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Rinne N, Wikman P, Sahari E, Salmi J, Einarsdóttir E, Kere J, Alho K. Developmental dyslexia susceptibility genes DNAAF4, DCDC2, and NRSN1 are associated with brain function in fluently reading adolescents and young adults. Cereb Cortex 2024; 34:bhae144. [PMID: 38610086 PMCID: PMC11014888 DOI: 10.1093/cercor/bhae144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 03/16/2024] [Accepted: 03/17/2024] [Indexed: 04/14/2024] Open
Abstract
Reading skills and developmental dyslexia, characterized by difficulties in developing reading skills, have been associated with brain anomalies within the language network. Genetic factors contribute to developmental dyslexia risk, but the mechanisms by which these genes influence reading skills remain unclear. In this preregistered study (https://osf.io/7sehx), we explored if developmental dyslexia susceptibility genes DNAAF4, DCDC2, NRSN1, and KIAA0319 are associated with brain function in fluently reading adolescents and young adults. Functional MRI and task performance data were collected during tasks involving written and spoken sentence processing, and DNA sequence variants of developmental dyslexia susceptibility genes previously associated with brain structure anomalies were genotyped. The results revealed that variation in DNAAF4, DCDC2, and NRSN1 is associated with brain activity in key language regions: the left inferior frontal gyrus, middle temporal gyrus, and intraparietal sulcus. Furthermore, NRSN1 was associated with task performance, but KIAA0319 did not yield any significant associations. Our findings suggest that individuals with a genetic predisposition to developmental dyslexia may partly employ compensatory neural and behavioral mechanisms to maintain typical task performance. Our study highlights the relevance of these developmental dyslexia susceptibility genes in language-related brain function, even in individuals without developmental dyslexia, providing valuable insights into the genetic factors influencing language processing.
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Affiliation(s)
- Nea Rinne
- Department of Psychology and Logopedics, University of Helsinki, Haartmaninkatu 3, 00014 Helsinki, Finland
| | - Patrik Wikman
- Department of Psychology and Logopedics, University of Helsinki, Haartmaninkatu 3, 00014 Helsinki, Finland
| | - Elisa Sahari
- Department of Psychology and Speech-Language Pathology, University of Turku, Assistentinkatu 7, 20500 Turku, Finland
| | - Juha Salmi
- Department of Neuroscience and Biomedical Engineering, Otakaari 3, Aalto University, (AALTO), P.O. BOX 00076, Espoo, Finland
| | - Elisabet Einarsdóttir
- Science for Life Laboratory, Department of Gene Technology, KTH-Royal Institute of Technology, SE-171 21, Solna, Sweden
| | - Juha Kere
- Department of Biosciences and Nutrition, Karolinska Institutet, H7 Medicin, Huddinge, Sweden
- Folkhälsan Research Center, and Stem Cells and Metabolism Research Program (STEMM), University of Helsinki, PL 63, Haartmaninkatu 8, Helsinki, Finland
| | - Kimmo Alho
- Department of Psychology and Logopedics, University of Helsinki, Haartmaninkatu 3, 00014 Helsinki, Finland
- Advanced Magnetic Imaging Centre, Aalto NeuroImaging, Aalto University, Espoo, Finland
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Kalashnikova TP, Satyukova MO, Anisimov GV, Karakulova YV. [Genetic background of dyslexia and dysgraphy in children]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:48-52. [PMID: 37315241 DOI: 10.17116/jnevro202312305148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The review is devoted to one of the current problems of pediatric neurology - reading and writing disorders in children as part of a partial developmental disorder. With the development of neuroscience, the paradigm of «brain damage» in the understanding of a number of pathological conditions was replaced by the concept of «evolutionary neurology». The dominance of the ontogenetic approach caused the appearance of a new section in ICD-11 - «Neurodevelopmental disorders». Twenty-one genes associated with the acquisition of reading and writing skills have been identified. Modern studies demonstrate the connection of neuropsychological prerequisites for reading and writing, and clinical phenotypes of dyslexia with changes in specific loci. It is assumed that there are different molecular genetic bases for dyslexia and dysgraphia depending on ethnicity, orthographic features of language, including logographic features. Pleiotropy of genes is a cause of comorbidity of reading and writing disorders with attention deficit and hyperactivity disorder, specific speech articulation disorders, and dyscalculia. A key function of many of the identified genes is their involvement in the processes of neurogenesis. Their dysfunctions cause atypical neuronal migration, ectopic formation, inadequate axonal growth, and dendrite branching at the early stage of brain development. Morphological changes can distort the correct distribution and/or integration of linguistic stimuli in critical brain areas, leading to abnormalities in phonology, semantics, spelling, and general reading comprehension. The knowledge gained can form the basis for the development of risk models for dysgraphia and dyslexia formation and be used as a diagnostic and/or screening tool, which is important for evidence-based correction, optimization of academic performance, and mitigation of psychosocial consequences.
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Affiliation(s)
| | | | - G V Anisimov
- First Medico-Pedagogical Center «Lingua Bona», Perm, Russia
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Xu Z, Chen Z, Shen T, Chen L, Tan T, Gao C, Chen B, Yuan Y, Zhang Z. The impact of HTR1A and HTR1B methylation combined with stress/genotype on early antidepressant efficacy. Psychiatry Clin Neurosci 2022; 76:51-57. [PMID: 34773671 DOI: 10.1111/pcn.13314] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 10/11/2021] [Accepted: 11/03/2021] [Indexed: 12/21/2022]
Abstract
AIMS Antidepressants are effective in the treatment of major depressive disorder (MDD), while many patients fail to respond to antidepressants. Both 5-HT1A (HTR1A) and 5-HT1B (HTR1B) receptors play an important role in antidepressant activity. Meanwhile, DNA methylation is associated with MDD and antidepressant efficacy. In this study we investigate the influence of HTR1A and HTR1B methylation combined with stress/genotype on antidepressant efficacy. METHODS A total of 291 MDD patients and 100 healthy controls received the Life Events Scale (LES) and the Childhood Trauma Questionnaire (CTQ) as stress assessment. Eight single nucleotide polymorphisms (SNPs) of HTR1A and HTR1B involved in antidepressant mechanisms were tested. Methylation status in 181 cytosine-phosphate-guanine (CpG) sites of HTR1A and HTR1B were assessed. All MDD patients were divided into response (RES) and non-response (NRES) after 2 weeks of antidepressant treatment. Logistic regression was conducted for interactions between methylation, NLES/CTQ score and genotype. RESULTS Low HTR1A-2-143 methylation is connected with better antidepressant efficacy in subgroup. Low HTR1A-2-143 methylation combined with low CTQ score is related to better antidepressant efficacy. The interaction between high HTR1B methylation with the rs6298 AA/AG genotype affects better antidepressant efficacy. CONCLUSIONS HTR1A and HTR1B methylation combined with stress/genotype is associated with antidepressant efficacy.
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Affiliation(s)
- Zhi Xu
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Zimu Chen
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Tian Shen
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Lei Chen
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Tingting Tan
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Chenjie Gao
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Bingwei Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China
| | - Yonggui Yuan
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Zhijun Zhang
- Department of Neurology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China
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Wang T, He K, Blaney L, Chung JS. 17β-Estradiol (E2) may be involved in the mode of crustacean female sex hormone (CFSH) action in the blue crab, Callinectes sapidus. Front Endocrinol (Lausanne) 2022; 13:962576. [PMID: 35957817 PMCID: PMC9358259 DOI: 10.3389/fendo.2022.962576] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 06/28/2022] [Indexed: 11/23/2022] Open
Abstract
17β-estradiol (E2) has been proved to control reproduction, sexual differentiation, and the development of the secondary sexual characteristics of vertebrate females. In decapod crustacean species, crustacean female sex hormone (CFSH), a protein hormone, is required for developing adult-specific ovigerous setae for embryo brooding and gonophores for mating at the blue crab Callinectes sapidus puberty molting. However, it is unclear that whether the mode of CFSH action involves a vertebrate-type sex steroid hormone in crustaceans. To this end, E2 levels were first measured using a competitive ELISA in the hemolymph and the potential CFSH target tissues from both prepuberty and adult females; the presence of E2 was further confirmed with a liquid chromatography tandem mass spectrometry method. Then, the cDNAs of the following genes known to be associated with vertebrate steroidogenic pathways were isolated: StAR-related lipid transfer protein 3 (StAR3); 3β-hydroxysteroid dehydrogenase (3βHSD); two isoforms of 17β-hydroxysteroid dehydrogenase 8 (17βHSD8); and, estradiol-related receptor (ERR). RT-PCR analysis revealed that these genes were widely distributed in the eyestalk ganglia, hepatopancreas, brain, ovary, spermathecae, ovigerous and plumose setae tissues of adult females. The 17βHSD8 transcripts were localized in the follicle cells, the periphery of the nuclear membrane of primary oocytes, and yolk granules of the vitellogenic oocytes using in situ hybridization, and the corresponding protein was detected in the follicle cells and ooplasm of primary oocytes using immunohistochemistry. Furthermore, the adult females injected with CFSH-dsRNA (n = 30 times) had E2 and StAR3 transcripts levels lower in the ovigerous and plumose setae, spermathecae than controls. These results suggested that the mode of CFSH action in C. sapidus might involve E2 in these adult-female-specific tissues.
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Affiliation(s)
- Tao Wang
- Department of Marine Biotechnology & Institute of Marine and Environmental Technology, University of Maryland Baltimore County, Baltimore, MD, United States
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, United States
| | - Ke He
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD, United States
| | - Lee Blaney
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD, United States
| | - J. Sook Chung
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, United States
- *Correspondence: J. Sook Chung,
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Granocchio E, De Salvatore M, Bonanomi E, Sarti D. Sex-related differences in reading achievement. J Neurosci Res 2021; 101:668-678. [PMID: 34240762 DOI: 10.1002/jnr.24913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/14/2021] [Indexed: 01/11/2023]
Abstract
Over the last 40 years, ever-growing interest in sex-related differences in the human brain has led to a vast amount of literature on the subject, a small part of which relates to studies of differences in the ability to read. The data concerning typically developing children mainly come from school-based screening projects (Programme for International Student Assessment, INVALSI) and partially from the standardization of reading tests. These have revealed the existence of a gap in favor of females that primarily appears during adolescence and in situations of sociocultural disadvantage, usually explained on the basis of environmental factors such as socioeconomic status and gender-based education. Dyslexia is a neurodevelopmental disorder that is significantly more prevalent among males, a difference that neuroimaging and genetic studies have attributed to the presence of hormone-related protective factors in females, although it has been hypothesized that a different neurocognitive substrate may also be involved. However, the literature on the subject is still limited, and further studies of the interactions between genetic risk, environmental factors, and brain phenotypes are needed to clarify why females are better at performing reading tasks and less susceptible to dyslexia, regardless of their language or the educational system in the country in which they live. The aim of this mini-review was to describe the studies that have investigated sex-related differences in reading ability in both typically and atypically developing subjects.
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Affiliation(s)
- Elisa Granocchio
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marinella De Salvatore
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Elisa Bonanomi
- Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Daniela Sarti
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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Ohlsson Gotby V, Söder O, Frisén L, Serlachius E, Bölte S, Almqvist C, Larsson H, Lichtenstein P, Tammimies K. Hypogonadotrophic hypogonadism, delayed puberty and risk for neurodevelopmental disorders. J Neuroendocrinol 2019; 31:e12803. [PMID: 31630461 DOI: 10.1111/jne.12803] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 08/31/2019] [Accepted: 10/18/2019] [Indexed: 12/29/2022]
Abstract
Hypogonadotrophic hypogonadism (HH) is a rare disorder that manifests absent puberty and infertility. Genetic syndromes with hypogonadism, such as Klinefelter syndrome, are associated with an increased risk of neurodevelopmental disorders (NDDs). However, it is not clear whether patients with HH or transient delayed puberty in general, have an increased risk of NDDs. We performed a register-based study on a national cohort of 264 patients with HH and 7447 patients diagnosed with delayed puberty that was matched with 2640 and 74 470 controls, respectively. The outcome was defined as having any of the following NDD diagnoses: (i) autism spectrum disorder (ASD); (ii) attention deficit hyperactivity disorder (ADHD); or (iii) intellectual disability (ID). Additional sensitivity analyses were performed to control for different parental and birth variables, as well as diagnosed malformation syndromes and chromosomal anomalies (ie, Down's and Turner syndromes). Patients with HH had increased risk for being diagnosed with ASD (odds ratio [OR] = 5.7; 95% confidence interval [CI] = 2.6-12.6), ADHD (OR = 3.0; 95% CI = 1.8-5.1) and ID (OR = 18.0; 95% CI = 8.9-36.3) compared to controls. Patients with delayed puberty also had a significantly increased risk of being diagnosed with an NDD. These associations remained significant after adjustments. This is the first study to demonstrate a significant association between HH, delayed puberty and NDDs in a population-based cohort. Clinicians should be aware of the overlap between these disorders. Further studies should explore the mechanisms behind these associations.
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Affiliation(s)
- Vide Ohlsson Gotby
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Olle Söder
- Division of Pediatric Endocrinology, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Louise Frisén
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutete, Stockholm, Sweden
- Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| | - Eva Serlachius
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutete, Stockholm, Sweden
- Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| | - Sven Bölte
- Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
- Division of Neuropsychiatry, Department of Women's and Children's Health, Center of Neurodevelopmental Disorders at Karolinska Institutet (KIND), Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Catarina Almqvist
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- School of Medical Sciences, Örebro University, Örebro, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Kristiina Tammimies
- Division of Neuropsychiatry, Department of Women's and Children's Health, Center of Neurodevelopmental Disorders at Karolinska Institutet (KIND), Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
- Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
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7
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Krafnick AJ, Evans TM. Neurobiological Sex Differences in Developmental Dyslexia. Front Psychol 2019; 9:2669. [PMID: 30687153 PMCID: PMC6336691 DOI: 10.3389/fpsyg.2018.02669] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 12/12/2018] [Indexed: 12/13/2022] Open
Abstract
Understanding sex differences at the neurobiological level has become increasingly crucial in both basic and applied research. In the study of developmental dyslexia, early neuroimaging investigations were dominated by male-only or male-dominated samples, due at least in part to males being diagnosed more frequently. While recent studies more consistently balance the inclusion of both sexes, there has been little movement toward directly characterizing potential sex differences of the disorder. However, a string of recent work suggests that the brain basis of dyslexia may indeed be different in males and females. This potential sex difference has implications for existing models of dyslexia, and would inform approaches to the remediation of reading difficulties. This article reviews recent evidence for sex differences in dyslexia, discusses the impact these studies have on the understanding of the brain basis of dyslexia, and provides a framework for how these differential neuroanatomical profiles may develop.
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Affiliation(s)
- Anthony J Krafnick
- Psychology Department, Dominican University, River Forest, IL, United States
| | - Tanya M Evans
- Center for Advanced Study of Teaching and Learning, Curry School of Education and Human Development, University of Virginia, Charlottesville, VA, United States
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8
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Müller B, Boltze J, Czepezauer I, Hesse V, Wilcke A, Kirsten H. Dyslexia risk variant rs600753 is linked with dyslexia-specific differential allelic expression of DYX1C1. Genet Mol Biol 2018; 41:41-49. [PMID: 29473935 PMCID: PMC5901500 DOI: 10.1590/1678-4685-gmb-2017-0165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/28/2017] [Indexed: 11/22/2022] Open
Abstract
An increasing number of genetic variants involved in dyslexia development were
discovered during the last years, yet little is known about the molecular
functional mechanisms of these SNPs. In this study we investigated whether
dyslexia candidate SNPs have a direct, disease-specific effect on local
expression levels of the assumed target gene by using a differential allelic
expression assay. In total, 12 SNPs previously associated with dyslexia and
related phenotypes were suitable for analysis. Transcripts corresponding to four
SNPs were sufficiently expressed in 28 cell lines originating from controls and
a family affected by dyslexia. We observed a significant effect of rs600753 on
expression levels of DYX1C1 in forward and reverse sequencing
approaches. The expression level of the rs600753 risk allele was increased in
the respective seven cell lines from members of the dyslexia family which might
be due to a disturbed transcription factor binding sites. When considering our
results in the context of neuroanatomical dyslexia-specific findings, we
speculate that this mechanism may be part of the pathomechanisms underlying the
dyslexia-specific brain phenotype. Our results suggest that allele-specific
DYX1C1 expression levels depend on genetic variants of
rs600753 and contribute to dyslexia. However, these results are preliminary and
need replication.
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Affiliation(s)
- Bent Müller
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany
| | - Johannes Boltze
- Fraunhofer Research Institution for Marine Biotechnology, Department of Medical Cell Technology, Lübeck, Germany.,Institute for Medical and Marine Biotechnology, University of Lübeck, Lübeck, Germany
| | - Ivonne Czepezauer
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany
| | - Volker Hesse
- German Center for Growth, Development and Health Encouragement in Childhood and Adolescence, Berlin, Germany.,Charité-University Medicine Berlin, Institute for Experimental Paediatric Endocrinolgy, Berlin
| | | | - Arndt Wilcke
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany
| | - Holger Kirsten
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany.,Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig, Leipzig, Germany.,LIFE - Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany
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9
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Abbott RD, Raskind WH, Matsushita M, Price ND, Richards T, Berninger VW. Patterns of biomarkers for three phenotype profiles of persisting specific learning disabilities during middle childhood and early adolescence: A preliminary study. BIOMARKERS AND GENES 2017; 1:103. [PMID: 30854516 PMCID: PMC6407889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Students without specific learning disabilities [SLDs] [n=18] and with one of three persisting SLDs in written language despite early and current specialized instruction-Dysgraphia [n=21], Dyslexia [n=40], or oral and written language learning disability OWL LD [n=14]- in grades 4 to 9 [N=56 boys, 38 girls] completed behavioral phenotyping assessment and gave a small blood or saliva sample. Molecular analyses informed by current cross-site research on gene candidates for learning disabilities identified associations between molecular genetic markers and the two defining behavioral phenotypes for each SLDs-WL; dysgraphia [impaired writing alphabet from memory for rs3743204 and sentence copying in best handwriting for rs79382 both in DYX1C1], dyslexia [impaired silent word reading/decoding rate for rs4535189 in DCDC2 and impaired spelling/encoding for rs374205 in DYX1C1], and OWL LD [impaired aural syntax comprehension for rs807701 and oral syntax construction for rs807701 both in DYX1C1]. Implications of these identified associations between molecular markers for alleles for different sites within two gene candidates [and mostly one] and hallmark phenotypes are discussed for translation science [application to practice] and neuroimaging that has identified contrasting brain bases for each of the three SLDs.
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Affiliation(s)
- Robert D. Abbott
- University of Washington, Quantitative Studies and Measurement, USA
| | - Wendy H. Raskind
- University of Washington, Medicine, USA,University of Washington, Psychiatry and Behavioral Sciences, USA
| | | | - Nathan D. Price
- Institute for Systems Biology, USA,University of Washington, Bioengineering, Computer Science & Engineering, Molecular & Cellular Biology, USA
| | - Todd Richards
- University of Washington, Integrated Brain Imaging Center and Radiology, USA
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Schenkel LC, Rodenhiser D, Siu V, McCready E, Ainsworth P, Sadikovic B. Constitutional Epi/Genetic Conditions: Genetic, Epigenetic, and Environmental Factors. J Pediatr Genet 2017; 6:30-41. [PMID: 28180025 PMCID: PMC5288004 DOI: 10.1055/s-0036-1593849] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 04/14/2016] [Indexed: 12/12/2022]
Abstract
There are more than 4,000 phenotypes for which the molecular basis is at least partly known. Though defects in primary DNA structure constitute a major cause of these disorders, epigenetic disruption is emerging as an important alternative mechanism in the etiology of a broad range of congenital and developmental conditions. These include epigenetic defects caused by either localized (in cis) genetic alterations or more distant (in trans) genetic events but can also include environmental effects. Emerging evidence suggests interplay between genetic and environmental factors in the epigenetic etiology of several constitutional "epi/genetic" conditions. This review summarizes our broadening understanding of how epigenetics contributes to pediatric disease by exploring different classes of epigenomic disorders. It further challenges the simplistic dogma of "DNA encodes RNA encodes protein" to best understand the spectrum of factors that can influence genetic traits in a pediatric population.
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Affiliation(s)
- Laila C. Schenkel
- Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada
- Children's Health Research Institute, London, Ontario, Canada
| | - David Rodenhiser
- Children's Health Research Institute, London, Ontario, Canada
- Department of Biochemistry, Western University, London, Ontario, Canada
- Department of Pediatrics, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
- Department of Oncology, Western University, London, Ontario, Canada
| | - Victoria Siu
- Children's Health Research Institute, London, Ontario, Canada
- Department of Pediatrics, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
| | - Elizabeth McCready
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Peter Ainsworth
- Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada
- Children's Health Research Institute, London, Ontario, Canada
- Department of Biochemistry, Western University, London, Ontario, Canada
- Department of Pediatrics, Western University, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
- Department of Oncology, Western University, London, Ontario, Canada
| | - Bekim Sadikovic
- Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada
- Children's Health Research Institute, London, Ontario, Canada
- London Regional Cancer Program, London Health Sciences Centre, London, Ontario, Canada
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11
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Genes, Gender, Environment, and Novel Functions of Estrogen Receptor Beta in the Susceptibility to Neurodevelopmental Disorders. Brain Sci 2017; 7:brainsci7030024. [PMID: 28241485 PMCID: PMC5366823 DOI: 10.3390/brainsci7030024] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 02/14/2017] [Accepted: 02/17/2017] [Indexed: 12/30/2022] Open
Abstract
Many neurological disorders affect men and women differently regarding prevalence, progression, and severity. It is clear that many of these disorders may originate from defective signaling during fetal or perinatal brain development, which may affect males and females differently. Such sex-specific differences may originate from chromosomal or sex-hormone specific effects. This short review will focus on the estrogen receptor beta (ERβ) signaling during perinatal brain development and put it in the context of sex-specific differences in neurodevelopmental disorders. We will discuss ERβ’s recent discovery in directing DNA de-methylation to specific sites, of which one such site may bear consequences for the susceptibility to the neurological reading disorder dyslexia. We will also discuss how dysregulations in sex-hormone signaling, like those evoked by endocrine disruptive chemicals, may affect this and other neurodevelopmental disorders in a sex-specific manner through ERβ.
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12
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Kong R, Song RR. [Research advances in susceptible genes for developmental dyslexia in children]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2016; 18:1308-1312. [PMID: 27974128 PMCID: PMC7403085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 08/24/2016] [Indexed: 12/16/2023]
Abstract
Developmental dyslexia in children is one of the neurodevelopmental disorders and is affected by various susceptible genes. In recent years, researchers have found some susceptible genes for dyslexia via chromosome analysis, genome-wide association studies, association analysis, gene function research, neuroimaging, and neurophysiological techniques. This article reviews the research advances in susceptible genes for developmental dyslexia, and with the study on susceptible genes for dyslexia, it lays a foundation for in-depth studies on the "gene-brain-behavior" level and provides scientific clues for exploring etiology and pathogenesis of dyslexia.
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Affiliation(s)
- Rui Kong
- Department of Maternal and Child Health Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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Kong R, Song RR. [Research advances in susceptible genes for developmental dyslexia in children]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2016; 18:1308-1312. [PMID: 27974128 PMCID: PMC7403085 DOI: 10.7499/j.issn.1008-8830.2016.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 08/24/2016] [Indexed: 06/06/2023]
Abstract
Developmental dyslexia in children is one of the neurodevelopmental disorders and is affected by various susceptible genes. In recent years, researchers have found some susceptible genes for dyslexia via chromosome analysis, genome-wide association studies, association analysis, gene function research, neuroimaging, and neurophysiological techniques. This article reviews the research advances in susceptible genes for developmental dyslexia, and with the study on susceptible genes for dyslexia, it lays a foundation for in-depth studies on the "gene-brain-behavior" level and provides scientific clues for exploring etiology and pathogenesis of dyslexia.
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Affiliation(s)
- Rui Kong
- Department of Maternal and Child Health Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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Tammimies K, Bieder A, Lauter G, Sugiaman-Trapman D, Torchet R, Hokkanen ME, Burghoorn J, Castrén E, Kere J, Tapia-Páez I, Swoboda P. Ciliary dyslexia candidate genes DYX1C1 and DCDC2 are regulated by Regulatory Factor X (RFX) transcription factors through X-box promoter motifs. FASEB J 2016; 30:3578-3587. [PMID: 27451412 PMCID: PMC5024701 DOI: 10.1096/fj.201500124rr] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 07/05/2016] [Indexed: 11/11/2022]
Abstract
DYX1C1, DCDC2, and KIAA0319 are
three of the most replicated dyslexia candidate genes (DCGs). Recently, these DCGs
were implicated in functions at the cilium. Here, we investigate the regulation of
these DCGs by Regulatory Factor X transcription factors (RFX TFs), a gene family
known for transcriptionally regulating ciliary genes. We identify conserved X-box
motifs in the promoter regions of DYX1C1, DCDC2, and
KIAA0319 and demonstrate their functionality, as well as the
ability to recruit RFX TFs using reporter gene and electrophoretic mobility shift
assays. Furthermore, we uncover a complex regulation pattern between
RFX1, RFX2, and RFX3 and their
significant effect on modifying the endogenous expression of DYX1C1
and DCDC2 in a human retinal pigmented epithelial cell line
immortalized with hTERT (hTERT-RPE1). In addition, induction of ciliogenesis
increases the expression of RFX TFs and DCGs. At the protein level, we show that
endogenous DYX1C1 localizes to the base of the cilium, whereas DCDC2 localizes along
the entire axoneme of the cilium, thereby validating earlier localization studies
using overexpression models. Our results corroborate the emerging role of DCGs in
ciliary function and characterize functional noncoding elements, X-box promoter
motifs, in DCG promoter regions, which thus can be targeted for mutation screening in
dyslexia and ciliopathies associated with these genes.—Tammimies, K., Bieder,
A., Lauter, G., Sugiaman-Trapman, D., Torchet, R., Hokkanen, M.-E., Burghoorn, J.,
Castrén, E., Kere, J., Tapia-Páez, I., Swoboda, P. Ciliary dyslexia
candidate genes DYX1C1 and DCDC2 are regulated by
Regulatory Factor (RF) X transcription factors through X-box promoter motifs.
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Affiliation(s)
- Kristiina Tammimies
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden; Center of Neurodevelopmental Disorders (KIND), Pediatric Neuropsychiatry Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Bieder
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Gilbert Lauter
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | | | - Rachel Torchet
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | | | - Jan Burghoorn
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Eero Castrén
- Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Juha Kere
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden; Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland; and Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Isabel Tapia-Páez
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden;
| | - Peter Swoboda
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden;
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Zettergren A, Karlsson S, Hovey D, Jonsson L, Melke J, Anckarsäter H, Lichtenstein P, Lundström S, Westberg L. Further investigations of the relation between polymorphisms in sex steroid related genes and autistic-like traits. Psychoneuroendocrinology 2016; 68:1-5. [PMID: 26930261 DOI: 10.1016/j.psyneuen.2016.02.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 02/19/2016] [Accepted: 02/19/2016] [Indexed: 11/15/2022]
Abstract
Autism spectrum disorders (ASDs) are more prevalent in boys than in girls, indicating that high levels of testosterone during early development may be a risk factor. Evidence for this hypothesis comes from studies showing associations between fetal testosterone levels, as well as indirect measures of prenatal androgenization, and ASDs and autistic-like traits (ALTs). In a recent study we reported associations between ALTs and single nucleotide polymorphisms (SNPs) in the genes encoding estrogen receptor 1 (ESR1), steroid-5-alpha-reductase, type 2 (SRD5A2) and sex hormone-binding globulin (SHBG) in a subset (n=1771) from the Child and Adolescent Twin Study in Sweden (CATSS). The aim of the present study was to try to replicate these findings in an additional, larger, sample of individuals from the CATSS (n=10,654), as well as to analyze additional SNPs of functional importance in SHBG and SRD5A2. No associations between the previously associated SNPs in the genes ESR1 and SRD5A2 and ALTs could be seen in the large replication sample. Still, our results show that two non-linked SNPs (rs6259 and rs9901675) at the SHBG gene locus might be of importance for language impairment problems in boys. The results of the present study do not point toward a major role for the investigated SNPs in the genes ESR1 and SRD5A2 in ALTs, but a possible influence of genetic variation in SHBG, especially for language impairment problems in boys, cannot be ruled out.
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Affiliation(s)
- Anna Zettergren
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden; Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, University of Gothenburg, Sweden.
| | - Sara Karlsson
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden
| | - Daniel Hovey
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden
| | - Lina Jonsson
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden
| | - Jonas Melke
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden
| | - Henrik Anckarsäter
- Institute of Neuroscience and Physiology, Centre of Ethics, Law and Mental Health (CELAM), University of Gothenburg, Sweden
| | - Paul Lichtenstein
- Karolinska Institutet, Department of Medical Epidemiology and Biostatistics, Stockholm, Sweden
| | - Sebastian Lundström
- Institute of Neuroscience and Physiology, Centre of Ethics, Law and Mental Health (CELAM), University of Gothenburg, Sweden; Institute of Neuroscience and Physiology, Gillberg Neuropsychiatry Centre, University of Gothenburg, Sweden
| | - Lars Westberg
- Institute of Neuroscience and Physiology, Department of Pharmacology, University of Gothenburg, Sweden
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Schenkel LC, Rodenhiser DI, Ainsworth PJ, Paré G, Sadikovic B. DNA methylation analysis in constitutional disorders: Clinical implications of the epigenome. Crit Rev Clin Lab Sci 2016; 53:147-65. [PMID: 26758403 DOI: 10.3109/10408363.2015.1113496] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Genomic, chromosomal, and gene-specific changes in the DNA sequence underpin both phenotypic variations in populations as well as disease associations, and the application of genomic technologies for the identification of constitutional (inherited) or somatic (acquired) alterations in DNA sequence forms a cornerstone of clinical and molecular genetics. In addition to the disruption of primary DNA sequence, the modulation of DNA function by epigenetic phenomena, in particular by DNA methylation, has long been known to play a role in the regulation of gene expression and consequent pathogenesis. However, these epigenetic factors have been identified only in a handful of pediatric conditions, including imprinting disorders. Technological advances in the past decade that have revolutionized clinical genomics are now rapidly being applied to the emerging discipline of clinical epigenomics. Here, we present an overview of epigenetic mechanisms with a focus on DNA modifications, including the molecular mechanisms of DNA methylation and subtypes of DNA modifications, and we describe the classic and emerging genomic technologies that are being applied to this study. This review focuses primarily on constitutional epigenomic conditions associated with a spectrum of developmental and intellectual disabilities. Epigenomic disorders are discussed in the context of global genomic disorders, imprinting disorders, and single gene disorders. We include a section focused on integration of genetic and epigenetic mechanisms together with their effect on clinical phenotypes. Finally, we summarize emerging epigenomic technologies and their impact on diagnostic aspects of constitutional genetic and epigenetic disorders.
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Affiliation(s)
| | - David I Rodenhiser
- b Departments of Biochemistry , Oncology and Paediatrics, Western University , London , ON , Canada .,c London Regional Cancer Program, London Health Sciences Centre , London , ON , Canada .,e Children's Health Research Institute , London , ON , Canada
| | - Peter J Ainsworth
- a Departments of Pathology and Laboratory Medicine .,b Departments of Biochemistry , Oncology and Paediatrics, Western University , London , ON , Canada .,c London Regional Cancer Program, London Health Sciences Centre , London , ON , Canada .,d Molecular Genetics Laboratory, London Health Sciences Centre , London , ON , Canada .,e Children's Health Research Institute , London , ON , Canada
| | - Guillaume Paré
- f Department of Pathology and Molecular Medicine , and.,g Department of Clinical Epidemiology and Biostatistics , McMaster University , Hamilton , ON , Canada
| | - Bekim Sadikovic
- a Departments of Pathology and Laboratory Medicine .,c London Regional Cancer Program, London Health Sciences Centre , London , ON , Canada .,d Molecular Genetics Laboratory, London Health Sciences Centre , London , ON , Canada .,e Children's Health Research Institute , London , ON , Canada
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Nalvarte I, Töhönen V, Lindeberg M, Varshney M, Gustafsson JÅ, Inzunza J. Estrogen receptor β controls MMP-19 expression in mouse ovaries during ovulation. Reproduction 2015; 151:253-9. [PMID: 26700939 DOI: 10.1530/rep-15-0522] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 12/22/2015] [Indexed: 02/06/2023]
Abstract
Estrogen receptor beta (ERβ/ESR2) has a central role in mouse ovaries, as ERβ knockout (BERKO) mice are subfertile due to an increase in fibrosis around the maturing follicle and a decrease in blood supply. This has a consequence that these follicles rarely rupture to release the mature oocyte. Matrix metalloproteinases (MMPs) are modulators of the extracellular matrix, and the expression of one specific MMP, MMP-19, is normally increased in granulosa cells during their maturation until ovulation. In this study, we demonstrate that MMP-19 levels are downregulated in BERKO mouse ovaries. Using human MCF-7 cells that overexpress ERβ, we could identify MMP-19 to be a transcriptional target of ligand-bound activated ERβ acting on a specificity protein-1 binding site. These data provide a molecular explanation for the observed follicle rupture defect that contributes to the subfertility of female BERKO mice.
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Affiliation(s)
- Ivan Nalvarte
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
| | - Virpi Töhönen
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
| | - Maria Lindeberg
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
| | - Mukesh Varshney
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
| | - Jan-Åke Gustafsson
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
| | - José Inzunza
- Department of Biosciences and NutritionKarolinska Institutet, SE-14183 Huddinge, SwedenCenter for Nuclear Receptors and SignalingUniversity of Houston, Houston, Texas 77204-5056, USA
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Gialluisi A, Newbury DF, Wilcutt EG, Olson RK, DeFries JC, Brandler WM, Pennington BF, Smith SD, Scerri TS, Simpson NH, Luciano M, Evans DM, Bates TC, Stein JF, Talcott JB, Monaco AP, Paracchini S, Francks C, Fisher SE. Genome-wide screening for DNA variants associated with reading and language traits. GENES BRAIN AND BEHAVIOR 2014; 13:686-701. [PMID: 25065397 PMCID: PMC4165772 DOI: 10.1111/gbb.12158] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/20/2014] [Accepted: 07/24/2014] [Indexed: 01/04/2023]
Abstract
Reading and language abilities are heritable traits that are likely to share some genetic influences with each other. To identify pleiotropic genetic variants affecting these traits, we first performed a genome-wide association scan (GWAS) meta-analysis using three richly characterized datasets comprising individuals with histories of reading or language problems, and their siblings. GWAS was performed in a total of 1862 participants using the first principal component computed from several quantitative measures of reading- and language-related abilities, both before and after adjustment for performance IQ. We identified novel suggestive associations at the SNPs rs59197085 and rs5995177 (uncorrected P ≈ 10–7 for each SNP), located respectively at the CCDC136/FLNC and RBFOX2 genes. Each of these SNPs then showed evidence for effects across multiple reading and language traits in univariate association testing against the individual traits. FLNC encodes a structural protein involved in cytoskeleton remodelling, while RBFOX2 is an important regulator of alternative splicing in neurons. The CCDC136/FLNC locus showed association with a comparable reading/language measure in an independent sample of 6434 participants from the general population, although involving distinct alleles of the associated SNP. Our datasets will form an important part of on-going international efforts to identify genes contributing to reading and language skills.
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Affiliation(s)
- A Gialluisi
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
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Eicher JD, Gruen JR. Imaging-genetics in dyslexia: connecting risk genetic variants to brain neuroimaging and ultimately to reading impairments. Mol Genet Metab 2013; 110:201-12. [PMID: 23916419 PMCID: PMC3800223 DOI: 10.1016/j.ymgme.2013.07.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 07/02/2013] [Accepted: 07/02/2013] [Indexed: 12/19/2022]
Abstract
Dyslexia is a common pediatric disorder that affects 5-17% of schoolchildren in the United States. It is marked by unexpected difficulties in fluent reading despite adequate intelligence, opportunity, and instruction. Classically, neuropsychologists have studied dyslexia using a variety of neurocognitive batteries to gain insight into the specific deficits and impairments in affected children. Since dyslexia is a complex genetic trait with high heritability, analyses conditioned on performance on these neurocognitive batteries have been used to try to identify associated genes. This has led to some successes in identifying contributing genes, although much of the heritability remains unexplained. Additionally, the lack of relevant human brain tissue for analysis and the challenges of modeling a uniquely human trait in animals are barriers to advancing our knowledge of the underlying pathophysiology. In vivo imaging technologies, however, present new opportunities to examine dyslexia and reading skills in a clearly relevant context in human subjects. Recent investigations have started to integrate these imaging data with genetic data in attempts to gain a more complete and complex understanding of reading processes. In addition to bridging the gap from genetic risk variant to a discernible neuroimaging phenotype and ultimately to the clinical impairments in reading performance, the use of neuroimaging phenotypes will reveal novel risk genes and variants. In this article, we briefly discuss the genetic and imaging investigations and take an in-depth look at the recent imaging-genetics investigations of dyslexia.
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Affiliation(s)
- John D. Eicher
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520
| | - Jeffrey R. Gruen
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520
- Departments of Pediatrics and Investigative Medicine, Yale University School of Medicine, New Haven, CT 06520
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Adler WT, Platt MP, Mehlhorn AJ, Haight JL, Currier TA, Etchegaray MA, Galaburda AM, Rosen GD. Position of neocortical neurons transfected at different gestational ages with shRNA targeted against candidate dyslexia susceptibility genes. PLoS One 2013; 8:e65179. [PMID: 23724130 PMCID: PMC3665803 DOI: 10.1371/journal.pone.0065179] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/24/2013] [Indexed: 01/12/2023] Open
Abstract
Developmental dyslexia is a language learning disorder that affects approximately 4–10% of the population. A number of candidate dyslexia susceptibility genes have been identified, including DCDC2 and KIAA0319 on Chromosome (Chr) 6p22.2 and DYX1C1 on Chr 15q21. Embryonic knockdown of the function of homologs of these genes in rat neocortical projection cell progenitors by in utero electroporation of plasmids encoding small hairpin RNA (shRNA) revealed that all three genes disrupted neuronal migration to the neocortex. Specifically, this disruption would result in heterotopia formation (Dyx1c1 and Kiaa0319) and/or overmigration past their expected laminar location (Dyx1c1 and Dcdc2). In these experiments, neurons normally destined for the upper neocortical laminæ were transfected on embryonic day (E) 15.5, and we designed experiments to test whether these migration phenotypes were the result of targeting a specific type of projection neuron. We transfected litters with Dcdc2 shRNA, Dyx1c1 shRNA, Kiaa0319 shRNA, or fluorescent protein (as a control) at each of three gestational ages (E14.5, E15.5, or E16.5). Pups were allowed to come to term, and their brains were examined at 3 weeks of age for the position of transfected cells. We found that age of transfection did not affect the percentage of unmigrated neurons—transfection with Kiaa0319 shRNA resulted in heterotopia formation at all three ages. Overmigration of neurons transfected with Dcdc2 shRNA, while present following transfections at the later ages, did not occur following E14.5 transfections. These results are considered in light of the known functions of each of these candidate dyslexia susceptibility genes.
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Affiliation(s)
- William T. Adler
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Maryann P. Platt
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Alison J. Mehlhorn
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Joshua L. Haight
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Timothy A. Currier
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Mikel A. Etchegaray
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Albert M. Galaburda
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Glenn D. Rosen
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
- * E-mail:
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Raskind WH, Peter B, Richards T, Eckert MM, Berninger VW. The genetics of reading disabilities: from phenotypes to candidate genes. Front Psychol 2013; 3:601. [PMID: 23308072 PMCID: PMC3538356 DOI: 10.3389/fpsyg.2012.00601] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/18/2012] [Indexed: 12/19/2022] Open
Abstract
This article provides an overview of (a) issues in definition and diagnosis of specific reading disabilities at the behavioral level that may occur in different constellations of developmental and phenotypic profiles (patterns); (b) rapidly expanding research on genetic heterogeneity and gene candidates for dyslexia and other reading disabilities; (c) emerging research on gene-brain relationships; and (d) current understanding of epigenetic mechanisms whereby environmental events may alter behavioral expression of genetic variations. A glossary of genetic terms (denoted by bold font) is provided for readers not familiar with the technical terms.
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Affiliation(s)
- Wendy H Raskind
- Department of Medicine, University of Washington Seattle, WA, USA ; Department of Psychiatry and Behavioral Sciences, University of Washington Seattle, WA, USA
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