FA2H

Reviewed October 2012

What is the official name of the FA2H gene?

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.

What is the normal function of the FA2H gene?

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.

How are changes in the FA2H gene related to health conditions?

fatty acid hydroxylase-associated neurodegeneration - caused by mutations in the FA2H gene

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.

Where is the FA2H gene located?

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.

Where can I find additional information about FA2H?

You and your healthcare professional may find the following resources about FA2H helpful.

Educational resources - Information pages
Basic Neurochemistry: Molecular, Cellular and Medical Aspects (sixth edition, 1999): Characteristic Composition of Myelin (http://www.ncbi.nlm.nih.gov/books/NBK28221/)
Gene Reviews - Clinical summary (http://www.ncbi.nlm.nih.gov/books/NBK56080/)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for FA2H (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=79152%5Bgeneid%5D)

You may also be interested in these resources, which are designed for genetics professionals and researchers.

PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/pubmed?term=((FA2H%5BTIAB%5D)%20OR%20(fatty%20acid%202-hydroxylase%5BTIAB%5D))%20OR%20((FAH1%5BTIAB%5D)%20OR%20(SCS7%5BTIAB%5D)%20OR%20(SPG35%5BTIAB%5D)%20OR%20(fatty%20acid%20alpha-hydroxylase%5BTIAB%5D))%20AND%20((Genes%5BMH%5D)%20OR%20(Genetic%20Phenomena%5BMH%5D))%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%20720%20days%22%5Bdp%5D)
OMIM - Genetic disorder catalog (http://omim.org/entry/611026)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_FA2H.html)
- Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/79152)
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=79152)
- HUGO Gene Nomenclature Committee (http://www.genenames.org/data/hgnc_data.php?hgnc_id=21197)

What other names do people use for the FA2H gene or gene products?

FA2H_HUMAN
FAAH
FAH1
fatty acid alpha-hydroxylase
fatty acid hydroxylase domain containing 1
FAXDC1
FLJ25287
SCS7
spastic paraplegia 35 (autosomal recessive)
SPG35

See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.

What glossary definitions help with understanding FA2H?

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).

References

Alderson NL, Rembiesa BM, Walla MD, Bielawska A, Bielawski J, Hama H. The human FA2H gene encodes a fatty acid 2-hydroxylase. J Biol Chem. 2004 Nov 19;279(47):48562-8. Epub 2004 Aug 27. (http://www.ncbi.nlm.nih.gov/pubmed/15337768?dopt=Abstract)
Dick KJ, Eckhardt M, Paisán-Ruiz C, Alshehhi AA, Proukakis C, Sibtain NA, Maier H, Sharifi R, Patton MA, Bashir W, Koul R, Raeburn S, Gieselmann V, Houlden H, Crosby AH. Mutation of FA2H underlies a complicated form of hereditary spastic paraplegia (SPG35). Hum Mutat. 2010 Apr;31(4):E1251-60. doi: 10.1002/humu.21205. (http://www.ncbi.nlm.nih.gov/pubmed/20104589?dopt=Abstract)
Edvardson S, Hama H, Shaag A, Gomori JM, Berger I, Soffer D, Korman SH, Taustein I, Saada A, Elpeleg O. Mutations in the fatty acid 2-hydroxylase gene are associated with leukodystrophy with spastic paraparesis and dystonia. Am J Hum Genet. 2008 Nov;83(5):643-8. doi: 10.1016/j.ajhg.2008.10.010. (http://www.ncbi.nlm.nih.gov/pubmed/19068277?dopt=Abstract)
Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/79152)
Gene Review: Fatty Acid Hydroxylase-Associated Neurodegeneration (http://www.ncbi.nlm.nih.gov/books/NBK56080/)
Gregory A, Hayflick SJ. Genetics of neurodegeneration with brain iron accumulation. Curr Neurol Neurosci Rep. 2011 Jun;11(3):254-61. doi: 10.1007/s11910-011-0181-3. Review. (http://www.ncbi.nlm.nih.gov/pubmed/21286947?dopt=Abstract)
Kruer MC, Paisán-Ruiz C, Boddaert N, Yoon MY, Hama H, Gregory A, Malandrini A, Woltjer RL, Munnich A, Gobin S, Polster BJ, Palmeri S, Edvardson S, Hardy J, Houlden H, Hayflick SJ. Defective FA2H leads to a novel form of neurodegeneration with brain iron accumulation (NBIA). Ann Neurol. 2010 Nov;68(5):611-8. doi: 10.1002/ana.22122. (http://www.ncbi.nlm.nih.gov/pubmed/20853438?dopt=Abstract)
OMIM: FATTY ACID 2-HYDROXYLASE (http://omim.org/entry/611026)
Schneider SA, Bhatia KP. Three faces of the same gene: FA2H links neurodegeneration with brain iron accumulation, leukodystrophies, and hereditary spastic paraplegias. Ann Neurol. 2010 Nov;68(5):575-7. doi: 10.1002/ana.22211. Erratum in: Ann Neurol. 2011 Jul;70(1):187. (http://www.ncbi.nlm.nih.gov/pubmed/21031573?dopt=Abstract)

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.



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