Aromatic L-amino acid decarboxylase (AADC) deficiency (AADCD) is a rare disease that typically affects infants and is inherited in an autosomal recessive pattern. The affected infants have mutations in the DDC gene which encodes AADC enzyme leading to the deficient synthesis of dopamine (DA) and serotonin (5-HT). Both neurotransmitters are critical for the normal function of the central nervous system.

Severe delay of the development, hypotonia, movement disorders (oculogyric crisis, dystonia, and hypokinesia), and autonomic symptoms