Project description:To examine how activation of different toll-like receptors (TLR) impacts gene expression in Autism Spectrum Disorder (ASD), we cultured peripheral blood monocytes from children with ASD, Pervasive Developmental Disorder Not Otherwise Specified (PDDNOS) or Asperger and typically developing children and treated them with either lipoteichoic acid (LTA) or lipopolysaccharide (LPS) to activate LTR2 or 4 respectively. Following 24 hours of stimulation, we then performed RNA sequencing to profile mRNA responses between non-treated (NT), LTA and LPS treated samples for each diagnosis (control or ASD).
Project description:Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by delayed/abnormal language development, deficits in social interaction, repetitive behaviors and restricted interests. The heterogeneity in clinical presentation of ASD, likely due to different etiologies, complicates genetic/biological analyses of these disorders. DNA microarray analyses were conducted on 116 lymphoblastoid cell lines (LCL) from individuals with idiopathic autism who are divided into 3 phenotypic subgroups according to severity scores from the commonly used Autism Diagnostic Interview-Revised questionnaire and age-matched, nonautistic controls. Statistical analyses of gene expression data from control LCL against that of LCL from ASD probands identify genes for which expression levels are either quantitatively or qualitatively associated with phenotypic severity. Comparison of the significant differentially expressed genes from each subgroup relative to the control group reveals differentially expressed genes unique to each subgroup as well as genes in common across subgroups. Among the findings unique to the most severely affected ASD group are genes that regulate circadian rhythm, which has been shown to have multiple effects on neurological as well as metabolic functions commonly dysregulated in autism. Among the genes common to all 3 subgroups of ASD are 5 novel genes which appear to associate with androgen sensitivity, which may underlie the strong 4:1 bias towards affected males. Gene expression profiling of 116 LCL from autistic (87) and nonautistic (29) individuals were obtained using a custom-printed DNA microarray containing 39,936 elements (TIGR 40K Human array, GPL3427) and a reference design in which each sample was compared to the Stratagene Universal Human RNA standard. The 87 autistic samples were divided into phenotypic subgroups (language, mild, savant) on the basis of cluster analyses of scores from an autism diagnostic questionnaire, the Autism Diagnostic Interview-Revised instrument. Differentially expressed genes were determined for all autistic vs. control groups, as well as for each of 3 phenotypic ASD groups and controls.
Project description:Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by delayed/abnormal language development, deficits in social interaction, repetitive behaviors and restricted interests. The heterogeneity in clinical presentation of ASD, likely due to different etiologies, complicates genetic/biological analyses of these disorders. DNA microarray analyses were conducted on 116 lymphoblastoid cell lines (LCL) from individuals with idiopathic autism who are divided into 3 phenotypic subgroups according to severity scores from the commonly used Autism Diagnostic Interview-Revised questionnaire and age-matched, nonautistic controls. Statistical analyses of gene expression data from control LCL against that of LCL from ASD probands identify genes for which expression levels are either quantitatively or qualitatively associated with phenotypic severity. Comparison of the significant differentially expressed genes from each subgroup relative to the control group reveals differentially expressed genes unique to each subgroup as well as genes in common across subgroups. Among the findings unique to the most severely affected ASD group are genes that regulate circadian rhythm, which has been shown to have multiple effects on neurological as well as metabolic functions commonly dysregulated in autism. Among the genes common to all 3 subgroups of ASD are 5 novel genes which appear to associate with androgen sensitivity, which may underlie the strong 4:1 bias towards affected males.
Project description:Fragile X syndrome and tuberous sclerosis are genetic syndromes that both have a high rate of co-morbidity with autism spectrum disorders. Several lines of evidences suggest that these two monogenic disorders may converge at a molecular level through the dysfunction of activity-dependent synaptic plasticity. We utilized mouse models of these monogenic disorders to identify genome-wide transcriptional changes in cerebellum and blood and characterize the (dis-)similarity of their molecular signatures. Differentially expressed genes and enriched pathways were distinct for the two mouse models examined, with the exception of immune system related pathways. In the cerebellum of the Fmr1 knockout (Fmr1-KO) model, the neuroactive ligand receptor interaction pathway and gene sets associated with synaptic plasticity such as long term potentiation, gap junction, and axon guidance were the most significantly perturbed pathways. The phosphatidylinositol signaling pathway was significantly dysregulated in both blood and brain of Fmr1-KO mice. In both the blood and brain of the Tsc2 heterozygous mouse model, immune system related pathways, genes encoding ribosomal proteins, and glycolipid metabolism pathways were significantly perturbed. Our data suggest that distinct molecular pathways may be involved in autism spectrum disorders with known but different genetic causes, and that blood gene expression profiles of Fmr1-knockout and Tsc2+/- mice mirror some, but not all, of the perturbed molecular pathways in the brain. For the Fmr1-KO model, 10 mice, consisting of 5 KO and 5 WT mice, were profiled. Thus, 10 pairs of blood and cerebella samples were profiled. Likewise, for the Tsc+/- model, 3 transgenic and 3 WT mice were sacrificed and paired blood and cerebella samples were prepared for gene expression profiling. All samples were profiled using the Affymetrix Mouse Gene ST 1.0 ST arrays. Three factors—tissue (i.e. blood vs. cerebellum), treatment (i.e. knockout vs. wildtype), and genetic background (Fmr1-KO vs. Tsc2+/-)—were analyzed with analysis of variance (ANOVA). Subsequently, we compared blood and brain gene expression changes in Fmr1 and Tsc2 knockout mice models using WT littermates as controls using t-tests with unequal variances. The false discovery rate (FDR) was calculated using Storey and Tibshirani’s method.