The Experts below are selected from a list of 345 Experts worldwide ranked by ideXlab platform
Kristina Moll - One of the best experts on this subject based on the ideXlab platform.
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Genome-wide association study reveals new insights into the heritability and genetic correlates of developmental dyslexia
Molecular Psychiatry, 2020Co-Authors: Alessandro Gialluisi, Kristina Moll, Till F. M. Andlauer, Nazanin Mirza-schreiber, Jessica Becker, Per Hoffmann, Kerstin U. Ludwig, Darina Czamara, Beate St Pourcain, Ferenc HonbolygóAbstract:Developmental dyslexia (DD) is a Learning Disorder affecting the ability to read, with a heritability of 40–60%. A notable part of this heritability remains unexplained, and large genetic studies are warranted to identify new susceptibility genes and clarify the genetic bases of dyslexia. We carried out a genome-wide association study (GWAS) on 2274 dyslexia cases and 6272 controls, testing associations at the single variant, gene, and pathway level, and estimating heritability using single-nucleotide polymorphism (SNP) data. We also calculated polygenic scores (PGSs) based on large-scale GWAS data for different neuropsychiatric Disorders and cortical brain measures, educational attainment, and fluid intelligence, testing them for association with dyslexia status in our sample. We observed statistically significant ( p
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cognitive risk factors for specific Learning Disorder processing speed temporal processing and working memory
Journal of Learning Disabilities, 2016Co-Authors: Kristina Moll, Silke M Gobel, Debbie Gooch, Karin Landerl, Margaret J SnowlingAbstract:High comorbidity rates between reading Disorder (RD) and mathematics Disorder (MD) indicate that, although the cognitive core deficits underlying these Disorders are distinct, additional domain-general risk factors might be shared between the Disorders. Three domain-general cognitive abilities were investigated in children with RD and MD: processing speed, temporal processing, and working memory. Since attention problems frequently co-occur with Learning Disorders, the study examined whether these three factors, which are known to be associated with attention problems, account for the comorbidity between these Disorders. The sample comprised 99 primary school children in four groups: children with RD, children with MD, children with both Disorders (RD+MD), and typically developing children (TD controls). Measures of processing speed, temporal processing, and memory were analyzed in a series of ANCOVAs including attention ratings as covariate. All three risk factors were associated with poor attention. After controlling for attention, associations with RD and MD differed: Although deficits in verbal memory were associated with both RD and MD, reduced processing speed was related to RD, but not MD; and the association with RD was restricted to processing speed for familiar nameable symbols. In contrast, impairments in temporal processing and visuospatial memory were associated with MD, but not RD.
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specific Learning Disorder prevalence and gender differences
PLOS ONE, 2014Co-Authors: Kristina Moll, Sarah Kunze, Nina Neuhoff, Jennifer Bruder, Gerd SchultekorneAbstract:Comprehensive models of Learning Disorders have to consider both isolated Learning Disorders that affect one Learning domain only, as well as comorbidity between Learning Disorders. However, empirical evidence on comorbidity rates including all three Learning Disorders as defined by DSM-5 (deficits in reading, writing, and mathematics) is scarce. The current study assessed prevalence rates and gender ratios for isolated as well as comorbid Learning Disorders in a representative sample of 1633 German speaking children in 3rd and 4th Grade. Prevalence rates were analysed for isolated as well as combined Learning Disorders and for different deficit criteria, including a criterion for normal performance. Comorbid Learning Disorders occurred as frequently as isolated Learning Disorders, even when stricter cutoff criteria were applied. The relative proportion of isolated and combined Disorders did not change when including a criterion for normal performance. Reading and spelling deficits differed with respect to their association with arithmetic problems: Deficits in arithmetic co-occurred more often with deficits in spelling than with deficits in reading. In addition, comorbidity rates for arithmetic and reading decreased when applying stricter deficit criteria, but stayed high for arithmetic and spelling irrespective of the chosen deficit criterion. These findings suggest that the processes underlying the relationship between arithmetic and reading might differ from those underlying the relationship between arithmetic and spelling. With respect to gender ratios, more boys than girls showed spelling deficits, while more girls were impaired in arithmetic. No gender differences were observed for isolated reading problems and for the combination of all three Learning Disorders. Implications of these findings for assessment and intervention of Learning Disorders are discussed.
Anca Dragomir - One of the best experts on this subject based on the ideXlab platform.
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rare variants in dynein heavy chain genes in two individuals with situs inversus and developmental dyslexia a case report
BMC Medical Genetics, 2020Co-Authors: Andrea Bieder, Elisabet Einarsdottir, Hans Matsson, Harriet Nilsson, Jesper Eisfeldt, Anca DragomirAbstract:Developmental dyslexia (DD) is a neurodevelopmental Learning Disorder with high heritability. A number of candidate susceptibility genes have been identified, some of which are linked to the function of the cilium, an organelle regulating left-right asymmetry development in the embryo. Furthermore, it has been suggested that disrupted left-right asymmetry of the brain may play a role in neurodevelopmental Disorders such as DD. However, it is unknown whether there is a common genetic cause to DD and laterality defects or ciliopathies. Here, we studied two individuals with co-occurring situs inversus (SI) and DD using whole genome sequencing to identify genetic variants of importance for DD and SI. Individual 1 had primary ciliary dyskinesia (PCD), a rare, autosomal recessive Disorder with oto-sino-pulmonary phenotype and SI. We identified two rare nonsynonymous variants in the dynein axonemal heavy chain 5 gene (DNAH5): a previously reported variant c.7502G > C; p.(R2501P), and a novel variant c.12043 T > G; p.(Y4015D). Both variants are predicted to be damaging. Ultrastructural analysis of the cilia revealed a lack of outer dynein arms and normal inner dynein arms. MRI of the brain revealed no significant abnormalities. Individual 2 had non-syndromic SI and DD. In individual 2, one rare variant (c.9110A > G;p.(H3037R)) in the dynein axonemal heavy chain 11 gene (DNAH11), coding for another component of the outer dynein arm, was identified. We identified the likely genetic cause of SI and PCD in one individual, and a possibly significant heterozygosity in the other, both involving dynein genes. Given the present evidence, it is unclear if the identified variants also predispose to DD and further studies into the association between laterality, ciliopathies and DD are needed.
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rare variants in dynein heavy chain genes in two individuals with situs inversus and developmental dyslexia
bioRxiv, 2020Co-Authors: Andrea Bieder, Elisabet Einarsdottir, Hans Matsson, Harriet Nilsson, Jesper Eisfeldt, Anca Dragomir, Martin Paucar, Tobias Granberg, Anna Lindstrand, Juha KereAbstract:Background: Developmental dyslexia (DD) is a neurodevelopmental Learning Disorder with high heritability. A number of candidate susceptibility genes have been identified, some of which are linked to the function of the cilium, an organelle regulating left-right asymmetry development in the embryo. Furthermore, it has been suggested that disrupted left-right asymmetry of the brain may play a role in neurodevelopmental Disorders such as DD. Methods: Here, we studied two individuals with co-occurring situs inversus (SI) and DD using whole genome sequencing to identify single nucleotide variants or copy number variations of importance for DD and SI. Results: Individual 1 had primary ciliary dyskinesia (PCD), a rare, autosomal recessive Disorder with oto-sino-pulmonary phenotype and SI. We identified two rare nonsynonymous variants in the dynein axonemal heavy chain 5 gene (DNAH5): c.7502G>C;p.(R2501P), a previously reported variant predicted to be damaging and c.12043T>G;p.(Y4015D), a novel variant predicted to be damaging. Ultrastructural analysis of the cilia revealed a lack of outer dynein arms and normal inner dynein arms. MRI of the brain revealed no significant abnormalities. Individual 2 had non-syndromic SI and DD. In individual 2, one rare variant (c.9110A>G;p.(H3037R)) in the dynein axonemal heavy chain 11 gene (DNAH11), coding for another component of the outer dynein arm, was identified. Conclusions: We identified the likely genetic cause of SI and PCD in one individual, and a possibly significant heterozygosity in the other, both involving dynein genes. Given the present evidence, it is unclear if the identified variants also predispose to DD, but further studies into the association are warranted.
Cesare Cornoldi - One of the best experts on this subject based on the ideXlab platform.
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strengths and weaknesses in the intellectual profile of different subtypes of specific Learning Disorder a study on 1 049 diagnosed children
Clinical psychological science, 2017Co-Authors: Enrico Toffalini, David Giofre, Cesare CornoldiAbstract:The present study analyzes whether and how the most common diagnoses within the specific Learning Disorder (SLD) category are characterized by different intellectual profiles. The issue is relevant...
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forward and backward digit span difficulties in children with specific Learning Disorder
Journal of Clinical and Experimental Neuropsychology, 2016Co-Authors: David Giofre, Ernesto Stoppa, Paolo Ferioli, Lina Pezzuti, Cesare CornoldiAbstract:ABSTRACTThis study examined performance in the forward and backward digit span task of the Wechsler Intelligence Scale for Children–Fourth Edition (WISC–IV) in a large group of children with specific Learning Disorder (SLD) as compared with a group of typically developing children matched for age and sex. Our results further support the hypothesis that the intellectual difficulties of children with SLD involve working memory in the forward digit span task to a greater extent than in the backward digit span task. The correlation of the two spans with a General Ability Index (GAI) was similar in SLD, and smaller in magnitude than in typically developing children. Despite a GAI within normal range, children with SLD had difficulty with both digit span tasks, but more so for forward span. This pattern was similar for different SLD profiles with clinical diagnoses of dyslexia and mixed Disorder, but the impairments were more severe in the latter. Age differences were also investigated, demonstrating larger spa...
Juha Kere - One of the best experts on this subject based on the ideXlab platform.
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rare variants in dynein heavy chain genes in two individuals with situs inversus and developmental dyslexia
bioRxiv, 2020Co-Authors: Andrea Bieder, Elisabet Einarsdottir, Hans Matsson, Harriet Nilsson, Jesper Eisfeldt, Anca Dragomir, Martin Paucar, Tobias Granberg, Anna Lindstrand, Juha KereAbstract:Background: Developmental dyslexia (DD) is a neurodevelopmental Learning Disorder with high heritability. A number of candidate susceptibility genes have been identified, some of which are linked to the function of the cilium, an organelle regulating left-right asymmetry development in the embryo. Furthermore, it has been suggested that disrupted left-right asymmetry of the brain may play a role in neurodevelopmental Disorders such as DD. Methods: Here, we studied two individuals with co-occurring situs inversus (SI) and DD using whole genome sequencing to identify single nucleotide variants or copy number variations of importance for DD and SI. Results: Individual 1 had primary ciliary dyskinesia (PCD), a rare, autosomal recessive Disorder with oto-sino-pulmonary phenotype and SI. We identified two rare nonsynonymous variants in the dynein axonemal heavy chain 5 gene (DNAH5): c.7502G>C;p.(R2501P), a previously reported variant predicted to be damaging and c.12043T>G;p.(Y4015D), a novel variant predicted to be damaging. Ultrastructural analysis of the cilia revealed a lack of outer dynein arms and normal inner dynein arms. MRI of the brain revealed no significant abnormalities. Individual 2 had non-syndromic SI and DD. In individual 2, one rare variant (c.9110A>G;p.(H3037R)) in the dynein axonemal heavy chain 11 gene (DNAH11), coding for another component of the outer dynein arm, was identified. Conclusions: We identified the likely genetic cause of SI and PCD in one individual, and a possibly significant heterozygosity in the other, both involving dynein genes. Given the present evidence, it is unclear if the identified variants also predispose to DD, but further studies into the association are warranted.
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the axon guidance receptor gene robo1 is a candidate gene for developmental dyslexia
PLOS Genetics, 2005Co-Authors: Katariina Hannulajouppi, Nina Kaminenahola, Mikko Taipale, Ranja Eklund, Jaana Nopolahemmi, Helena Kaariainen, Juha KereAbstract:Dyslexia, or specific reading disability, is the most common Learning Disorder with a complex, partially genetic basis, but its biochemical mechanisms remain poorly understood. A locus on Chromosome 3, DYX5, has been linked to dyslexia in one large family and speech-sound Disorder in a subset of small families. We found that the axon guidance receptor gene ROBO1, orthologous to the Drosophila roundabout gene, is disrupted by a chromosome translocation in a dyslexic individual. In a large pedigree with 21 dyslexic individuals genetically linked to a specific haplotype of ROBO1 (not found in any other chromosomes in our samples), the expression of ROBO1 from this haplotype was absent or attenuated in affected individuals. Sequencing of ROBO1 in apes revealed multiple coding differences, and the selection pressure was significantly different between the human, chimpanzee, and gorilla branch as compared to orangutan. We also identified novel exons and splice variants of ROBO1 that may explain the apparent phenotypic differences between human and mouse in heterozygous loss of ROBO1. We conclude that dyslexia may be caused by partial haplo-insufficiency for ROBO1 in rare families. Thus, our data suggest that a slight disturbance in neuronal axon crossing across the midline between brain hemispheres, dendrite guidance, or another function of ROBO1 may manifest as a specific reading disability in humans.
Gerd Schultekorne - One of the best experts on this subject based on the ideXlab platform.
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specific Learning Disorder prevalence and gender differences
PLOS ONE, 2014Co-Authors: Kristina Moll, Sarah Kunze, Nina Neuhoff, Jennifer Bruder, Gerd SchultekorneAbstract:Comprehensive models of Learning Disorders have to consider both isolated Learning Disorders that affect one Learning domain only, as well as comorbidity between Learning Disorders. However, empirical evidence on comorbidity rates including all three Learning Disorders as defined by DSM-5 (deficits in reading, writing, and mathematics) is scarce. The current study assessed prevalence rates and gender ratios for isolated as well as comorbid Learning Disorders in a representative sample of 1633 German speaking children in 3rd and 4th Grade. Prevalence rates were analysed for isolated as well as combined Learning Disorders and for different deficit criteria, including a criterion for normal performance. Comorbid Learning Disorders occurred as frequently as isolated Learning Disorders, even when stricter cutoff criteria were applied. The relative proportion of isolated and combined Disorders did not change when including a criterion for normal performance. Reading and spelling deficits differed with respect to their association with arithmetic problems: Deficits in arithmetic co-occurred more often with deficits in spelling than with deficits in reading. In addition, comorbidity rates for arithmetic and reading decreased when applying stricter deficit criteria, but stayed high for arithmetic and spelling irrespective of the chosen deficit criterion. These findings suggest that the processes underlying the relationship between arithmetic and reading might differ from those underlying the relationship between arithmetic and spelling. With respect to gender ratios, more boys than girls showed spelling deficits, while more girls were impaired in arithmetic. No gender differences were observed for isolated reading problems and for the combination of all three Learning Disorders. Implications of these findings for assessment and intervention of Learning Disorders are discussed.