Table 1.
The clinical characteristics of patients with FOXG1 deletion/intragenic mutations and FOXG1 duplications.
| Clinical Features | Deletion/Intragenic Mutations of FOXG1 | Duplication of FOXG1 |
|---|---|---|
| Neurodevelopment | Severe global delay | Global delay, but variable severities |
| Speech | Absence or minimal | Delay, but may produce beyond words |
| Ambulation | Typically not acquired | Impaired, but may have ability to walk |
| Social contact | Impaired | Impaired |
| Sleep disorder | Present | Present |
| Visual impairment | High-level visual dysfunctions, strabismus, small optic disc, etc. | +/− |
| Breathing abnormalities | +/− | +/− |
| Movement disorder: Dyskinesia, hyperkinetic movements | Starts from early childhood | +/− |
| Stereotypies | Present | +/− |
| Microcephaly | Typically normal or borderline small at birth, evolving to severe microcephaly in infancy | +/− |
| Brain MRI | Corpus callosum hypogenesis/agenesis; forebrain anomaly; delayed myelination | Typically normal |
| Epilepsy | Onset in early childhood, variable seizure types, often refractory to treatment | Infantile spasms, mostly responsive to adrenocorticotropic hormone (ACTH) |