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Succinic semialdehyde dehydrogenase deficiency

Other Names for this Disease
  • 4-hydroxybutyric aciduria
  • GABA metabolic defect
  • Gamma-hydroxybutyricaciduria
  • SSADH deficiency
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What causes succinic semialdehyde dehydrogenase deficiency?

Succinic semialdehyde dehydrogenase deficiency (SSADH) is caused by mutations in the ALDH5A1 gene. This gene provides instructions for producing the succinic semialdehyde dehydrogenase enzyme which is involved in the breakdown of a chemical that transmits signals in the brain (neurotransmitter) called gamma-amino butyric acid (GABA). The primary role of GABA is to prevent the brain from being overloaded with too many signals. A shortage (deficiency) of succinic semialdehyde dehydrogenase leads to an increase in the amount of GABA and a related molecule called gamma-hydroxybutyrate (GHB) in the body, particularly the brain and spinal cord (central nervous system). It is unclear how an increase in GABA and GHB causes developmental delay, seizures, and other signs and symptoms of succinic semialdehyde dehydrogenase deficiency.[1]
Last updated: 9/25/2013

  1. Succinic semialdehyde dehydrogenase deficiency. Genetics Home Reference. June 2008; Accessed 9/25/2013.