The movement disorder spectrum of SCA21 (ATX-TMEM240): 3 novel families and systematic review of the literature.

@article{Traschtz2019TheMD,
  title={The movement disorder spectrum of SCA21 (ATX-TMEM240): 3 novel families and systematic review of the literature.},
  author={Andreas Trasch{\"u}tz and Judith van Gaalen and Mayke Oosterloo and Maaike Vreeburg and Erik Jan Kamsteeg and Natalie Deininger and Olaf Riess and Matthias Reimold and Tobias B Haack and Ludger Sch{\"o}ls and Bart P.C. Van de Warrenburg and Matthis Synofzik},
  journal={Parkinsonism \& related disorders},
  year={2019},
  volume={62},
  pages={
          215-220
        }
}
The Neurodevelopmental and Motor Phenotype of SCA21 (ATX-TMEM240)
TLDR
It is identified that the manifestation of neurodevelopmental disorders is a key feature of SCA21 and may precede the presence of motor abnormalities, and the coexistence of ataxia and neuro developmental disorders in these subjects suggests a role for spinocerebellar pathways in both outcomes.
On Spinocerebellar Ataxia 21 as a Mimicker of Cerebral Palsy
TLDR
The notion that SCA21 is a neurodevelopmental syndrome and a mimicker of ataxic CP is supported, as both patients presented with early-onset ataxia and exhibited mild parkinsonian features.
NGS in Hereditary Ataxia: When Rare Becomes Frequent
TLDR
A targeted resequencing panel in a large and highly heterogeneous cohort of 377 patients with a clinical diagnosis of HA, but no molecular diagnosis on routine genetic tests obtained a positive result in 33.2% of the patients, significantly higher than those reported in similar studies employing TRP and in line with those performed using exome sequencing.
Clinical and neuroimaging phenotypes of genetic parkinsonism from infancy to adolescence.
TLDR
The relevant literature of genetic parkinsonism with ≤21 years onset is examined, extracting data on associated movement disorders as well as other neurological and imaging features, to delineate syndromic patterns associated with early-onset parkinsonist cases.
A next generation sequencing‐based analysis of a large cohort of ataxic patients refines the clinical spectrum associated with spinocerebellar ataxia 21
TLDR
Clinical and molecular findings in five additional SCA21 patients from four unrelated families, diagnosed through a multicentre next generation sequencing‐based molecular screening project on a large cohort of patients with degenerative and congenital ataxias are described.
Spinocerebellar ataxia type 21 (TMEM240) with tremor and dystonia
TLDR
A NGS-based analysis on a large cohort of ataxic patients refines the clinical spectrum associated with SCA21, and presents four new families withSCA21 of Italian and Libyan origin discussing the wide phenotypic diversity of this disease.
The TMEM240 Protein, Mutated in SCA21, Is Expressed in Purkinje Cells and Synaptic Terminals
TLDR
Data suggest that TMEM240 may be involved in the organization of the cerebellar network, particularly in synaptic inputs converging on Purkinje cells.
The Geographic Diversity of Spinocerebellar Ataxias (SCAs) in the Americas: A Systematic Review
TLDR
The frequency and presentation of each of the most common forms of spinocerebellar ataxias varies widely and this diversity is particularly dynamic given additional social, demographic, and cultural characteristics.
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TLDR
Sanger sequencing was used to detect mutations in exons of TMEM240 in 340 unrelated probands with spinocerebellar ataxia for whom commonly known causative mutations have been excluded and a de novo missense mutation was identified in one sporadic SCA patient.
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TLDR
The first Japanese family with SCA21 is reported, in which all affected members examined carried a heterozygous c.509C > T:p.Pro170Leu variant in TMEM240, which summarized as a slowly progressive ataxia of young-adult onset associated with various degree of psychomotor retardation or cognitive impairment.
TMEM240 mutations cause spinocerebellar ataxia 21 with mental retardation and severe cognitive impairment.
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Reversible inactivation of neurons in the vicinity of identified short‐lead burst neurons produced dramatic reductions in the speed of saccades to horizontal target displacements and microstimulation failed to noticeably slow head movements when stimulation was applied during gaze shifts, suggesting that signals relayed to motoneurons innervating the neck muscles are not inhibited by the omnipause neurons.
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