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The official name of this gene is “dopamine beta-hydroxylase (dopamine beta-monooxygenase).”
DBH is the gene's official symbol. The DBH gene is also known by other names, listed below.
The DBH gene provides instructions for producing the enzyme dopamine beta (β)-hydroxylase. This enzyme converts dopamine to norepinephrine, both of which are chemical messengers (neurotransmitters) that transmit signals between nerve cells. Norepinephrine plays an important role in the autonomic nervous system, which controls involuntary body processes such as the regulation of blood pressure and body temperature.
At least six mutations in the DBH gene have been found to cause dopamine β-hydroxylase deficiency. The most common mutation (usually written as IVS1+2T>C) interferes with the normal processing of dopamine β-hydroxylase. As a result of this mutation, an abnormally short, nonfunctional version of the enzyme is produced. A lack of functional dopamine β-hydroxylase leads to a shortage of norepinephrine, which causes difficulty with regulating blood pressure and other autonomic nervous system problems seen in dopamine β-hydroxylase deficiency.
Studies have shown certain variations (polymorphisms) in the DBH gene to be associated with increased risk of attention deficit hyperactivity disorder (ADHD). DBH gene polymorphisms are also thought to increase the risk of psychotic symptoms in people with schizophrenia or unipolar major depression. Other studies, however, have not supported these findings. Many genetic and environmental factors are believed to contribute to these complex conditions.
Cytogenetic Location: 9q34
Molecular Location on chromosome 9: base pairs 136,501,484 to 136,524,465
The DBH gene is located on the long (q) arm of chromosome 9 at position 34.
More precisely, the DBH gene is located from base pair 136,501,484 to base pair 136,524,465 on chromosome 9.
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 DBH 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.
ADHD ; attention deficit hyperactivity disorder ; autonomic nervous system ; deficiency ; depression ; dopamine ; enzyme ; gene ; hyperactivity ; involuntary ; mutation ; nervous system ; neurotransmitters ; psychotic ; schizophrenia
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.