] [Citation(s) in RCA: 293] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Revised: 03/02/2009] [Accepted: 03/02/2009] [Indexed: 01/07/2023]
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Detailed characterization of, and clinical correlations in, 10 patients with distal deletions of chromosome 9p. Genet Med 2009; 10:599-611. [PMID: 18641517 DOI: 10.1097/gim.0b013e31817e2bde] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
PURPOSE Deletions of distal 9p are associated with trigonocephaly, mental retardation, dysmorphic facial features, cardiac anomalies, and abnormal genitalia. Previous studies identified a proposed critical region for the consensus phenotype in band 9p23, between 11.8 Mb and 16 Mb from the 9p telomere. Here we report 10 new patients with 9p deletions; 9 patients have clinical features consistent with 9p- syndrome, but possess terminal deletions smaller than most reported cases, whereas one individual lacks the 9p- phenotype and shows a 140-kb interstitial telomeric deletion inherited from his mother. METHODS We combined fluorescence in situ hybridization and microarray analyses to delineate the size of each deletion. RESULTS The deletion sizes vary from 800 kb to 12.4 Mb in our patients with clinically relevant phenotypes. Clinical evaluation and comparison showed little difference in physical features with regard to the deletion sizes. Severe speech and language impairment were observed in all patients with clinically relevant phenotypes. CONCLUSION The smallest deleted region common to our patients who demonstrate a phenotype consistent with 9p- is <2 Mb of 9pter, which contains six known genes. These genes may contribute to some of the cardinal features of 9p deletion syndrome.
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Ghika J. Paleoneurology: Neurodegenerative diseases are age-related diseases of specific brain regions recently developed by homo sapiens. Med Hypotheses 2008; 71:788-801. [DOI: 10.1016/j.mehy.2008.05.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 05/01/2008] [Accepted: 05/04/2008] [Indexed: 12/31/2022]
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Shriberg LD, Jakielski KJ, El-Shanti H. Breakpoint localization using array-CGH in three siblings with an unbalanced 4q;16q translocation and childhood apraxia of speech (CAS). Am J Med Genet A 2008; 146A:2227-33. [PMID: 18671280 DOI: 10.1002/ajmg.a.32363] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report clinical, cytogenetic, and comparative genomic hybridization findings for three siblings with an unbalanced 4q;16q translocation, minor malformations, and cognitive abnormalities, including childhood apraxia of speech, a rare, severe motor speech disorder. Breakpoint findings indicate that in addition to possible contributions from duplicated genes on chromosome 16, haploinsufficiency of one or more of 11 genes deleted in the telomeric region of the long arm of chromosome 4 is the likely cause of the speech disorder, the associated impairments in cognition and language, and the dysmorphic features. The present findings are the first to document childhood apraxia of speech in a multiplex family using contemporary speech measures. We suggest that genotype-phenotype studies of childhood apraxia of speech occurring in complex neurodevelopmental disorders can elucidate the pathophysiology of this disorder.
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Gibson CJ, Gruen JR. The human lexinome: genes of language and reading. JOURNAL OF COMMUNICATION DISORDERS 2008; 41:409-20. [PMID: 18466916 PMCID: PMC2488410 DOI: 10.1016/j.jcomdis.2008.03.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Accepted: 03/12/2008] [Indexed: 05/26/2023]
Abstract
UNLABELLED Within the human genome, genetic mapping studies have identified 10 regions of different chromosomes, known as DYX loci, in genetic linkage with dyslexia, and two, known as SLI loci, in genetic linkage with Specific Language Impairment (SLI). Further genetic studies have identified four dyslexia genes within the DYX loci: DYX1C1 on 15q, KIAA0319 and DCDC2 on 6p22, and ROBO1 on 13q. FOXP2 on 7q has been implicated in the development of Speech-Language Disorder. No genes for Specific Language Impairment have yet been identified within the two SLI loci. Functional studies have shown that all four dyslexia genes play roles in brain development, and ongoing molecular studies are attempting to elucidate how these genes exert their effects at a subcellular level. Taken together, these genes and loci likely represent only a fraction of the human lexinome, a term we introduce here to refer to the collection of all the genetic and protein elements involved in the development of human language, expression, and reading. LEARNING OUTCOMES The reader will become familiar with (i) methods for identifying genes for complex diseases, (ii) the application of these methods in the elucidation of genes underlying disorders of language and reading, and (iii) the cellular pathways through which polymorphisms in these genes may contribute to the development of the disorders.
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Affiliation(s)
- Christopher J. Gibson
- Department of Pediatrics, Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT, USA
| | - Jeffrey R. Gruen
- Department of Genetics and Investigative Medicine Program, Yale University School of Medicine, New Haven, CT, USA
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Genes, Brains, and Language: An Epistemological Examination of how Genes can Underlie Human Cognitive Behavior. REVIEW OF GENERAL PSYCHOLOGY 2008. [DOI: 10.1037/1089-2680.12.2.170] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
How do genes encode for the formation of morphological structures such as the brain? Can genetic material also encode for behavior such as cognition, language, or culture? For many years, evolutionary biologists as well as scholars who work within extrabiological fields such as psychology, linguistics, and archaeology could only answer the above two questions in a speculative manner. This is because until recently, empirical observations on how genes underlie anatomy or behavior were generally lacking. This situation has now changed. Several genes ( MCPH1-MCPH6) have been implicated in the regulation of brain size and a first gene (the FOXP2 gene) has been identified that might underlie linguistic behavior. These discoveries allow us to finally test some of the long-standing theoretical assumptions on how genes do or do not determine morphology and behavior.
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Peter B, Stoel-Gammon C. Central timing deficits in subtypes of primary speech disorders. CLINICAL LINGUISTICS & PHONETICS 2008; 22:171-198. [PMID: 18307084 DOI: 10.1080/02699200701799825] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Childhood apraxia of speech (CAS) is a proposed speech disorder subtype that interferes with motor planning and/or programming, affecting prosody in many cases. Pilot data (Peter & Stoel-Gammon, 2005) were consistent with the notion that deficits in timing accuracy in speech and music-related tasks may be associated with CAS. This study replicated and expanded earlier findings. Eleven children with speech disorders and age-and gender-matched controls participated in non-word imitation, clapped rhythm imitation, and paced repetitive tapping tasks. Results suggest a central timing deficit, expressed in both the oral and the limb modality, and observable in two different types of timing measures, overall rhythmic structures and small-scale durations. Associations among timing measures were strongest in the participants with speech disorders, who also showed lower timing accuracy than the controls in all measures. The number of observed CAS characteristics was associated with timing deficits.
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Affiliation(s)
- Beate Peter
- Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98105, USA.
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Kaur A, Dhillon S, Garg PD, Singh JR. Ring chromosome 7 in an Indian woman. JOURNAL OF INTELLECTUAL & DEVELOPMENTAL DISABILITY 2008; 33:87-94. [PMID: 18300171 DOI: 10.1080/13668250701829829] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND Ring chromosome 7 [r(7)] is a rare cytogenetic aberration, with only 16 cases (including 3 females) reported in the literature to date. This is the first reported case of r(7) from India. METHOD Clinical and cytogenetic investigations were carried out in an adult female with microcephaly and intellectual disability. RESULTS Ring chromosome 7 was observed in 10% of the metaphases (46,XX,r(7)/46,XX). The clinical findings revealed microcephaly, growth delay, and dark pigmented naevi. CONCLUSION The mosaicism for a chromosomal anomaly is an under-recognised cause of intellectual disability.
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Affiliation(s)
- Anupam Kaur
- Centre for Genetic Disorders, Guru Nanak Dev University, Amritsar, India.
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Fatemi SH, Reutiman TJ, Folsom TD, Huang H, Oishi K, Mori S, Smee DF, Pearce DA, Winter C, Sohr R, Juckel G. Maternal infection leads to abnormal gene regulation and brain atrophy in mouse offspring: implications for genesis of neurodevelopmental disorders. Schizophr Res 2008; 99:56-70. [PMID: 18248790 PMCID: PMC2312390 DOI: 10.1016/j.schres.2007.11.018] [Citation(s) in RCA: 185] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Revised: 10/29/2007] [Accepted: 11/05/2007] [Indexed: 12/15/2022]
Abstract
Prenatal viral infection has been associated with development of schizophrenia and autism. Our laboratory has previously shown that viral infection causes deleterious effects on brain structure and function in mouse offspring following late first trimester (E9) administration of influenza virus. We hypothesized that late second trimester infection (E18) in mice may lead to a different pattern of brain gene expression and structural defects in the developing offspring. C57BL6J mice were infected on E18 with a sublethal dose of human influenza virus or sham-infected using vehicle solution. Male offsping of the infected mice were collected at P0, P14, P35 and P56, their brains removed and prefrontal cortex, hippocampus and cerebellum dissected and flash frozen. Microarray, qRT-PCR, DTI and MRI scanning, western blotting and neurochemical analysis were performed to detect differences in gene expression and brain atrophy. Expression of several genes associated with schizophrenia or autism including Sema3a, Trfr2 and Vldlr were found to be altered as were protein levels of Foxp2. E18 infection of C57BL6J mice with a sublethal dose of human influenza virus led to significant gene alterations in frontal, hippocampal and cerebellar cortices of developing mouse progeny. Brain imaging revealed significant atrophy in several brain areas and white matter thinning in corpus callosum. Finally, neurochemical analysis revealed significantly altered levels of serotonin (P14, P35), 5-Hydroxyindoleacetic acid (P14) and taurine (P35). We propose that maternal infection in mouse provides an heuristic animal model for studying the environmental contributions to genesis of schizophrenia and autism, two important examples of neurodevelopmental disorders.
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Affiliation(s)
- S. Hossein Fatemi
- Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455,Department of Pharmacology, University of Minnesota Medical School, 310 Church St. SE, Minneapolis, MN 55455,Department of Neuroscience, University of Minnesota Medical School, 310 Church St. SE, Minneapolis, MN 55455
| | - Teri J. Reutiman
- Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455
| | - Timothy D. Folsom
- Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455
| | - Hao Huang
- Department of Radiology, Division of NMR, Johns Hopkins University, School of Medicine, 720 Rutland Avenue, Baltimore, MD 21287
| | - Kenichi Oishi
- Department of Radiology, Division of NMR, Johns Hopkins University, School of Medicine, 720 Rutland Avenue, Baltimore, MD 21287
| | - Susumu Mori
- Department of Radiology, Division of NMR, Johns Hopkins University, School of Medicine, 720 Rutland Avenue, Baltimore, MD 21287
| | - Donald F. Smee
- Institute for Antiviral Research, Department of Animal, Dairy and Veterinary Sciences, Utah State University, 5600 Old Main Hill, Logan, Utah, 84322
| | - David A. Pearce
- Center for Aging and Developmental Biology, Aab Institute of Biomedical Sciences, Department of Biochemistry and Biophysics, Department of Neurobiology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 645, Rochester, NY 14627
| | - Christine Winter
- Department of Psychiatry and Psychotherapy, Charité Campus Mitte, University Medicine, Berlin, 10117, Germany
| | - Reinhard Sohr
- Institute of Pharmacology and Toxicology, Charité University Medicine, Dorotheenstrasse 94, D 10117, Berlin, Germany
| | - Georg Juckel
- Department of Psychiatry - Psychotherapy - Psychosomatic Medicine, Ruhr University, 1 Alexandrinenstr. 44791 Bochum, Germany
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Nielsen R, Hellmann I, Hubisz M, Bustamante C, Clark AG. Recent and ongoing selection in the human genome. Nat Rev Genet 2007; 8:857-68. [PMID: 17943193 PMCID: PMC2933187 DOI: 10.1038/nrg2187] [Citation(s) in RCA: 344] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The recent availability of genome-scale genotyping data has led to the identification of regions of the human genome that seem to have been targeted by selection. These findings have increased our understanding of the evolutionary forces that affect the human genome, have augmented our knowledge of gene function and promise to increase our understanding of the genetic basis of disease. However, inferences of selection are challenged by several confounding factors, especially the complex demographic history of human populations, and concordance between studies is variable. Although such studies will always be associated with some uncertainty, steps can be taken to minimize the effects of confounding factors and improve our interpretation of their findings.
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Affiliation(s)
- Rasmus Nielsen
- Center for Comparative Genomics, University of Copenhagen, Universitetsparken 15, 2100 Kbh Ø, Denmark.
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