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Neurodevelopmental disorder with speech impairment and with or without seizures

Synonyms
Neurodevelopmental disorder with variable intellectual disability and speech impairment, with or without seizures

Summary

Neurodevelopmental disorder with speech impairment and with or without seizures (NEDSIS) is a phenotypically heterogeneous neurologic disorder whose severity appears to depend on the functional effect of the CACNA1I mutation. Severely affected individuals present in infancy with profound global developmental delay, hypotonia, delayed or absent walking, absent speech, feeding difficulties, cortical visual impairment, and onset of hyperexcitability and seizures in the first months or years of life. They achieve little or no developmental progress and may be tube-fed. Mutations in these individuals occurred de novo. In contrast, a milder phenotype associated with an inherited mutation has been found in a family with mild to moderate cognitive impairment and mild speech delay, usually without seizures (El Ghaleb et al., 2021). [from OMIM]

Genes See tests for all associated and related genes

  • Also known as: Cav3.3, NEDSIS, ca(v)3.3, CACNA1I
    Summary: calcium voltage-gated channel subunit alpha1 I

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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