DDC and aromatic L-amino acid decarboxylase deficiency: Aromatic l‐amino acid decarboxylase deficiency (AADC) deficiency (AADCD; OMIM 608643) is a rare autosomal recessive disease because of pathogenic variants of the dopa decarboxylase (DDC gene); subsequent monoamine defect leads to early‐onset disorder characterized by hypotonia, movement disorders, dysautonomic features, and behavioral disturbances.1, 2, 3, 4, 5