Publications by authors named "Helena G Karstensen"

Objective: Monoallelic variants in the transient receptor potential melastatin-related type 3 gene (TRPM3) have been associated with neurodevelopmental manifestations, but knowledge on the clinical manifestations and treatment options is limited. We characterized the clinical spectrum, highlighting particularly the epilepsy phenotype, and the effect of treatments.

Methods: We analyzed retrospectively the phenotypes and genotypes of 43 individuals with TRPM3 variants, acquired from GeneMatcher and collaborations (n = 21), and through a systematic literature search (n = 22).

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Background: Vascular anomalies caused by somatic (postzygotic) variants are clinically and genetically heterogeneous diseases with overlapping or distinct entities. The genetic knowledge in this field is rapidly growing, and genetic testing is now part of the diagnostic workup alongside the clinical, radiological and histopathological data. Nonetheless, access to genetic testing is still limited, and there is significant heterogeneity across the approaches used by the diagnostic laboratories, with direct consequences on test sensitivity and accuracy.

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Genetic conditions are often familial, but not all relatives receive counseling from the same institution. It is therefore necessary to ensure consistency in variant interpretation, counseling practices, and clinical follow up across health care providers. Furthermore, as new possibilities for gene-specific treatments emerge and whole genome sequencing becomes more widely available, efficient data handling and knowledge sharing between clinical laboratory geneticists and medical specialists in clinical genetics are increasingly important.

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is a mitochondrial protein involved in mitochondrial dynamics. Recently, bi-allelic variants have been identified as a pathogenic cause in a spectrum of neurological syndromes. We report a novel homozygous variant in two siblings, originating from Iraq.

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Article Synopsis
  • Protein lipoylation is crucial for cell metabolism, with the H-protein (GCSH) playing a key role in this process for important enzymes and one-carbon metabolism.
  • A study of six patients with pathogenic variants in GCSH showed a range of clinical issues, from severe neonatal encephalopathy to milder developmental delays and movement disorders.
  • Functional analyses revealed that most mutations led to reduced mitochondrial activity and metabolic deficiencies, highlighting the importance of understanding these variants to guide treatment options.
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Mohr-Tranebjærg syndrome is an X-linked syndrome characterized by sensorineural hearing impairment in childhood, followed by progressive neurodegeneration leading to a broad phenotypic spectrum. Genetically MTS is caused by pathogenic variants in the TIMM8A gene, including gene deletions and larger contiguous gene deletions. Some of the latter involve the neighboring gene BTK, resulting in agammaglobulinemia.

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Mosaic PIK3R1 variants have recently been demonstrated in patients with complex vascular malformations and overgrowth in a syndrome resembling PIK3CA-related overgrowth syndrome (PROS). The PIK3CA-inhibitor, alpelisib, seems to be a promising treatment option for PROS patients. We describe a young boy with overgrowth and a pathogenic mosaic variant in PIK3R1; c.

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TRPM3 encodes a transient receptor potential cation channel of the melastatin family, expressed in the central nervous system and in peripheral sensory neurons of the dorsal root ganglia. The recurrent substitution in TRPM3: c.2509G>A, p.

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Article Synopsis
  • * Researchers identified 32 individuals with microcephaly, neurodevelopmental issues, and other neurological symptoms due to mutations in NARS1, revealing reduced levels of NARS1 mRNA and enzyme activity in affected cells.
  • * The study suggests that these mutations lead to neurodevelopmental diseases through mechanisms like toxic gain-of-function for new mutations and partial loss-of-function for recessive mutations.
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Biallelic variants in HARS2 have been associated with Perrault syndrome, characterized by sensorineural hearing impairment and premature ovarian insufficiency. Here we report three novel families, compound heterozygous for missense variants in HARS2 identified by next-generation sequencing, namely c.172A > G (p.

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The human sense of smell is closely associated with morphological differences of the fronto-limbic system, specifically the piriform cortex and medial orbitofrontal cortex (mOFC). Still it is unclear whether cortical volume in the core olfactory areas and connected brain regions are shaped differently in individuals who suffer from lifelong olfactory deprivation relative to healthy normosmic individuals. To address this question, we examined if regional variations in gray matter volume were associated with smell ability in seventeen individuals with isolated congenital olfactory impairment (COI) matched with sixteen normosmic controls.

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Background: Usher syndrome (USH) is a genetically heterogeneous deafness-blindness syndrome, divided into three clinical subtypes: USH1, USH2 and USH3.

Methods: Mutations in 21 out of 26 investigated Danish unrelated individuals with USH were identified, using a combination of molecular diagnostic methods.

Results: Before Next Generation Sequencing (NGS) became available mutations in nine individuals (1 USH1, 7 USH2, 1 USH3) were identified by Sanger sequencing of , or or by Arrayed Primer EXtension (APEX) method.

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Olfaction and gustation contribute both to the appreciation of food flavours. Although acquired loss of smell has profound consequences on the pleasure of eating, food habits and body weight, less is known about the impact of congenital olfactory impairment on gustatory processing. Here we examined taste identification accuracy and its neural correlates using functional magnetic resonance imaging (fMRI) in 12 congenitally olfactory impaired individuals and 8 normosmic controls.

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