The animated videos in NORD’s Rare Disease Video Library provide brief introductions to rare disease topics for patients, caregivers, students, professionals and the public. NORD collaborates with medical experts, patient organizations, videographers and Osmosis to develop the videos, which are made possible by individual donations, educational grants and corporate sponsorships. NORD is solely responsible for the content.
Aromatic l-amino acid decarboxylase (AADC) deficiency is a very rare genetic disorder characterized by decreased activity of aromatic l-amino acid decarboxylase, an enzyme involved in the building (synthesis) of neurotransmitters (dopamine and serotonin), which are responsible for the communication between neurons in the nervous system. Although affected individuals can appear normal at birth, most will develop symptoms during the first months of life. AADC deficiency most commonly leads to decreased muscle tone (hypotonia), movement disorders including abnormal eyes movement (oculogyric crises), developmental delay, restricted growth (failure to thrive), and disruption of the part of the nervous system responsible for unconscious modulation of body functions such as heartbeat (autonomic nervous system). Medication is available to manage the symptoms, but response to treatment greatly varies among affected individuals, and an optimal treatment regimen can be difficult to achieve. There is currently no cure for the disease, but gene therapy has shown potential to improve symptoms in clinical trials.