Diagnosis is based on genetic testing, with the recommended testing approach being Chromosomal Microarray Analysis followed by an Intellectual<unk>  multigene panel or Whole Exome Sequencing. A diagnosis is established following the identification of a heterozygous pathogenic (or likely pathogenic) point mutation of the<unk>  gene (present in approximately 89% of patients), a micro deletion of chromosome 6 incorporating<unk>  (approximately 11% of patients), or a balanced translocation disrupting<unk> . EEG monitoring frequently shows generalized epilepsy, predominantly in the occipital regions. Seizure onset usually occurs around 2 years of age. MRI is usually normal. Seizure types<unk> -related encephalopathy can result in a specific seizure type, characterized by eyelid myoclonia followed by an atonic drop. Reflex seizures are also seen, often triggered by eating and photosensitivity. * Atonic seizures * Eyelid myoclonia * Myoclonic absences * Myoclonic jerks * Tonic-clonic seizures Differential diagnosis * Angelman Syndrome * Autism Spectrum Disorder * Cerebral Palsy * Doose Syndrome * Global Developmental Delay * Infantile Spasms * Jeavons Syndrome * Lennox-Gastaut Syndrome * Pervasive Developmental Disorder * Rett Syndrome * Tuberous Sclerosis * West Syndrome
SYNGAP1-related intellectual disability
SYT1-associated neurodevelopmental disorder
MECP2 duplication syndrome
LMNA-related congenital muscular dystrophy
X-linked intellectual disability
X-linked spinal muscular atrophy type 2
Autosomal recessive spastic ataxia of Charlevoix-Saguenay
Foster Kennedy syndrome