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Reviewed April 2014
What is the official name of the MT-CYB gene?
The official name of this gene is “mitochondrially encoded cytochrome b.”
MT-CYB is the gene's official symbol. The MT-CYB 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 MT-CYB gene?
The MT-CYB gene provides instructions for making a protein called cytochrome b. This protein plays a key role in structures called mitochondria, which convert the energy from food into a form that cells can use. Cytochrome b is one of 11 components of a group of proteins called complex III. In mitochondria, complex III performs one step of a process known as oxidative phosphorylation, in which oxygen and simple sugars are used to create adenosine triphosphate (ATP), the cell's main energy source. During oxidative phosphorylation, the protein complexes, including complex III, drive the production of ATP through a step-by-step transfer of negatively charged particles called electrons. Cytochrome b is involved in the transfer of these particles through complex III.
Although most DNA is packaged in chromosomes within the nucleus (nuclear DNA), mitochondria also have a small amount of their own DNA, called mitochondrial DNA (mtDNA). This type of DNA contains many genes essential for normal mitochondrial function. Cytochrome b is the only component of complex III that is produced from a gene found in mitochondrial DNA.
Does the MT-CYB gene share characteristics with other genes?
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? in the Handbook.
How are changes in the MT-CYB gene related to health conditions?
Where is the MT-CYB gene located?
The MT-CYB gene is located in mitochondrial DNA.
Molecular Location in mitochondrial DNA: base pairs 14,747 to 15,887
(Homo sapiens Annotation Release 107, GRCh38.p2) (
Where can I find additional information about MT-CYB?
You and your healthcare professional may find the following resources about MT-CYB 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 MT-CYB 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 MT-CYB?
acids ; adenosine triphosphate ; ATP ; cell ; charged particles ; coenzyme Q ; deficiency ; DNA ; electron ; gene ; heteroplasmy ; mitochondria ; mutation ; nucleus ; oxidative phosphorylation ; oxidoreductase ; oxygen ; phosphorylation ; protein ; tissue
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (5 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.