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The official name of this gene is “fatty acid 2-hydroxylase.”
FA2H is the gene's official symbol. The FA2H gene is also known by other names, listed below.
The FA2H gene provides instructions for making an enzyme called fatty acid 2-hydroxylase. This enzyme modifies fatty acids, which are building blocks used to make fats (lipids). Specifically, fatty acid 2-hydroxylase adds a single oxygen atom to a hydrogen atom at a particular point on a fatty acid to create a 2-hydroxylated fatty acid. Certain 2-hydroxylated fatty acids are important in forming normal myelin; myelin is the protective covering that insulates nerves and ensures the rapid transmission of nerve impulses. The part of the brain and spinal cord that contains myelin is called white matter.
At least nine mutations in the FA2H gene have been identified in people with fatty acid hydroxylase-associated neurodegeneration (FAHN). FAHN is a progressive disorder of the nervous system characterized by problems with movement and vision that begin during childhood or adolescence and worsen with age. Brain scans of affected individuals show abnormal accumulation of iron in the brain, especially in a region that is involved in movement.
The FA2H gene mutations that cause FAHN reduce or eliminate the function of the fatty acid 2-hydroxylase enzyme. Reduction of this enzyme's function may result in abnormal myelin that is prone to deterioration (demyelination), leading to a loss of white matter (leukodystrophy). Leukodystrophy is likely involved in the development of the movement problems and other neurological abnormalities that occur in FAHN. Iron accumulation in the brain is probably also involved, although it is unclear how FA2H gene mutations lead to the buildup of iron.
People with FA2H gene mutations and some of the movement problems seen in FAHN were once classified as having a separate disorder called spastic paraplegia 35. People with mutations in this gene resulting in intellectual decline and optic nerve atrophy were said to have a disorder called FA2H-related leukodystrophy. However, these conditions are now generally considered to be forms of FAHN.
Cytogenetic Location: 16q23
Molecular Location on chromosome 16: base pairs 74,746,852 to 74,808,728
The FA2H gene is located on the long (q) arm of chromosome 16 at position 23.
More precisely, the FA2H gene is located from base pair 74,746,852 to base pair 74,808,728 on chromosome 16.
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 FA2H 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.
acids ; atom ; atrophy ; autosomal ; autosomal recessive ; demyelination ; domain ; enzyme ; fatty acids ; gene ; iron ; leukodystrophy ; nervous system ; neurological ; optic nerve ; oxygen ; paraplegia ; recessive ; white matter
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.