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Guanidinoacetate methyltransferase deficiency

Disease definition

Guanidinoacetate methyltransferase (GAMT) deficiency is a creatine deficiency syndrome characterized by global developmental delay/intellectual disability (DD/ID), prominent speech delay, autistic/hyperactive behavioral disorders, seizures, and various types of pyramidal and/or extra-pyramidal manifestations.


Classification level: Disorder
  • Synonym(s):
    • GAMT deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Childhood
  • ICD-10: E72.8
  • OMIM: 612736
  • UMLS: C0574080
  • MeSH: C537622
  • GARD: 2578
  • MedDRA: -

Detailed information


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