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GTR Home > Conditions/Phenotypes > Developmental and epileptic encephalopathy 89

Summary

Developmental and epileptic encephalopathy-89 (DEE89) is a severe autosomal recessive disorder characterized by profound global developmental delay with impaired intellectual development, absent speech, inability to sit or walk due to axial hypotonia and spastic quadriparesis, and onset of seizures in the first days or months of life. EEG shows suppression-burst pattern or hypsarrhythmia, consistent with DEE or a clinical diagnosis of West syndrome. More variable features include joint contractures with foot deformities, dysmorphic facial features with cleft palate, and omphalocele. Affected individuals have poor motor skills, poor eye contact, and lack of language development; some die in infancy or early childhood. Brain imaging may be normal or show nonspecific abnormalities (summary by Chatron et al., 2020). [from OMIM]

Available tests

8 tests are in the database for this condition.

Genes See tests for all associated and related genes

  • Also known as: CPSQ1, DEE89, GAD, SCP, GAD1
    Summary: glutamate decarboxylase 1

Clinical features

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