1. Phenotypic characterization of KCTD3-related developmental epileptic encephalopathy.
- Author
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Faqeih EA, Almannai M, Saleh MM, AlWadei AH, Samman MM, and Alkuraya FS
- Subjects
- Alleles, Cerebellum abnormalities, Cerebellum diagnostic imaging, Cerebellum pathology, Child, Child, Preschool, Dandy-Walker Syndrome diagnostic imaging, Dandy-Walker Syndrome pathology, Female, Genetic Predisposition to Disease, Humans, Hydrocephalus diagnostic imaging, Hydrocephalus pathology, Infant, Loss of Function Mutation genetics, Male, Mutation, Phenotype, Spasms, Infantile diagnostic imaging, Spasms, Infantile pathology, Dandy-Walker Syndrome genetics, Potassium Channels genetics, Spasms, Infantile genetics, Exome Sequencing
- Abstract
The association between KCTD3 gene and neurogenetic disorders has only been published recently. In this report, we describe the clinical phenotype associated with 2 pathogenic variants in KCTD3 gene. Seven individuals (including one set of monozygotic twin) from 4 consanguineous families presented with developmental epileptic encephalopathy, global developmental delay, central hypotonia, progressive peripheral hypertonia, and variable dysmorphic facial features. Posterior fossa abnormalities (ranging from Dandy-Walker malformation to isolated hypoplasia of the cerebellar vermis) were consistently observed in addition to other variable neuroradiological abnormalities such as hydrocephalus and abnormal brain myelination. One patient also had a multicystic kidney. Whole exome sequencing revealed 2 probably pathogenic homozygous variants in KCTD3 gene that fully segregated with the disease. KCTD3 gene belongs to a family of accessory subunits that regulate the biophysical properties of ion channels, and is highly expressed in the kidney and brain. In this largest series to date on KCTD3-mutated patients, we show that biallelic loss of function mutations in KCTD3 lead to a consistent phenotype of developmental epileptic encephalopathy and abnormal cerebellum on brain imaging., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2018
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