Project description:Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social communication deficits and repetitive behaviors. MicroRNAs (miRNAs) have been recently recognized as potential biomarkers of ASD as they are dysregulated in various tissues of individuals with ASD. However, it remains unclear whether miRNA expression is altered in individuals with high-functioning ASD. Here, we investigated the miRNA expression profile in peripheral blood from adults with high-functioning ASD, and age and gender-matched healthy controls. Our findings may provide insights regarding the molecular clues for recognizing high-functioning ASD.
Project description:Chromosomal abnormalities have been identified in some individuals with Autism Spectrum Disorder (ASD), but their full etiologic role is unknown. Submicroscopic copy number variation (CNV) represents a considerable source of genetic variation in the human genome that contributes to phenotypic differences and disease susceptibility. To explore the contribution CNV imbalances in ASD, we genotyped unrelated ASD index cases using the Affymetrix GeneChip® 500K single nucleotide polymorphism (SNP) mapping array. Keywords: Whole Genome Mapping SNP Genotyping Array
Project description:Autism spectrum disorder (ASD) is a complex heterogeneous developmental disease with a significant genetic background that is frequently caused by rare copy number variants (CNV). The aim of the study was to identify new candidate genes for ASD in the studied cohort of ASD-diagnosed patients. We used chromosomal microarray analysis (CMA) - a Cytoscan HD (Affymetrix, Santa Clara, CA, USA) to detect CNV in 87 ASD patients and their relatives and evaluated their clinical significance. Pathogenic and likely pathogenic mutations were identified by CMA in 8 and 9 ASD patients, respectively. CMA revealed 89 rare CNV: 8 pathogenic, 12 designated VOUS - likely pathogenic, 12 VOUS - uncertain, and 57 VOUS - likely benign or benign. CNV (pathogenic/VOUS-likely pathogenic/VOUS - uncertain) overlapping the same gene in more than one patient were observed in DOCK8 gene and PARK2 gene. This work presents new evidence about the possible roles of PARK2 and DOCK8 in the etiology of ASD, and suggests CTNNA2 as a candidate gene for ASD risk.
Project description:To assess the clinical impact of splice-altering noncoding mutations in autism spectrum disorder (ASD), we used a deep learning framework (SpliceAI) to predict the splice-altering potential of de novo mutations in 3,953 individuals with ASD from the Simons Simplex Collection. To validate these predictions, we selected 36 individuals that harbored predicted de-novo cryptic splice mutations; each individual represented the only case of autism within their immediate family. We obtained peripheral blood-derived lymphoblastoid cell lines (LCLs) and performed high-depth mRNA sequencing (approximately 350 million 150 bp single-end reads per sample). We used OLego to align the reads against a reference created from hg19 by substituting de novo variants of each individual with the corresponding alternate allele.
Project description:Autism spectrum disorder (ASD) diagnosis is increasing, with 1/88 children believed to be affected by the disorder, with a most recent survey suggesting numbers as high as 1/50. Treatment and understanding of ASD causes is a pressing health concern. ASD protein biomarkers may provide clues about ASD cause. Protein biomarkers for ASDs could be used for ASD diagnosis, subtyping, treatment monitoring and identifying therapeutic targets. Here we analyzed the sera from 7 children with ASD and 7 matched controls using Tricine gel electrophoresis (Tricine-PAGE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Overall, we found increased levels of apolipoproteins (Apos) ApoA1 and ApoA4, involved in cholesterol metabolism and of serum paraoxanase/arylesterase 1 (PON1), involved in preventing oxidative damage, in the sera of children with ASD, compared with their matched controls. All three proteins are predicted to interact with each other and are parts of High Density Lipoproteins (HDLs). Further studies are needed to validate these findings in larger subject numbers.
Project description:We transplanted gut microbiota via fecal transfer from TD and ASD children into germ-free wild-type mice, and reveal that colonization with ASD microbiomes induces hallmark changes in sociability, vocalization, and stereotypies. The brains of mice receiving gut microbiota from ASD individuals display alternative splicing patterns for genes dysregulated in the human ASD brain.
Project description:The aim of this study was to identify ASD vulnerability components, explore possible vulnerability subgroups, and evaluate environmental contribution to phenotypic variability. We performed PCA and cluster analysis using ASD risk factor data. We found that PC1 had a higher correlation with psychosocial stress (maternal stress, maternal education, and social class), and PC2 a higher correlation with biological factors (Psychiatric Family History and Gestational Complications). Clustering analysis of PCA scores using bootstrap approach showed two clusters. Comparing the methylome between clusters we found 11.879 DMPs (p<0.05), and their CpG sites were enriched in VMRs, most showing environmental and genetic influences. Hypermethylated probes presented higher rates in different regulatory regions associated with functional SNPs, indicating that the subgroups may have different affected regulatory regions and their liability to disease explained by common variations. Vulnerability score moderated by epigenetic clock was associated with Vineland Total score (p=0.0036, adjR2=0.31), suggesting risk factors with stress burden can influence phenotype.
Project description:We recently identified heterozygous deletions of the gene TSHZ3, which encodes a Zn-finger transcription factor, in patients with a syndrome including autistic features and provided evidence in mice for a link between Tshz3 haploinsufficiency, defects in cortical projection neurons (CPNs) and autism spectrum disorder (ASD)-like abnormalities. To get more insight into when and where TSHZ3 is required for the proper development of the brain, we generated and characterized a novel mouse model of conditional Tshz3 deletion in projection neurons from postnatal day 2-3 onward. These mice exhibit altered striatal expression of genes encoding for synaptic components, electrophysiological and synaptic changes in striatal cholinergic interneurons, , as well as ASD-relevant behavioral deficits. These data, by revealing a crucial postnatal role of TSHZ3 in the development and function of the corticostriatal circuitry that might be determinant for ASD pathogenesis, offer a novel ASD model and further open the possibility for an early postnatal therapeutic window for the syndrome linked to TSHZ3 haploinsufficiency.
Project description:Autism spectrum disorder (ASD) manifests as alterations in complex human behaviors including social communication and stereotypies. In addition to genetic risks, the gut microbiome differs between typically-developing (TD) and ASD individuals, though it remains unclear whether the microbiome contributes to symptoms. We transplanted gut microbiota from human donors with ASD and TD controls into germ-free mice, and reveal that colonization with ASD microbiota was sufficient to induce hallmark autistic behaviors. The brains of mice colonized with ASD microbiota display alternative splicing of ASD-relevant genes. Microbiome and metabolome profiles of mice harboring human microbiota predict that specific bacterial taxa and their metabolites modulate ASD behaviors. Indeed, treatment of an ASD mouse model with candidate microbial metabolites improves behavioral abnormalities and affects neuronal excitability in the brain. We propose that the gut microbiome modulates behaviors in mice via production of neuroactive metabolites, suggesting that gut-brain connections contribute to the pathophysiology of ASD.
Project description:We recently identified heterozygous deletions of the gene TSHZ3, which encodes a Zn-finger transcription factor, in patients with a syndrome including autistic features and provided evidence in mice for a link between Tshz3 haploinsufficiency, defects in cortical projection neurons (CPNs) and autism spectrum disorder (ASD)-like abnormalities. To get more insight into when and where TSHZ3 is required for the proper development of the brain, we generated and characterized a novel mouse model of conditional Tshz3 deletion in projection neurons from postnatal day 2-3 onward. These mice exhibit altered cortical expression of genes encoding for synaptic components, electrophysiological and synaptic changes in layer 5 CPNs, impaired corticostriatal glutamate transmission and plasticity, as well as strong ASD-relevant behavioral deficits. These data, by revealing a crucial postnatal role of TSHZ3 in the development and function of the corticostriatal circuitry that might be determinant for ASD pathogenesis, offer a novel ASD model and further open the possibility for an early postnatal therapeutic window for the syndrome linked to TSHZ3 haploinsufficiency.