Publications by authors named "Jennifer L Howe"

Autism spectrum disorder (ASD) displays a notable male bias in prevalence. Research into rare (<0.1) genetic variants on the X chromosome has implicated over 20 genes in ASD pathogenesis, such as MECP2, DDX3X, and DMD.

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Autism spectrum disorder (ASD) exhibits an ∼4:1 male-to-female sex bias and is characterized by early-onset impairment of social/communication skills, restricted interests, and stereotyped behaviors. Disruption of the Xp22.11 locus has been associated with ASD in males.

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Autism Spectrum Disorder (ASD) displays a notable male bias in prevalence. Research into rare (<0.1) genetic variants on the X chromosome has implicated over 20 genes in ASD pathogenesis, such as , , and .

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We performed whole-genome sequencing (WGS) in 327 children with cerebral palsy (CP) and their biological parents. We classified 37 of 327 (11.3%) children as having pathogenic/likely pathogenic (P/LP) variants and 58 of 327 (17.

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Article Synopsis
  • Autism Spectrum Disorder (ASD) has a significant male-to-female ratio (~4:1) and is marked by social and communication difficulties, restricted interests, and repetitive behaviors.
  • Disruption of the Xp22.11 genetic region has been linked to ASD, highlighting the importance of specific genes and long noncoding RNAs in understanding the condition.
  • In a study of 31 individuals with ASD, rare genetic variants were found predominantly in a specific gene, suggesting a connection between this gene and ASD, which could influence future clinical testing and animal model research.
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  • The study investigates a new neurodevelopmental syndrome linked to loss-of-function variants in the ANK2 gene, associated with conditions like intellectual disability and autism.
  • Researchers used CRISPR technology to create human-induced pluripotent stem cells (hiPSCs) with these genetic variants, then differentiated these cells into neurons for further examination.
  • Findings revealed that ANK2-deficient neurons exhibited hyperactivity and lack of synchronization within neuronal networks, along with structural changes that affect their function and adaptability.
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Background: The X-linked PTCHD1 locus is strongly associated with autism spectrum disorder (ASD). Males who carry chromosome microdeletions of PTCHD1 antisense long non-coding RNA (PTCHD1-AS)/DEAD-box helicase 53 (DDX53) have ASD, or a sub-clinical form called Broader Autism Phenotype. If the deletion extends beyond PTCHD1-AS/DDX53 to the next gene, PTCHD1, which is protein-coding, the individuals typically have ASD and intellectual disability (ID).

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Article Synopsis
  • Full understanding of autism spectrum disorder (ASD) genetics requires whole-genome sequencing (WGS), highlighted by the latest Autism Speaks MSSNG resource that includes data from over 11,000 individuals.
  • The study found ASD-associated rare genetic variants in about 14% of individuals with ASD, examining data from MSSNG and the Simons Simplex Collection, which suggests similar prevalence in both datasets.
  • The identified variants were mostly nuclear (98%) with a small fraction being mitochondrial, and the research aims to help explore genetic links to ASD traits and identify causes for the 85% of ASD cases that currently lack identified genetic causes.
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  • Research identifies distinct genetic subtypes of autism spectrum disorder (ASD) by analyzing physical traits, categorizing 325 Canadian children with ASD into dysmorphic and nondysmorphic groups.
  • A novel genome-wide rare variant score (GRVS) was developed to assess genetic variants, revealing that children with dysmorphic ASD exhibit significantly higher GRVS than those without physical anomalies.
  • Additional analysis using a polygenic transmission test showed that common ASD variants are more prevalent in nondysmorphic probands, supporting a new classification approach based on morphology to guide treatment strategies.
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  • The study identifies a new autosomal dominant disorder linked to loss-of-function variants in the CAPRIN1 gene, which plays a role in neuronal mRNA transport and translation, affecting cognitive and developmental functions.
  • Out of 12 cases studied, patients exhibited a range of neurodevelopmental issues, including language impairments, intellectual disabilities, ADHD, and autism, along with various physical health problems.
  • Using CRISPR-Cas9 technology, the researchers created CAPRIN1 deficient stem cells, finding that the loss of this gene leads to disrupted neuronal organization, reduced neuronal function, and impaired calcium signaling, suggesting significant impacts on brain development and function.
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Autism Spectrum Disorder (ASD) is characterized by impaired social communication, restricted interests, and repetitive and stereotyped behaviors. The TRPC6 (transient receptor potential channel 6) represents an ASD candidate gene under an oligogenic/multifactorial model based on the initial description and cellular characterization of an individual with ASD bearing a de novo heterozygous mutation disrupting TRPC6, together with the enrichment of disruptive TRPC6 variants in ASD cases as compared to controls. Here, we perform a clinical re-evaluation of the initial non-verbal patient, and also present eight newly reported individuals ascertained for ASD and bearing predicted loss-of-function mutations in TRPC6.

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Autism spectrum disorder (ASD) is a collection of neurodevelopmental disorders characterized by deficits in social communication and restricted, repetitive patterns of behavior or interests. ASD is highly heritable, but genetically and phenotypically heterogeneous, reducing the power to identify causative genes. We performed whole genome sequencing (WGS) in an ASD cohort of 68 individuals from 22 families enriched for recent shared ancestry.

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PAX5 is a transcription factor associated with abnormal posterior midbrain and cerebellum development in mice. PAX5 is highly loss-of-function intolerant and missense constrained, and has been identified as a candidate gene for autism spectrum disorder (ASD). We describe 16 individuals from 12 families who carry deletions involving PAX5 and surrounding genes, de novo frameshift variants that are likely to trigger nonsense-mediated mRNA decay, a rare stop-gain variant, or missense variants that affect conserved amino acid residues.

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Background: In recent years, several hundred autism spectrum disorder (ASD) implicated genes have been discovered impacting a wide range of molecular pathways. However, the molecular underpinning of ASD, particularly from the point of view of 'brain to behaviour' pathogenic mechanisms, remains largely unknown.

Methods: We undertook a study to investigate patterns of spatiotemporal and cell type expression of ASD-implicated genes by integrating large-scale brain single-cell transcriptomes (> million cells) and de novo loss-of-function (LOF) ASD variants (impacting 852 genes from 40,122 cases).

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Article Synopsis
  • - Autism Spectrum Disorder (ASD) is influenced by a complex array of genetic factors, with around 100 known copy number variants and genes associated with the condition, prompting researchers to explore specific damaging mutations in affected genes.
  • - The study identified a common mutation in the SHANK3 gene (c.3679dup; p.Ala1227Glyfs*69) present in 18 individuals from 16 families, which is found in about 0.08% of those with ASD, with many individuals having new mutations while some inherited it through somatic mosaicism.
  • - Analysis of individuals with the SHANK3 mutation revealed that all tested had an ASD diagnosis, but the expression of core ASD features varied significantly
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  • Tandem DNA repeats are sequences in the genome that can vary in size and are linked to over 40 genetic disorders, although their role in complex genetics remains unclear.
  • A study on 17,231 genomes of families with autism spectrum disorder (ASD) found significant variations in these repeats, particularly at certain loci associated with nervous system development.
  • The research indicates that rare expansions of these tandem repeats, more prevalent in individuals with ASD compared to their non-ASD siblings, may contribute to the risk of ASD and are linked to lower IQ and adaptive abilities.
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Autism spectrum disorder (ASD) is a relatively common childhood onset neurodevelopmental disorder with a complex genetic etiology. While progress has been made in identifying the de novo mutational landscape of ASD, the genetic factors that underpin the ASD's tendency to run in families are not well understood. In this study, nine extended pedigrees each with three or more individuals with ASD, and others with a lesser autism phenotype, were phenotyped and genotyped in an attempt to identify heritable copy number variants (CNVs).

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Copy number variations (CNVs) are implicated across many neurodevelopmental disorders (NDDs) and contribute to their shared genetic etiology. Multiple studies have attempted to identify shared etiology among NDDs, but this is the first genome-wide CNV analysis across autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia (SCZ), and obsessive-compulsive disorder (OCD) at once. Using microarray (Affymetrix CytoScan HD), we genotyped 2,691 subjects diagnosed with an NDD (204 SCZ, 1,838 ASD, 427 ADHD and 222 OCD) and 1,769 family members, mainly parents.

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Unlabelled: Induced pluripotent stem cell (iPSC)-derived neurons are increasingly used to model Autism Spectrum Disorder (ASD), which is clinically and genetically heterogeneous. To study the complex relationship of penetrant and weaker polygenic risk variants to ASD, 'isogenic' iPSC-derived neurons are critical. We developed a set of procedures to control for heterogeneity in reprogramming and differentiation, and generated 53 different iPSC-derived glutamatergic neuronal lines from 25 participants from 12 unrelated families with ASD.

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Autism spectrum disorder (ASD) is phenotypically and genetically heterogeneous. We present a CRISPR gene editing strategy to insert a protein tag and premature termination sites creating an induced pluripotent stem cell (iPSC) knockout resource for functional studies of ten ASD-relevant genes (AFF2/FMR2, ANOS1, ASTN2, ATRX, CACNA1C, CHD8, DLGAP2, KCNQ2, SCN2A, TENM1). Neurogenin 2 (NGN2)-directed induction of iPSCs allowed production of excitatory neurons, and mutant proteins were not detectable.

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Background: Although several genetic variants for autism spectrum disorder (ASD) have now been identified, these largely occur sporadically or are de novo. Much less progress has been made in identifying inherited variants, even though the disorder itself is familial in the majority of cases. The objective of this study was to identify chromosomal regions that harbor inherited variants increasing the risk for ASD using an approach that examined both ASD and the broad autism phenotype (BAP) among a unique sample of extended pedigrees.

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Background: Autism spectrum disorder (ASD), a developmental disorder of early childhood onset, affects males four times more frequently than females, suggesting a role for the sex chromosomes. In this study, we describe a family with ASD in which a predicted pathogenic nonsense mutation in the X-chromosome gene segregates with ASD phenotype.

Methods: Clinical phenotyping, microarray, and whole genome sequencing (WGS) were performed on the five members of this family.

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We are performing whole-genome sequencing of families with autism spectrum disorder (ASD) to build a resource (MSSNG) for subcategorizing the phenotypes and underlying genetic factors involved. Here we report sequencing of 5,205 samples from families with ASD, accompanied by clinical information, creating a database accessible on a cloud platform and through a controlled-access internet portal. We found an average of 73.

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Article Synopsis
  • Mutations (DNMs) play a significant role in Autism Spectrum Disorder (ASD), with whole genome sequencing revealing that 75.6% of germline DNMs come from fathers, particularly increasing with paternal age.
  • Clustering of DNMs in ASD cases is more likely to originate from mothers and is often found near elevated mutation rates associated with copy number variations (CNVs).
  • An analysis of DNM patterns shows a higher occurrence of damaging DNMs in ASD cases, including significant contributions from non-coding regions, suggesting that non-coding variants may influence the genetic landscape of ASD.
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