Case series; NUS1 deletions cause a progressive myoclonic epilepsy with ataxia.

Purpose: Mutations in NUS1 cause a neurological congenital glycosylation disorder which encompasses a spectrum from developmental encephalopathy to musculoskeletal, hearing, and visual abnormalities. Pathogenic variants include both point mutations and genomic deletions. We report an adult phenotype of progressive myoclonus epilepsy (PME) and a review of cases with a complete or partial deletion of NUS1.