|http://ghr.nlm.nih.gov/ A service of the U.S. National Library of Medicine®|
The official name of this gene is “dopa decarboxylase (aromatic L-amino acid decarboxylase).”
DDC is the gene's official symbol. The DDC gene is also known by other names, listed below.
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.
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.
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.
Cytogenetic Location: 7p12.2
Molecular Location on chromosome 7: base pairs 50,526,133 to 50,633,153
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 50,526,133 to base pair 50,633,153 on chromosome 7.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
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.
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
amino acid ; atom ; attention deficit hyperactivity disorder ; bipolar disorder ; carboxyl ; carboxyl group ; deficiency ; developmental delay ; dopamine ; enzyme ; gene ; hyperactivity ; nervous system ; neurotransmitters ; nicotine ; oxygen ; protein ; schizophrenia ; tyrosine
You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://www.ghr.nlm.nih.gov/glossary).
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? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.