Showing papers by "Herbert M. Lachman published in 2021"
TL;DR: In this article, the mechanism of gene-environment interactions and reliable bi-particle bi-connections were used to diagnose autism spectrum disorder (ASD) caused by complex genetic and environmental components.
Abstract: Background: Autism spectrum disorder (ASD) is a major public health concern caused by complex genetic and environmental components. Mechanisms of gene–environment (G×E) interactions and reliable bi...
29 citations
TL;DR: In this article, the authors carried out whole exome sequencing (WES) on a U.S. cohort of 386 cases who met diagnostic criteria for acute onset neuropsychiatric syndrome (PANS), including 133 family triads, and whole genome sequencing on ten cases from the European Union, who were selected for severe PANS symptoms.
Abstract: Pediatric acute onset neuropsychiatric syndrome (PANS) is viewed as an autoimmune/autoinflammatory condition characterized by the abrupt onset of severe neurological and psychiatric symptoms, in particular obsessive-compulsive disorder (OCD), tics, anxiety, mood swings, irritability, and restricted eating, often triggered by infections. However, direct evidence of autoimmunity, infections, or a proinflammatory state is often lacking, and there is no unifying pathogenic pathway. This could be due to underlying genetic heterogeneity, which could lead to the development of PANS through different cellular and molecular pathways. Unfortunately, little is known about the genetic basis of PANS. Consequently, we carried out whole exome sequencing (WES) on a U.S. cohort of 386 cases who met diagnostic criteria for PANS, including 133 family triads, and whole genome sequencing (WGS) on ten cases from the European Union, who were selected for WGS because of severe PANS symptoms. We focused on identifying potentially deleterious genetic variants that were either de novo or ultra-rare with a minor allele frequency (MAF) < 0.001. Candidate mutations were found in 11 genes: PPM1D, SGCE, PLCG2, NLRC4, CACNA1B, SHANK3, CHK2, GRIN2A, RAG1, GABRG2, and SYNGAP1 in a total of 20 cases, which included two sets of siblings, and two or more unrelated subjects with ultra-rare variants in SGCE, NLRC4, RAG1, and SHANK3. The PANS candidate genes we identified separate into two broad functional categories. One group regulates peripheral innate and adaptive immune responses (e.g., PPM1D, CHK2, NLRC4, RAG1, PLCG2), some of which also influence microglia function. Another is expressed primarily at neuronal synapses or directly modulates synaptic function (SHANK3, SYNGAP1, GRIN2A, GABRG2, CACNA1B, SGCE). These neuronal PANS candidate genes are often mutated in autism spectrum disorder, developmental disorders, and myoclonus-dystonia. In fact, eight out of 20 cases in this study developed PANS superimposed on a preexisting neurodevelopmental disorder. There is, however, clinical overlap between these two groups and some crossover expression (e.g., some neuronal genes are expressed in immune cells and vice versa) that diminishes the neuronal/immune dichotomy. Genes in both categories are also highly expressed in the enteric nervous system, and in the choroid plexus and brain vasculature, suggesting they might contribute to a breach in the blood-CSF barrier and blood-brain barrier (BBB) that would permit the entry of autoantibodies, inflammatory cytokines, chemokines, prostaglandins, and autoantibodies into the brain. Thus, PANS is a genetically heterogeneous condition that can occur as a stand-alone neuropsychiatric condition or co-morbid with neurodevelopmental disorders, with candidate genes functioning at several levels of the neuroinflammatory axis.
2 citations
TL;DR: In this paper, the authors apply advanced computation and pattern recognition approaches on single cell RNA-seq data to infer and compare inter-cell-type signaling communications in autism brains and controls, finding that at a global level there are cell-cell communication differences in autism in comparison to controls, largely involving neurons as both signaling senders and receivers.
Abstract: Autism spectrum disorder is a neurodevelopmental disorder, affecting 1-2% of children. Studies have revealed genetic and cellular abnormalities in the brains of affected individuals, leading to both regional and distal cell communication deficits. Recent application of single cell technologies, especially single cell transcriptomics, has significantly expanded our understanding of brain cell heterogeneity and further demonstrated that multiple cell types and brain layers or regions are perturbed in autism. The underlying high-dimensional single cell data provides opportunities for multi-level computational analysis that collectively can better deconvolute the molecular and cellular events altered in autism. Here, we apply advanced computation and pattern recognition approaches on single cell RNA-seq data to infer and compare inter-cell-type signaling communications in autism brains and controls. Our results indicate that at a global level there are cell-cell communication differences in autism in comparison to controls, largely involving neurons as both signaling senders and receivers, but glia also contribute to the communication disruption. Although the magnitude of change is moderate, we find that excitatory and inhibitor neurons are involved in multiple intercellular signaling that exhibit increased strengths in autism, such as NRXN and CNTN signaling. Not all genes in the intercellular signaling pathways are differentially expressed, but genes in the pathways are enriched for axon guidance, synapse organization, neuron migration, and other critical cellular functions. Furthermore, those genes are highly connected to and enriched for genes previously associated with autism risks. Overall, our proof-of-principle computational study using single cell data uncovers key intercellular signaling pathways that are potentially disrupted in the autism brains, suggesting that more studies examining cross-cell type affects can be valuable for understanding autism pathogenesis.