The main clinical features of individuals with an ARID1A mutation can differ from mild intellectual disability to a severe intellectual disability with internal complications (Kosho 2014). Besides developmental delay other features of CSS, which are not present in all ARID1A patients, are intellectual disability, agenesis of the corpus callosum, speech delay, feeding difficulties, absent nails of the fifth finger and toe, excessive hair growth, coarse facial features and hypotonia.
ARID1A