An autosomal dominant disorder characterized by global developmental delay apparent in the first six months of life, followed by onset of seizures between 21 months and 4 years. Disease features include moderate-to-severe intellectual disability, poor speech, delayed walking, and ataxia. The disease is EFO_0010566 (intellectual developmental disorder 60 with seizures). Also known as: intellectual disability, autosomal dominant 60, with seizures.