Publications by authors named "Paucar M"

Objectives: Since the discovery of biallelic pentanucleotide expansions in as the cause of cerebellar ataxia, neuropathy, vestibular areflexia syndrome, a wide and growing clinical spectrum has emerged. In this article, we report a man with acute vestibular syndrome that likely unmasked a -spectrum disorder.

Methods: Detailed clinical evaluation, neuroimaging, nerve conduction studies, evaluation of vestibular function, and short-read whole-genome sequencing and targeted long-read adaptive sequencing were performed.

View Article and Find Full Text PDF

Objective: Pathogenic variants in B-cell receptor-associated protein (BCAP31) are associated with X-linked, deafness, dystonia and cerebral hypomyelination (DDCH) syndrome. DDCH is congenital and non-progressive, featuring severe intellectual disability (ID), variable dysmorphism, and sometimes associated with shortened survival. BCAP31 encodes one of the most abundant chaperones, with several functions including acting as a negative regulator of endoplasmic reticulum (ER) calcium ion (Ca) concentration.

View Article and Find Full Text PDF

Background: The identification of a heterozygous exonic GGC repeat expansion in ZFHX3 underlying spinocerebellar ataxia type 4 (SCA4) has solved a 25-year diagnostic conundrum. We used adaptive long-read sequencing to decipher the pathogenic expansion in the index Utah family and an unrelated family from Iowa of Swedish ancestry. Contemporaneous to our discovery, other groups identified the same repeat expansion in affected individuals from Utah, Sweden, and Germany, highlighting the current pivotal time for detection of novel repeat expansion disorders.

View Article and Find Full Text PDF

Mutations in the gene encoding the alpha3 Na+/K+-ATPase isoform (ATP1A3) lead to movement disorders that manifest with dystonia, a common neurological symptom with many different origins, but for which the underlying molecular mechanisms remain poorly understood. We have generated an ATP1A3 mutant mouse that displays motor impairments and a hyperexcitable motor phenotype compatible with dystonia. We show that neurons harboring this mutation are compromised in their ability to extrude raised levels of intracellular sodium, highlighting a profound deficit in neuronal sodium homeostasis.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on neuroacanthocytosis diseases, specifically a patient presenting with hyperkinetic symptoms linked to genetic variants affecting erythrocyte deformability and acanthocyte presence in blood.
  • A comprehensive assessment was conducted using various methods, including ektacytometry, clinical evaluations, and genetic analysis to understand the patient's condition better and identify potential variants.
  • The findings indicated reduced erythrocyte deformability in the patient with neuroacanthocytosis and revealed a unique ektacytometry pattern that differentiates it from other forms of acanthocytosis.
View Article and Find Full Text PDF

XK disease is a very rare, multi-system disease, which can present with a wide spectrum of symptoms. This disorder can also be identified pre-symptomatically with the incidental detection of serological abnormalities when typing erythrocytes in peripheral blood, or on other routine laboratory testing. Increasing awareness of this disorder and improved access to genetic testing are resulting in increasing identification of affected patients and families.

View Article and Find Full Text PDF
Article Synopsis
  • Spinocerebellar ataxia 4 (SCA4) is an adult-onset neurodegenerative disorder linked to chromosome 16q22.1, characterized by ataxia, polyneuropathy, and various neurological symptoms that were previously poorly understood.* -
  • A research study on three Swedish families employed various diagnostic methods, including genetic testing and neuroimaging, revealing new features such as dysautonomia, motor neuron involvement, and significant brain atrophy.* -
  • The study identified a novel genetic mutation, a GGC expansion in the ZFHX3 gene, as the cause of SCA4, expanding its clinical profile to include symptoms like dysautonomia and other neuromuscular
View Article and Find Full Text PDF

Introduction: Brain calcifications are frequent findings on imaging. In a small proportion of cases, these calcifications are associated with pathogenic gene variants, hence termed primary familial brain calcification (PFBC). The clinical penetrance is incomplete and phenotypic variability is substantial.

View Article and Find Full Text PDF

Introduction: Huntington's disease (HD) is a hereditary neurodegenerative disease, currently lacking disease-modifying treatments. Biomarkers are needed for objective assessment of disease progression. Evidence supports both complex protein aggregation and astrocyte activation in HD.

View Article and Find Full Text PDF
Article Synopsis
  • The study characterizes a large Estonian family with five generations affected by spastic paraplegia linked to a new variant in the receptor expression-enhancing protein-1 gene.
  • Comprehensive assessments including clinical evaluations, imaging, and genetic testing were conducted on affected individuals to investigate the genetic basis and symptoms.
  • Results show variability in symptoms and disease manifestations among family members, indicating that the severity of the spastic paraplegia may not differ significantly between splice variants and conventional variants, with underlying factors still unclear.
View Article and Find Full Text PDF

Ataxia telangiectasia (A-T), caused by biallelic variants in the gene, is a multisystemic and severe syndrome characterized by progressive ataxia, telangiectasia, hyperkinesia, immunodeficiency, increased risk of malignancy, and typically death before the age of 30. In this retrospective study we describe the phenotype of 14 pediatric and adult A-T patients evaluated at the Karolinska University Hospital in Sweden during the last 12 years. Most of the patients in this cohort were severely affected by ataxia and wheelchair use started at a median age of 9 years.

View Article and Find Full Text PDF

Nitrous oxide abuse may cause functional cobalamin deficiency and subsequent damage to the peripheral nerves, the spinal cord, and the brain, a symptom complex best described by the term cobalamin neuropathy. Here, we report a case of cobalamin neuropathy with uncommon cerebral symptomatology following nitrous oxide intoxication and contextualize the symptomatology. A 22-year-old male with a history of mixed drug dependency presented at the emergency room after inhaling six 615 g cylinders, equal to ~1800 L, of nitrous oxide daily for two weeks.

View Article and Find Full Text PDF
Article Synopsis
  • There are rare mitochondrial disorders linked to biallelic variations that cause kidney failure, tremors, hearing loss, seizures, and intellectual disability, with only two prior studies noted.
  • A case study of a man showed symptoms like ataxia, kidney failure, and hearing loss, revealing a novel variant through whole genome sequencing.
  • The findings highlighted significant mitochondrial abnormalities, underpinning the connection between the newly identified variant and a slowly progressive form of cerebellar ataxia, contributing to the understanding of this genetic condition.
View Article and Find Full Text PDF

Background: Niemann-Pick disease type C (NPC) is a rare, fatal, pan-ethnic, autosomal recessive lysosomal storage disease characterized by progressive major organ failure and neurodegeneration. Preclinical studies confirmed a critical role of systemically administered hydroxypropyl-β-cyclodextrin (HP-β-CD; Trappsol Cyclo™) in cholesterol metabolism and homeostasis in peripheral tissues of the body, including the liver, and in the central nervous system (CNS). Herein, the pharmacokinetics (PK), safety, and efficacy of HP-β-CD, and biomarkers of NPC were assessed in pediatric and adult patients with NPC1.

View Article and Find Full Text PDF

Sustainability may be at risk in a population that has altered health, according to Sustainable Development Goal 3 (SDG 3): Health and well-being. The ongoing conflict between Russia and Ukraine could jeopardize SDG 3, specifically the mental health of the population. The present study sought to determine the association between severe anxiety, depression and stress in population of 13 Latin American countries according to fear about the war conflict.

View Article and Find Full Text PDF

A five-year-old girl presented with headache attacks, clumsiness, and a history of transient gait disturbances. She and her father, mother, twin sister, and brother underwent neurological evaluation, neuroimaging, and exome sequencing covering 357 genes associated with movement disorders. Sequencing revealed the new variant c.

View Article and Find Full Text PDF
Article Synopsis
  • - The study aimed to screen for Huntington disease phenocopies in a Swedish group of 73 DNA samples that tested negative for Huntington's disease.
  • - Genetic analyses revealed two patients with spinocerebellar ataxia type 17 and one with an inherited prion disease, along with two cases of myoclonic dystonia and benign hereditary chorea, while no cases of other specific disorders were found.
  • - The findings support previous research and indicate that there may be undiscovered genes contributing to the development of Huntington disease-like symptoms.
View Article and Find Full Text PDF
Article Synopsis
  • Neuromuscular disorders (NMDs) have various causes, and getting a genetic diagnosis is essential for personalized treatment.
  • The study analyzed 861 patients using genome sequencing to identify genetic variants associated with NMDs, finding that 27% had pathogenic variants, with one-third involving short tandem repeats (STRs) and structural variants (SVs).
  • The findings suggest that a comprehensive genome-wide analysis, especially for children with vague symptoms, is more effective than just focusing on specific disease-related genes, emphasizing the need to include STR and SV analyses in NMD diagnostics.
View Article and Find Full Text PDF
Article Synopsis
  • Individuals with intellectual disabilities (ID) and neurodevelopmental disorders (NDD) are assessed using various genetic testing methods, including genome sequencing (GS) and chromosomal microarrays (CMA).
  • A study comparing three diagnostic approaches found that GS as the first test had a 35% diagnostic yield, while GS as a secondary test yielded 26%, and CMA/FMR1 yielded only 11%.
  • The research suggests that GS should be the preferred first-line genetic test for ID/NDD due to its higher effectiveness, lower costs, and potential to provide earlier diagnoses.
View Article and Find Full Text PDF

Objectives: Sporadic variants in ataxia genes may mimic cerebral palsy (CP). Spinocerebellar ataxia 21 (SCA21), a very rare autosomal dominant disease, was discovered to be associated with variants in the transmembrane protein 240 () gene in 2014. In this report, we present 2 patients with sporadic SCA21, one of them diagnosed with ataxic CP.

View Article and Find Full Text PDF

Background: COVID-19 has caused profound socio-economic changes worldwide. However, internationally comparative data regarding the financial impact on individuals is sparse. Therefore, we conducted a survey of the financial impact of the pandemic on individuals, using an international cohort that has been well-characterized prior to the pandemic.

View Article and Find Full Text PDF