Publications by authors named "Penny Snell"

The cerebellar ataxias (CAs) are a heterogeneous group of disorders characterized by progressive incoordination. Seventeen repeat expansion (RE) loci have been identified as the primary genetic cause and account for >80% of genetic diagnoses. Despite this, diagnostic testing is limited and inefficient, often utilizing single gene assays.

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Infantile epileptic spasms syndrome is a severe epilepsy of infancy that is often associated with focal malformations of cortical development. This study aimed to elucidate the genetic landscape and histopathologic aetiologies of infantile epileptic spasms syndrome due to focal malformations of cortical development requiring surgery. Fifty-nine children with a history of infantile epileptic spasms syndrome and focal malformations of cortical development on MRI were studied.

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Article Synopsis
  • - The study examines how secondary genetic variants can influence the clinical features of individuals with primary disease-causing variants, suggesting that these modifiers play a significant role in disease expression.
  • - Specifically focusing on the 16p12.1 deletion, researchers identified various rare and common variants that predisposed individuals to specific developmental issues, such as neurological defects and microcephaly.
  • - By analyzing data from different cohorts, the findings indicate that the effects of primary and secondary variants on phenotype vary depending on the specific primary variant involved, highlighting the need for personalized approaches in treatment.
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  • * The study identifies RNU4-2, a non-coding RNA gene, as a significant contributor to syndromic NDD, revealing a specific 18-base pair region with low variation that includes variants found in 115 individuals with NDD.
  • * RNU4-2 is highly expressed in the developing brain, and its variants disrupt splicing processes, indicating that non-coding genes play a crucial role in rare disorders, potentially aiding in the diagnosis of thousands with NDD worldwide.
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Around 60% of individuals with neurodevelopmental disorders (NDD) remain undiagnosed after comprehensive genetic testing, primarily of protein-coding genes. Increasingly, large genome-sequenced cohorts are improving our ability to discover new diagnoses in the non-coding genome. Here, we identify the non-coding RNA as a novel syndromic NDD gene.

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Article Synopsis
  • HCN gated channels play a vital role in brain functions like learning and sensory processing, and their dysfunction is linked to brain disorders, particularly epilepsy.
  • The study identifies 21 individuals with genetic variations associated with developmental delays, intellectual disabilities, and epilepsy, expanding our understanding of related disorders.
  • Functional tests on specific variants revealed that some mutations significantly increased HCN2 channel conductance, while others caused loss of function and impaired channel trafficking, suggesting diverse impacts of these variants on brain function.
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This study aimed to determine the diagnostic yield of singleton exome sequencing and subsequent research-based trio exome analysis in children with a spectrum of brain malformations seen commonly in clinical practice. We recruited children ≤ 18 years old with a brain malformation diagnosed by magnetic resonance imaging and consistent with an established list of known genetic causes. Patients were ascertained nationally from eight tertiary paediatric centres as part of the Australian Genomics Brain Malformation Flagship.

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We examined more than 97,000 families from four neurodevelopmental disease cohorts and the UK Biobank to identify phenotypic and genetic patterns in parents contributing to neurodevelopmental disease risk in children. We identified within- and cross-disorder correlations between six phenotypes in parents and children, such as obsessive-compulsive disorder (R = 0.32-0.

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We examined more than 38,000 spouse pairs from four neurodevelopmental disease cohorts and the UK Biobank to identify phenotypic and genetic patterns in parents associated with neurodevelopmental disease risk in children. We identified correlations between six phenotypes in parents and children, including correlations of clinical diagnoses such as obsessive-compulsive disorder (R=0.31-0.

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Adult-onset cerebellar ataxias are a group of neurodegenerative conditions that challenge both genetic discovery and molecular diagnosis. In this study, we identified an intronic (GAA) repeat expansion in fibroblast growth factor 14 (FGF14). Genetic analysis of 95 Australian individuals with adult-onset ataxia identified four (4.

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Aim: To report response to first treatment in infants with infantile spasms (IS), including incremental benefit of prednisolone 60 mg/day and vigabatrin following prednisolone 40 mg/day failure in infants commenced on the United Kingdom Infantile Spasms Study (UKISS) treatment sequence.

Methods: In this retrospective analysis, we compared effectiveness of prednisolone, vigabatrin and nonstandard treatments as first treatment for IS. In infants who commenced the UKISS treatment sequence, we evaluated response to each step.

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