About AADC Deficiency


AADC deficiency is caused by mutations in the DDC gene, which carries the instructions necessary to make the aromatic l-amino acid decarboxylase or the AADC enzyme. This enzyme is vital for the production of dopamine and serotonin, two very important neurotransmitters.

Mutations in the DDC gene lead to low and insufficient levels of the AADC enzyme being produced, affecting the production of dopamine and serotonin, and impeding communication between the brain and other organs.

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The symptoms of AADC deficiency and their severity vary from person to person. They include those caused by developmental delays, and those that result from the impact of the AADC enzyme’s loss on the autonomic nervous system, which controls involuntary bodily processes such as blood pressure and temperature regulation.

Symptoms of AADC can lead to a lack of energy, difficulties with eating, and sleep problems.

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Diagnostic tests to confirm AADC deficiency include measuring dopamine, norepinephrine, epinephrine, and serotonin levels in the cerebrospinal fluid, testing for AADC enzyme activity in the blood, and screening the DDC gene for mutations. Two test results indicating AADC deficiency are usually necessary to confirm a diagnosis.

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