Table 1.

Phenotypic Details of Individuals with the Recurrent AP2M1 c.508C > T (p.Arg170Trp) Variant

	Proband ID
	Individual 1	Individual 2	Individual 3	Individual 4
Age and sex	7 years, f	15 years, f	4 years, f	8 years, f
Development	globally delayed	globally delayed	globally delayed	globally delayed
Age at seizure onset	1 year, 9 months	1 year, 3 months	3 years	4 years
Seizure types	atypical absence; myoclonic atonic; absence with eyelid myoclonia	atonic; atypical absence; absence with eyelid myoclonia	atonic; bilateral tonic-clonic	focal impaired-awareness
Seizure outcome	drug-responsive	drug-resistant	drug-resistant	partially responsive
Intellectual disability (severity)	moderate	moderate	severe	severe
Autism spectrum disorder	absent	absent (aggressive and self-harming behaviors)	present	present
Ataxia	truncal and gait ataxia	absent	gait ataxia only	truncal and gait ataxia
Other exam findings	hypotonia	hypotonia	hypotonia; chorea and myoclonus; a prominent maxilla and a thin upper lip	hypotonia; tremor; long, thin hands and feet
MRI findings	parieto-occipital white matter abnormalities	normal	normal	normal
EEG findings	generalized polyspike-wave discharges	3–4 Hz generalized spike-wave discharges	generalized spike-wave discharges	multifocal epileptiform activity

Abbreviations are as follows: MRI = magnetic resonance imaging and EEG = electroencephalogram.