Autism spectrum disorder and GABA levels in children with succinic semialdehyde dehydrogenase deficiency

Aim To elucidate the etiological aspects of autism spectrum disorder (ASD) in succinic semialdehyde dehydrogenase deficiency (SSADHD), related to dysregulation of γ‐aminobutyric acid (GABA) and the imbalance of excitatory and inhibitory neurotransmission. Method In this prospective, international study, individuals with SSADHD underwent neuropsychological assessments, as well as biochemical, neurophysiological, and neuroimaging evaluations. Results Of the 29 individuals (17 females) enrolled (median age [IQR] 10 years 5 months [5 years 11 months–18 years 1 month]), 16 were diagnosed with ASD. ASD severity significantly increased with age (r = 0.67, p