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Reviewed May 2008

What is the official name of the DDC gene?

The official name of this gene is “dopa decarboxylase.”

DDC is the gene's official symbol. The DDC gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the DDC gene?

The DDC gene provides instructions for making the aromatic l-amino acid decarboxylase (AADC) enzyme, which is important in the brain and nervous system. This enzyme takes part in the pathway that produces dopamine and serotonin, which are chemical messengers that transmit signals between nerve cells (neurotransmitters).

Dopamine is produced from the protein building block (amino acid) tyrosine, and serotonin is produced from the amino acid tryptophan. Both neurotransmitters are produced in two-step processes. First, other enzymes control the reactions that convert tyrosine to L-dopa, and tryptophan to 5-hydroxytryptophan. The AADC enzyme then converts L-dopa and 5-hydroxytryptophan to dopamine and serotonin, respectively. To do this, it removes a molecular structure called a carboxyl group, consisting of a carbon atom, two oxygen atoms, and a hydrogen atom.

How are changes in the DDC gene related to health conditions?

aromatic l-amino acid decarboxylase deficiency - caused by mutations in the DDC gene

Mutations in the DDC gene result in reduced activity of the AADC enzyme. Without enough of this enzyme, nerve cells produce less dopamine and serotonin. Dopamine and serotonin are necessary for normal nervous system function, and changes in the levels of these neurotransmitters contribute to the developmental delay, intellectual disability, abnormal movements, and autonomic dysfunction seen in people with AADC deficiency.

other disorders - associated with the DDC gene

Studies have shown certain variations (polymorphisms) in the DDC gene to be associated with increased risk of nicotine dependence, schizophrenia, bipolar disorder, and attention deficit hyperactivity disorder; however, other studies have not supported these findings. Many genetic and environmental factors are believed to contribute to these complex conditions.

Where is the DDC gene located?

Cytogenetic Location: 7p12.2

Molecular Location on chromosome 7: base pairs 50,458,436 to 50,565,457

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The DDC gene is located on the short (p) arm of chromosome 7 at position 12.2.

The DDC gene is located on the short (p) arm of chromosome 7 at position 12.2.

More precisely, the DDC gene is located from base pair 50,458,436 to base pair 50,565,457 on chromosome 7.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about DDC?

You and your healthcare professional may find the following resources about DDC helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the DDC gene or gene products?

  • AADC
  • aromatic L-amino acid decarboxylase
  • dopa decarboxylase (aromatic L-amino acid decarboxylase)

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding DDC?

References (9 links)


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Reviewed: May 2008
Published: February 8, 2016