Similar Datasets
Project description:Human Cortical DNA methylation by WGBS in Autism Spectrum Disorders and Rett Syndrome
| PRJNA490887 | ENA
Project description:Genome-wide DNA methylation profiling of postmortem brain tissue in the subventricular zone of the lateral ventricles from individuals with autism and without.
2019-10-16 | GSE131706 | GEO
Project description:Genome-wide DNA methylation profiling of ASD and controls using peripheral blood samples.
2019-09-23 | GSE109905 | GEO
Project description:Rett syndrome (RTT, MIM#312750) is a neurodevelopmental disorder that is classified as an autism spectrum disorder. Clinically, RTT is characterized by psychomotor regression with loss of volitional hand use and spoken language, the development of repetitive hand stereotypies, and gait impairment. The majority of people with RTT have mutations in Methyl-CpG-binding Protein 2 (MECP2), a transcriptional regulator. Interestingly, alterations in the function of the protein product produced by MECP2, MeCP2, have been identified in a number of other clinical conditions. The many clinical features found in RTT and the various clinical problems that result from alteration in MeCP2 function have led to the belief that understanding RTT will provide insight into a number of other neurological disorders. Excitingly, RTT is reversible in a mouse model, providing inspiration and hope that such a goal may be achieved for RTT and potentially for many neurodevelopmental disorders.
| S-EPMC3513680 | biostudies-literature
Project description:Autism is currently considered a multigene disorder with epigenetic influences. To investigate the contribution of DNA methylation to autism spectrum disorders, we have recently completed large-scale methylation profiling by CpG island microarray analysis of lymphoblastoid cell lines (LCL) derived from monozygotic twins discordant for diagnosis of autism and their nonautistic siblings. Methylation profiling revealed many candidate genes differentially methylated between discordant MZ twins as well as between both twins and nonautistic siblings. Bioinformatics analysis of the differentially methylated genes demonstrated enrichment for high level functions including gene transcription, nervous system development, cell death/survival, and other biological processes implicated in autism. The methylation status of two of these candidate genes, BCL-2 and retinoic acid receptor (RAR)-related orphan receptor alpha (RORA), was further confirmed by bisulfite sequencing and methylation-specific PCR, respectively. Immunohistochemical analyses of tissue arrays containing slices of the cerebellum and frontal cortex of autistic and age- and sex-matched control subjects revealed decreased expression of RORA and BCL-2 proteins in the autistic brain. Our data thus confirm the role of epigenetic regulation of gene expression via differential DNA methylation in idiopathic autism, and furthermore link molecular changes in a peripheral cell model with brain pathobiology in autism.
2010-04-27 | GSE21395 | GEO
Project description:Rett syndrome (RTT) is a severe neurodevelopmental disorder that constitutes the second most common cause of intellectual disability in females worldwide. In the past few years, the advancements in genetic diagnosis brought by next generation sequencing (NGS), have made it possible to identify more than 90 causative genes for RTT and significantly overlapping phenotypes (RTT spectrum disorders). Therefore, the clinical entity known as RTT is evolving towards a spectrum of overlapping phenotypes with great genetic heterogeneity. Hence, simultaneous multiple gene testing and thorough phenotypic characterization are mandatory to achieve a fast and accurate genetic diagnosis. In this review, we revise the evolution of the diagnostic process of RTT spectrum disorders in the past decades, and we discuss the effectiveness of state-of-the-art genetic testing options, such as clinical exome sequencing and whole exome sequencing. Moreover, we introduce recent technological advancements that will very soon contribute to the increase in diagnostic yield in patients with RTT spectrum disorders. Techniques such as whole genome sequencing, integration of data from several "omics", and mosaicism assessment will provide the tools for the detection and interpretation of genomic variants that will not only increase the diagnostic yield but also widen knowledge about the pathophysiology of these disorders.
| S-EPMC8508637 | biostudies-literature
Project description:In this study, whole genome sequencing was performed in two autistic families (as trio).
| PRJEB34754 | ENA
Project description:Autism Spectrum Disorder (ASD) is a complex neuropsychiatric syndrome whose etiology includes genetic and environmental components. Since epigenetic marks are sensitive to environmental insult, they may be involved in the development of ASD. Initial brain studies have suggested a dysregulation of epigenetic marks in ASD. However, due to cellular heterogeneity in the brain, these studies have not determined if there is a true change in the neuronal epigenetic signature. Here, we report a genome-wide methylation study on fluorescence-activated cell sorting-sorted neuronal nuclei from the frontal cortex of 16 male ASD and 15 male control subjects. Using the 450 K BeadArray, we identified 58 differentially methylated regions (DMRs) that included loci associated to GABAergic system genes, particularly ABAT and GABBR1, and brain-specific MicroRNAs. Selected DMRs were validated by targeted Next Generation Bisulfite Sequencing. Weighted gene correlation network analysis detected 3 co-methylation modules which are significantly correlated to ASD that were enriched for genomic regions underlying neuronal, GABAergic, and immune system genes. Finally, we determined an overlap of the 58 ASD-related DMRs with neurodevelopment associated DMRs. This investigation identifies alterations in the DNA methylation pattern in ASD cortical neurons, providing further evidence that epigenetic alterations in disorder-relevant tissues may be involved in the biology of ASD.
| S-EPMC6346295 | biostudies-literature
Project description:BACKGROUND:Perturbations to the microscopic level balance between synaptic excitation and inhibition and neuron organization in the cerebral cortex are suggested to underlie autism spectrum disorder (ASD) traits. The mechanism linking these perturbations to cognitive behaviors in ASD is unknown. This study strives to bridge this gap by generating clinically testable diagnostic and pharmacological predictions based on the effect of synaptic imbalance and neuron distribution on a computational local circuit model of the cerebral cortex. METHODS:We use a computational microscopic model of the cerebral cortex that incorporates N-methyl-D-aspartate and gamma-aminobutyric acid synaptic kinetics. We employ the model circuit during model tasks similar to visually guided and gap oculomotor saccade tasks and interpret qualitative model predictions of saccade hypometria and dysmetria. We consider the effects of varying the excitatory to inhibitory synaptic balance, neuron density, and neuron clustering in this model. RESULTS:An increase of synaptic excitation over synaptic inhibition results in increased hypometria and dysmetria. Similar effects by either reduced inhibition or increased excitation suggest that a variety of pharmacological compounds can be used for both screening and medical management. On the other hand, any change to the microscopic neuron anatomy that increases the effective maximum distance between excitatory neurons decreases hypometria but has no affect on dysmetria. CONCLUSIONS:Perturbations to a computational model of a local cerebral cortical circuit can account for saccade hypometria and dysmetria reported in ASD studies. This approach may provide a direct link between cerebral cortical function and ASD behaviors.
| S-EPMC3104404 | biostudies-literature
Project description:Studies of head size and brain volume in autism spectrum disorders have suggested that early cortical overgrowth may be followed by prematurely arrested growth. However, the few investigations quantifying cortical thickness have yielded inconsistent results, probably due to variable ages and/or small sample sizes. We assessed differences in cortical thickness between high-functioning adolescent and young adult males with autism spectrum disorders (n = 41) and matched typically developing males (n = 40). We hypothesized thinner cortex, particularly in frontal, parietal and temporal regions, for individuals with autism spectrum disorders in comparison with typically developing controls. Furthermore, we expected to find an age × diagnosis interaction: with increasing age, more pronounced cortical thinning would be observed in autism spectrum disorders than typically developing participants. T(1)-weighted magnetization prepared rapid gradient echo 3 T magnetic resonance imaging scans were acquired from high-functioning males with autism spectrum disorders and from typically developing males matched group-wise on age (range 12-24 years), intelligence quotient (≥ 85) and handedness. Both gyral-level and vertex-based analyses revealed significantly thinner cortex in the autism spectrum disorders group that was located predominantly in left temporal and parietal regions (i.e. the superior temporal sulcus, inferior temporal, postcentral/superior parietal and supramarginal gyri). These findings remained largely unchanged after controlling for intelligence quotient and after accounting for psychotropic medication usage and comorbid psychopathology. Furthermore, a significant age × diagnosis interaction was found in the left fusiform/inferior temporal cortex: participants with autism spectrum disorders had thinner cortex in this region with increasing age to a greater degree than did typically developing participants. Follow-up within group comparisons revealed significant age-related thinning in the autism spectrum disorders group but not in the typically developing group. Both thinner temporal and parietal cortices during adolescence and young adulthood and discrepantly accelerated age-related cortical thinning in autism spectrum disorders suggest that a second period of abnormal cortical growth (i.e. greater thinning) may be characteristic of these disorders.
| S-EPMC2995883 | biostudies-literature