scholarly journals Systematic Reconstruction of Autism Biology with Multi-Level Whole Exome Analysis

2016 ◽  
Author(s):  
Weijun Luo ◽  
Chaolin Zhang ◽  
Cory R. Brouwer

AbstractWhole exome/genome studies on autism spectrum disorder (ASD) identified thousands of variants, yet not a coherent and systematic disease mechanism. We conduct novel integrated analyses across multiple levels on ASD exomes. These mutations do not recur or replicate at variant level, but significantly and increasingly so at gene and pathway level. Genetic association reveals a novel gene+pathway dual-hit model, better explaining ASD risk than the well-accepted mutation burden model.In multiple analyses with independent datasets, hundreds of variants or genes consistently converge to several canonical pathways. Unlike the reported gene groups or networks, these pathways define novel, relevant, recurrent and systematic ASD biology. At sub-pathway level, most variants disrupt the pathway-related gene functions, and multiple interacting variants spotlight key modules, e.g. cAMP second-messenger system and mGluR signaling regulation by GRK in synapses. At super-pathway level, these distinct pathways are highly interconnected, and further converge to a few biology themes, i.e. synaptic function, morphology and plasticity. Therefore, ASD is a not just multi-genic but a multi-pathway disease.

2021 ◽  
Vol 11 ◽  
Author(s):  
Li-Han Lin ◽  
Chung-Hsien Chou ◽  
Hui-Wen Cheng ◽  
Kuo-Wei Chang ◽  
Chung-Ji Liu

Understanding the genomic alterations in oral carcinogenesis remains crucial for the appropriate diagnosis and treatment of oral squamous cell carcinoma (OSCC). To unveil the mutational spectrum, in this study, we conducted whole-exome sequencing (WES), using six mutation calling pipelines and multiple filtering criteria applied to 50 paired OSCC samples. The tumor mutation burden extracted from the data set of somatic variations was significantly associated with age, tumor staging, and survival. Several genes (MUC16, MUC19, KMT2D, TTN, HERC2) with a high frequency of false positive mutations were identified. Moreover, known (TP53, FAT1, EPHA2, NOTCH1, CASP8, and PIK3CA) and novel (HYDIN, ALPK3, ASXL1, USP9X, SKOR2, CPLANE1, STARD9, and NSD2) genes have been found to be significantly and frequently mutated in OSCC. Further analysis of gene alteration status with clinical parameters revealed that canonical pathways, including clathrin-mediated endocytotic signaling, NFκB signaling, PEDF signaling, and calcium signaling were associated with OSCC prognosis. Defining a catalog of targetable genomic alterations showed that 58% of the tumors carried at least one aberrant event that may potentially be targeted by approved therapeutic agents. We found molecular OSCC subgroups which were correlated with etiology and prognosis while defining the landscape of major altered events in the coding regions of OSCC genomes. These findings provide information that will be helpful in the design of clinical trials on targeted therapies and in the stratification of patients with OSCC according to therapeutic efficacy.


2020 ◽  
Vol 20 (11) ◽  
pp. 875-886
Author(s):  
Yingyi Wang ◽  
Bao Jin ◽  
Na Zhou ◽  
Zhao Sun ◽  
Jiayi Li ◽  
...  

Background:: Neoantigens are newly formed antigens that have not been previously recognized by the immune system. They may arise from altered tumor proteins that form as a result of mutations. Although neoantigens have recently been linked to antitumor immunity in long-term survivors of cancers, such as melanoma and colorectal cancer, their prognostic and immune-modulatory role in many cancer types remains undefined. Objective: The purpose of this study is to identify prognostic markers for long-term extrahepatic cholangiocarcinoma (EHCC) survival. Methods: We investigated neoantigens in EHCC, a rare, aggressive cancer with a 5-year overall survival rate lower than 10%, using a combination of whole-exome sequencing (WES), RNA sequencing (RNA-seq), computational biophysics, and immunohistochemistry. Results: : Our analysis revealed a decreased neutrophil infiltration-related trend of high-quality neoantigen load with IC50 <500 nM (r=-0.445, P=0.043). Among 24 EHCC patients examined, we identified four long-term survivors with WDFY3 neoantigens and none with WDFY3 neoantigens in the short-term survivors. The WDFY3 neoantigens are associated with a lower infiltration of neutrophils (p=0.013), lower expression of CCL5 (p=0.025), CXCL9 (p=0.036) and TIGIT (p=0.016), and less favorable prognosis (p=0.030). In contrast, the prognosis was not significantly associated with tumor mutation burden, neoantigen load, or immune cell infiltration. Conclusion:: We suggest that the WDFY3 neoantigens may affect prognosis by regulating antitumor immunity and that the WDFY3 neoantigens may be harnessed as potential targets for immunotherapy of EHCC.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Freddy Zhang ◽  
Benjamin Rein ◽  
Ping Zhong ◽  
Treefa Shwani ◽  
Megan Conrow-Graham ◽  
...  

AbstractAutism spectrum disorder (ASD) is a lifelong developmental disorder characterized by social deficits and other behavioral abnormalities. Dysregulation of epigenetic processes, such as histone modifications and chromatin remodeling, have been implicated in ASD pathology, and provides a promising therapeutic target for ASD. Haploinsufficiency of the SHANK3 gene is causally linked to ASD, so adult (3–5 months old) Shank3-deficient male mice were used in this drug discovery study. We found that combined administration of the class I histone deacetylase inhibitor Romidepsin and the histone demethylase LSD1 inhibitor GSK-LSD1 persistently ameliorated the autism-like social preference deficits, while each individual drug alone was largely ineffective. Another behavioral abnormality in adult Shank3-deficient male mice, heightened aggression, was also alleviated by administration of the dual drugs. Furthermore, Romidepsin/GSK-LSD1 treatment significantly increased transcriptional levels of NMDA receptor subunits in prefrontal cortex (PFC) of adult Shank3-deficient mice, resulting in elevated synaptic expression of NMDA receptors and the restoration of NMDAR synaptic function in PFC pyramidal neurons. These results have offered a novel pharmacological intervention strategy for ASD beyond early developmental periods.


2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Marta Codina-Solà ◽  
Benjamín Rodríguez-Santiago ◽  
Aïda Homs ◽  
Javier Santoyo ◽  
Maria Rigau ◽  
...  

2018 ◽  
Vol 115 (12) ◽  
pp. 3168-3173 ◽  
Author(s):  
Amanda K. Tilot ◽  
Katerina S. Kucera ◽  
Arianna Vino ◽  
Julian E. Asher ◽  
Simon Baron-Cohen ◽  
...  

Synesthesia is a rare nonpathological phenomenon where stimulation of one sense automatically provokes a secondary perception in another. Hypothesized to result from differences in cortical wiring during development, synesthetes show atypical structural and functional neural connectivity, but the underlying molecular mechanisms are unknown. The trait also appears to be more common among people with autism spectrum disorder and savant abilities. Previous linkage studies searching for shared loci of large effect size across multiple families have had limited success. To address the critical lack of candidate genes, we applied whole-exome sequencing to three families with sound–color (auditory–visual) synesthesia affecting multiple relatives across three or more generations. We identified rare genetic variants that fully cosegregate with synesthesia in each family, uncovering 37 genes of interest. Consistent with reports indicating genetic heterogeneity, no variants were shared across families. Gene ontology analyses highlighted six genes—COL4A1, ITGA2, MYO10, ROBO3, SLC9A6, and SLIT2—associated with axonogenesis and expressed during early childhood when synesthetic associations are formed. These results are consistent with neuroimaging-based hypotheses about the role of hyperconnectivity in the etiology of synesthesia and offer a potential entry point into the neurobiology that organizes our sensory experiences.


2019 ◽  
Author(s):  
Jennifer K. Forsyth ◽  
Daniel Nachun ◽  
Michael J. Gandal ◽  
Daniel H. Geschwind ◽  
Ariana E. Anderson ◽  
...  

AbstractBackground22q11.2 copy number variants (CNVs) are among the most highly penetrant genetic risk variants for developmental neuropsychiatric disorders such as schizophrenia (SCZ) and autism spectrum disorder (ASD). However, the specific mechanisms through which they confer risk remain unclear.MethodsUsing a functional genomics approach, we integrated transcriptomic data from the developing human brain, genome-wide association findings for SCZ and ASD, protein interaction data, and pathophysiological signatures of SCZ and ASD to: 1) organize genes into the developmental cellular and molecular systems within which they operate; 2) identify neurodevelopmental processes associated with polygenic risk for SCZ and ASD across the allelic frequency spectrum; and 3) elucidate pathways and individual genes through which 22q11.2 CNVs may confer risk for each disorder.ResultsPolygenic risk for SCZ and ASD converged on partially overlapping gene networks involved in synaptic function and transcriptional regulation, with ASD risk variants additionally enriched for networks involved in neuronal differentiation during fetal development. The 22q11.2 locus formed a large protein network that disproportionately affected SCZ- and ASD-associated neurodevelopmental networks, including loading highly onto synaptic and gene regulatory pathways. SEPT5, PI4KA, and SNAP29 genes are candidate drivers of 22q11.2 synaptic pathology relevant to SCZ and ASD, and DGCR8 and HIRA are candidate drivers of disease-relevant alterations in gene regulation.ConclusionsThe current approach provides a powerful framework to identify neurodevelopmental processes affected by diverse risk variants for SCZ and ASD, and elucidate the mechanisms through which highly penetrant multi-gene CNVs contribute to disease risk.


Author(s):  
Valentin Hess ◽  
Justine Miguel ◽  
Chrystèle Bonnemains ◽  
Claire Bilbault

AbstractSynaptic Ras GTPase-activating protein 1 (SYNGAP1), also called Ras-GAP 1 or RASA5, is a cerebral protein with a role in brain synaptic function. Its expression affects the development, structure, function, and plasticity of neurons. Mutations in the gene cause a neurodevelopment disorder termed mental retardation-type 5, also called SYNGAP1 syndrome. This syndrome can cause many neurological symptoms including pharmaco-resistant epilepsy, intellectual disability, language delay, and autism spectrum disorder. The syndrome naturally evolves as epileptic encephalopathy with handicap and low intellectual level. A treatment to control epilepsy, limit any decrease in social capacities, and improve intellectual development is really a challenging goal for these patients. The etiologic investigation performed in a 5-year-old girl with early epileptic absence seizures (onset at 6 months) and psychomotor delay (language) revealed a low methylenetetrahydrofolate level in cerebrospinal fluid in a lumbar puncture, confirmed by a second one (35 nmol/L and 50 nmol/L vs. 60–100 nmol/L normal), associated with normal blood and erythrocyte folate levels. Hyperhomocysteinemia, de vivo disease, and other metabolic syndromes were excluded by metabolic analysis. No genetic disorders (like methylenetetrahydrofolate reductase and methenyltetrahydrofolate synthetase) with folate metabolism were found. The physical examination showed only a minor kinetic ataxia. An oral folate (5-methyltetrahydrofolate) supplementation was started with oral vitamin therapy. The child showed good progress in language with this new treatment; epilepsy was well balanced with only one antiepileptic drug. The SYNGAP1 mutation was identified in this patient's genetic analysis. Since the start of folate supplementation/vitamin therapy, the patient's neurologic development has improved. To our knowledge, no association between these two pathologies has been linked and no patient with this SYNGAP1 mutation has ever showed much intellectual progress. Low cerebral methylenetetrahydrofolate levels could be associated with SYNGAP1 mutations. One of the hypotheses is the link of folate metabolism with epigenetic changes including methylation process. One inborn metabolic activity in folate metabolism may be associated with SYNGAP1 disease with epigenetic repercussions. Further studies should assess the link of SYNGAP1 and methyltetrahydrofolate and the evolution of SYNGAP1 patients with oral folate supplementation or vitamin therapy.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Cristina Cheroni ◽  
Nicolò Caporale ◽  
Giuseppe Testa

Abstract The complex pathophysiology of autism spectrum disorder encompasses interactions between genetic and environmental factors. On the one hand, hundreds of genes, converging at the functional level on selective biological domains such as epigenetic regulation and synaptic function, have been identified to be either causative or risk factors of autism. On the other hand, exposure to chemicals that are widespread in the environment, such as endocrine disruptors, has been associated with adverse effects on human health, including neurodevelopmental disorders. Interestingly, experimental results suggest an overlap in the regulatory pathways perturbed by genetic mutations and environmental factors, depicting convergences and complex interplays between genetic susceptibility and toxic insults. The pervasive nature of chemical exposure poses pivotal challenges for neurotoxicological studies, regulatory agencies, and policy makers. This highlights an emerging need of developing new integrative models, including biomonitoring, epidemiology, experimental, and computational tools, able to capture real-life scenarios encompassing the interaction between chronic exposure to mixture of substances and individuals’ genetic backgrounds. In this review, we address the intertwined roles of genetic lesions and environmental insults. Specifically, we outline the transformative potential of stem cell models, coupled with omics analytical approaches at increasingly single cell resolution, as converging tools to experimentally dissect the pathogenic mechanisms underlying neurodevelopmental disorders, as well as to improve developmental neurotoxicology risk assessment.


2018 ◽  
Vol 24 (9) ◽  
pp. 995-1002 ◽  
Author(s):  
Alexander Tan ◽  
Kimberly Goodspeed ◽  
Veronica Bordes Edgar

AbstractObjectives: Pitt-Hopkins syndrome (PTHS) is a rare genetic disorder caused by insufficient expression of the TCF4 gene. Most cases are characterized by severe intellectual disability, absent speech, motor delays, and autism spectrum disorder. Many have abnormal brain imaging, dysmorphic facial features, and medical comorbidities: myopia, constipation, epilepsy, and apneic spells. The present case study expands existing understanding of this disorder by presenting a unique phenotype with higher cognitive abilities and fewer medical comorbidities. Methods: The present case study reports on a 13-year-old, Caucasian male with a recent diagnosis of PTHS following genetic testing (i.e., whole exome sequencing). He was referred for a neuropsychological evaluation to document his neurocognitive functioning to assist with intervention planning. Results: Evaluation of intellectual, attention/executive, memory, visual-motor/fine-motor, academic, adaptive, and emotional/behavioral functioning revealed global impairment across all areas of functioning. However, he demonstrated abilities beyond what has been detailed in the literature, including use of full sentences, capacity to learn and solve novel problems, basic academic functioning, and independent ambulation. Conclusions: Children with PTHS may demonstrate a spectrum of abilities beyond what has been documented in the literature thus far. Failure to recognize this spectrum can result in late identification of an accurate diagnosis. (JINS, 2018, 24, 995–1002)


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