Dataset Information

A SEPSECS mutation in a 23-year-old woman with microcephaly and progressive cerebellar ataxia.

ABSTRACT: Mutations in the SEPSECS gene are associated with pontocerebellar hypoplasia type 2D. Pontocerebellar hypoplasia (PCH) is a heterogeneous group of rare autosomal recessive neurodegenerative disorders, mainly affecting pons and cerebellum. Patients have severe motor and cognitive impairments and often die during infancy. Here, we report a 23-year-old woman with slowly progressive cerebellar ataxia and cognitive impairment, in whom a homozygous missense mutation in the SEPSECS gene (c.1321G>A; p.Gly441Arg) was identified with whole exome sequencing. Our findings underline that defects in selenoprotein synthesis can also result in milder cerebellar atrophy presenting at a later age.

SUBMITTER: van Dijk T

PROVIDER: S-EPMC6133186 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A SEPSECS mutation in a 23-year-old woman with microcephaly and progressive cerebellar ataxia.

van Dijk Tessa T Vermeij Jan-Dirk JD van Koningsbruggen Silvana S Lakeman Phillis P Baas Frank F Poll-The Bwee Tien BT

Journal of inherited metabolic disease 20180220 5

Mutations in the SEPSECS gene are associated with pontocerebellar hypoplasia type 2D. Pontocerebellar hypoplasia (PCH) is a heterogeneous group of rare autosomal recessive neurodegenerative disorders, mainly affecting pons and cerebellum. Patients have severe motor and cognitive impairments and often die during infancy. Here, we report a 23-year-old woman with slowly progressive cerebellar ataxia and cognitive impairment, in whom a homozygous missense mutation in the SEPSECS gene (c.1321G>A; p.G ...[more]

PMID: 29464431

Similar Datasets

Project description:Spinocerebellar ataxia type 23 (SCA23) is a late-onset neurodegenerative disorder characterized by slowly progressive gait and limb ataxia, for which there is no therapy available. It is caused by pathogenic variants in PDYN, which encodes prodynorphin (PDYN). PDYN is processed into the opioid peptides α-neoendorphin and dynorphins (Dyn) A and B; inhibitory neurotransmitters that function in pain signaling, stress-induced responses and addiction. Variants causing SCA23 mostly affect Dyn A, leading to loss of secondary structure and increased peptide stability. PDYNR212W mice express human PDYN containing the SCA23 variant p.R212W. These mice show progressive motor deficits from 3 months of age, climbing fiber (CF) deficits from 3 months of age, and Purkinje cell (PC) loss from 12 months of age. A mouse model for SCA1 showed similar CF deficits, and a recent study found additional developmental abnormalities, namely increased GABAergic interneuron connectivity and non-cell autonomous disruption of PC function. As SCA23 mice show a similar pathology to SCA1 mice in adulthood, we hypothesized that SCA23 may also follow SCA1 pathology during development. Examining PDYNR212W cerebella during development, we uncovered developmental deficits from 2 weeks of age, namely a reduced number of GABAergic synapses on PC soma, possibly leading to the observed delay in early phase CF elimination between 2 and 3 weeks of age. Furthermore, CFs did not reach terminal height, leaving proximal PC dendrites open to be occupied by parallel fibers (PFs). The observed increase in vGlut1 protein-a marker for PF-PC synapses-indicates that PFs indeed take over CF territory and have increased connectivity with PCs. Additionally, we detected altered expression of several critical Ca2+ channel subunits, potentially contributing to altered Ca2+ transients in PDYNR212W cerebella. These findings indicate that developmental abnormalities contribute to the SCA23 pathology and uncover a developmental role for PDYN in the cerebellum.

Dataset Information

A SEPSECS mutation in a 23-year-old woman with microcephaly and progressive cerebellar ataxia.

Publications

A SEPSECS mutation in a 23-year-old woman with microcephaly and progressive cerebellar ataxia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets