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Reviewed July 2009
What is the official name of the HADHB gene?
The official name of this gene is “hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), beta subunit.”
HADHB is the gene's official symbol. The HADHB 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 HADHB gene?
The HADHB gene provides instructions for making part of an enzyme complex called mitochondrial trifunctional protein. This enzyme complex functions in mitochondria, the energy-producing centers within cells. Mitochondrial trifunctional protein is made of eight parts (subunits). Four alpha subunits are produced from the HADHA gene, and four beta subunits are produced from the HADHB gene. As the name suggests, mitochondrial trifunctional protein contains three enzymes that each perform a different function. The beta subunits contain one of the enzymes, known as long-chain 3-keto-acyl-CoA thiolase. The alpha subunits contain the other two enzymes. These enzymes are essential for fatty acid oxidation, which is the multistep process that breaks down (metabolizes) fats and converts them to energy.
Mitochondrial trifunctional protein is required to metabolize a group of fats called long-chain fatty acids. Long-chain fatty acids are found in foods such as milk and certain oils. These fatty acids are stored in the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues.
How are changes in the HADHB gene related to health conditions?
Where is the HADHB gene located?
Cytogenetic Location: 2p23
Molecular Location on chromosome 2: base pairs 26,244,748 to 26,290,465
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The HADHB gene is located on the short (p) arm of chromosome 2 at position 23.
More precisely, the HADHB gene is located from base pair 26,244,748 to base pair 26,290,465 on chromosome 2.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about HADHB?
You and your healthcare professional may find the following resources about HADHB 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 HADHB gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
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 HADHB?
acids ; acute ; blood clotting ; breakdown ; cell ; clotting ; CoA ; coenzyme A ; coma ; deficiency ; dehydrogenase ; enzyme ; fasting ; fatty acids ; fatty liver ; fetus ; gene ; hemolysis ; hypoglycemia ; hypotonia ; lethargy ; liver failure ; maternal ; mitochondria ; muscle tone ; mutation ; oxidation ; placenta ; platelets ; protein ; subunit ; syndrome ; toxic
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (14 links)