| Main clinical features
|
Rett‐like phenotype accompanied by areflexia
global developmental delay, severe to profound intellectual disability, muscle weakness and abnormal tone, autistic features, with hand stereotypy, episodes of laughing and/or screaming, and bruxism, behavioral abnormalities, and variable dysmorphisms (low-set ears, hypotelorism, and frontal bossing)
global developmental delay with severe to profound intellectual disability; the majority were non-verbal and non-ambulatory
brain imaging, conducted in both infancy and childhood, demonstrated findings ranging from normal to mild brain atrophy with white matter abnormalities |