Patient 1 is a 5-year-old girl, who was observed to have severe hypotonia in her infancy and developmental delay. She was incapable of lifting her head when she was 7-month-old as well as was incapable of sitting by herself and had trouble imitating speech or actions when she was 1-year-old. By the age of 14 months, she was found to lack the ability to maintain eye contact and displayed head-shaking, hand-clapping and hand-wringing as well as bruxism. While she exhibited purposeful hand use, she presented recurrent, febrile or non-febrile, generalized tonic-clonic seizures at the age of 18 months. After receiving treatment with Levetiracetam (LEV) at 20 months, she achieved seizure-free status at the age of 2 years. At the age of 18 months and 2 years, the findings of her EEG tests revealed spike-and-slow waves with bilateral temporal involvement. Her MRI findings at the age of 14 months indicated a widened subarachnoid space ().
Patient 7 is a female who is currently 2 years 5 months old. She experienced severe hypotonia at infancy and was observed to have developmental delay. She was incapable of both lifting her head at the age of 7 months and sitting independently at the age of 2 years; she was also unable to walk independently, demonstrated no non-verbal communication skills, and was unable to imitate or babble. Poor eye contact as well as head-shaking and hand-clapping behavior were observed at the age of 1 year. She did not display purposeful hand usage. She did not experience seizure. EEG test conducted at the age of 2 years revealed 2–3 Hz sharp-slow waves at the left parietal-occipital region. MRI scans taken at the age of 14 months showed malformation of the corpus callosum, delayed myelination and leukomalacia in the periventricular region ().