Publications by authors named "Louisa Kalsner"

The shift to a genotype-first approach in genetic diagnostics has revolutionized our understanding of neurodevelopmental disorders, expanding both their molecular and phenotypic spectra. Kleefstra syndrome (KLEFS1) is caused by EHMT1 haploinsufficiency and exhibits broad clinical manifestations. EHMT1 encodes euchromatic histone methyltransferase-1-a pivotal component of the epigenetic machinery.

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Article Synopsis
  • - The p21-activated kinase (PAK) family regulates important cellular processes, including cell adhesion, movement, growth, and programmed cell death, with PAK2 specifically playing a role in apoptosis and angiogenesis.
  • - A new missense variant, p.(Thr406Met), was discovered in a newborn with symptoms of Knobloch syndrome, alongside another variant, p.(Asp425Asn), both leading to significantly reduced PAK2 protein activity.
  • - These findings suggest that deficiencies in PAK2 are linked to a second form of Knobloch syndrome, known as KNO2, supporting previous research on related PAK2 variants.
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P21-activated kinase 2 (PAK2) is a serine/threonine kinase essential for a variety of cellular processes including signal transduction, cellular survival, proliferation, and migration. A recent report proposed monoallelic variants cause Knobloch syndrome type 2 (KNO2)-a developmental disorder primarily characterized by ocular anomalies. Here, we identified a novel heterozygous missense variant in NM_002577.

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The aim of this review was to discuss bioethics in prenatal diagnosis and health care after recent legislative and judicial changes affecting reproductive rights, such as the repeal of 'Roe v. Wade' in the United States. We recognize that abortion involves particular moralities that are not universal or shared by all cultures, groups, and individuals.

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  • The study reports on seven patients with Marbach-Schaaf neurodevelopmental syndrome, all sharing the same genetic variant in the PRKAR1B gene, which affects their neurological development.
  • Key symptoms include global developmental delay, reduced pain sensitivity, and some behavioral issues, with only one patient formally diagnosed with autism spectrum disorder (ASD), suggesting a lower prevalence of ASD in this syndrome than previously thought.
  • The findings indicate that PRKAR1B plays a significant role in neuron function and highlights the need to explore molecular mechanisms to better understand the disorder's diverse clinical presentations.
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Deletion 1p36 (del1p36) syndrome is the most common human disorder resulting from a terminal autosomal deletion. This condition is molecularly and clinically heterogeneous. Deletions involving two non-overlapping regions, known as the distal (telomeric) and proximal (centromeric) critical regions, are sufficient to cause the majority of the recurrent clinical features, although with different facial features and dysmorphisms.

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Thousand and one amino-acid kinase 1 (TAOK1) is a MAP3K protein kinase, regulating different mitogen-activated protein kinase pathways, thereby modulating a multitude of processes in the cell. Given the recent finding of TAOK1 involvement in neurodevelopmental disorders (NDDs), we investigated the role of TAOK1 in neuronal function and collected a cohort of 23 individuals with mostly de novo variants in TAOK1 to further define the associated NDD. Here, we provide evidence for an important role for TAOK1 in neuronal function, showing that altered TAOK1 expression levels in the embryonic mouse brain affect neural migration in vivo, as well as neuronal maturation in vitro.

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We describe five members of a consanguineous Pakistani family (Family I) plus two affected children from families of different ethnic origins presenting with neurodevelopmental disorders with overlapping features. All affected individuals from families have intellectual disability (ID), ranging from mild to profound, and reduced motor and cognitive skills plus variable features including short stature, microcephaly, developmental delay, hypotonia, dysarthria, deafness, visual problems, enuresis, encopresis, behavioural anomalies, delayed pubertal onset and facial dysmorphism. We first mapped the disease locus in the large family (Family I), and by exome sequencing identified homozygous ZNF407 c.

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The Jumonji domain containing 1C (JMJD1C) gene encodes the Jumonji domain-containing protein 1C (JMJD1C) and is a member of the jmJC domain-containing protein family involved in histone demethylation that is expressed in the brain. We report seven, unrelated patients with developmental delays or intellectual disability and heterozygous, de novo sequence variants in JMJD1C. All patients had developmental delays, but there were no consistent additional findings.

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Developmental delay and intellectual disability (DD and ID) are heterogeneous phenotypes that arise in many rare monogenic disorders. Because of this rarity, developing cohorts with enough individuals to robustly identify disease-associated genes is challenging. Social-media platforms that facilitate data sharing among sequencing labs can help to address this challenge.

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Purpose: To define the clinical characteristics of patients with variants in TCF20, we describe 27 patients, 26 of whom were identified via exome sequencing. We compare detailed clinical data with 17 previously reported patients.

Methods: Patients were ascertained through molecular testing laboratories performing exome sequencing (and other testing) with orthogonal confirmation; collaborating referring clinicians provided detailed clinical information.

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Article Synopsis
  • * A study of 72 participants provided detailed analysis of SAS, going beyond previous limited reports to identify key clinical and genetic characteristics.
  • * Major findings highlight severe speech delays, palate and dental abnormalities, and behavioral issues, which can aid healthcare providers in diagnosis and management, offering better support for affected families.
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Background: Genetic testing of children with autism spectrum disorder (ASD) is now standard in the clinical setting, with American College of Medical Genetics and Genomics (ACMGG) guidelines recommending microarray for all children, fragile X testing for boys and additional gene sequencing, including PTEN and MECP2, in appropriate patients. Increasingly, testing utilizing high throughput sequencing, including gene panels and whole exome sequencing, are offered as well.

Methods: We performed genetic testing including microarray, fragile X testing and targeted gene panel, consistently sequencing 161 genes associated with ASD risk, in a clinical population of 100 well characterized children with ASD.

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Three distinct neurodevelopmental disorders arise primarily from deletions or duplications that occur at the 15q11-q13 locus: Prader-Willi syndrome, Angelman syndrome, and 15q11-q13 duplication syndrome. Each of these disorders results from the loss of function or overexpression of at least 1 imprinted gene. This article discusses the clinical background, genetic cause, diagnostic strategy, and management of each of these 3 disorders.

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