Reviewed June 2008
What is the official name of the ALDH5A1 gene?
The official name of this gene is “aldehyde dehydrogenase 5 family, member A1.”
ALDH5A1 is the gene's official symbol. The ALDH5A1 gene is also known by other names, listed below.
What is the normal function of the ALDH5A1 gene?
The ALDH5A1 gene provides instructions for producing the succinic semialdehyde dehydrogenase enzyme. This enzyme is found in the energy-producing centers of cells (mitochondria). Succinic semialdehyde dehydrogenase is involved in the breakdown of a chemical that transmits signals in the brain (neurotransmitter) called gamma-amino butyric acid (GABA). The primary role of GABA is to prevent the brain from being overloaded with too many signals. Once GABA molecules have been released from nerve cells, they are broken down by succinic semialdehyde dehydrogenase and other enzymes.
Does the ALDH5A1 gene share characteristics with other genes?
The ALDH5A1 gene belongs to a family of genes called ALDH (aldehyde dehydrogenases).
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? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.
How are changes in the ALDH5A1 gene related to health conditions?
- succinic semialdehyde dehydrogenase deficiency - caused by mutations in the ALDH5A1 gene
At least 35 mutations in the ALDH5A1 gene have been found to cause succinic semialdehyde dehydrogenase deficiency. Most of these mutations change one protein building block (amino acid) in the succinic semialdehyde dehydrogenase enzyme. Mutations in the ALDH5A1 gene lead to the production of an enzyme with little or no activity. A lack of functional succinic semialdehyde dehydrogenase disrupts the conversion of succinic semialdehyde to succinic acid. Instead, succinic semialdehyde is converted back into GABA or to a related molecule, gamma-hydroxybutyrate (GHB). It is unclear how increases in GHB and GABA cause developmental delay, seizures, and other features of succinic semialdehyde dehydrogenase deficiency.
Where is the ALDH5A1 gene located?
Cytogenetic Location: 6p22
Molecular Location on chromosome 6: base pairs 24,494,968 to 24,537,206
The ALDH5A1 gene is located on the short (p) arm of chromosome 6 at position 22.
More precisely, the ALDH5A1 gene is located from base pair 24,494,968 to base pair 24,537,206 on chromosome 6.
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 ALDH5A1?
You and your healthcare professional may find the following resources about ALDH5A1 helpful.
Educational resources - Information pages
- Basic Neurochemistry (sixth edition, 1999): GABA shunt reactions are responsible for the synthesis, conservation and metabolism of GABA (http://www.ncbi.nlm.nih.gov/books/NBK27979/?rendertype=figure&id=A1180)
- Basic Neurochemistry (sixth edition, 1999): GABA Synthesis, Uptake and Release (http://www.ncbi.nlm.nih.gov/books/NBK27979/)
- Gene Reviews - Clinical summary (http://www.ncbi.nlm.nih.gov/books/NBK1195)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for ALDH5A1 (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=7915%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=%28ALDH5A1%5BTIAB%5D%29%20OR%20%28%28SSDH%5BTIAB%5D%29%20OR%20%28SSADH%5BTIAB%5D%29%29%20AND%20%28%28Genes%5BMH%5D%29%20OR%20%28Genetic%20Phenomena%5BMH%5D%29%29%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%202880%20days%22%5Bdp%5D)
- OMIM - Genetic disorder catalog (http://omim.org/entry/610045)
Research Resources - Tools for researchers
- HGNC Gene Family: Aldehyde dehydrogenases (http://www.genenames.org/genefamilies/ALDH)
- HGNC Gene Symbol Report (http://www.genenames.org/cgi-bin/gene_symbol_report?q=data/hgnc_data.php&hgnc_id=408)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/7915)
What other names do people use for the ALDH5A1 gene or gene products?
- aldehyde dehydrogenase 5A1
- aldehyde dehydrogenase 5 family, member A1 (succinate-semialdehyde dehydrogenase)
- mitochondrial succinate semialdehyde dehydrogenase
- NAD(+)-dependent succinic semialdehyde dehydrogenase
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 ALDH5A1?
amino acid ;
developmental delay ;
You may find definitions for these and many other terms in the Genetics Home Reference
- Akaboshi S, Hogema BM, Novelletto A, Malaspina P, Salomons GS, Maropoulos GD, Jakobs C, Grompe M, Gibson KM. Mutational spectrum of the succinate semialdehyde dehydrogenase (ALDH5A1) gene and functional analysis of 27 novel disease-causing mutations in patients with SSADH deficiency. Hum Mutat. 2003 Dec;22(6):442-50. (http://www.ncbi.nlm.nih.gov/pubmed/14635103?dopt=Abstract)
- OMIM: ALDEHYDE DEHYDROGENASE 5 FAMILY, MEMBER A1 (http://omim.org/entry/610045)
- Blasi P, Boyl PP, Ledda M, Novelletto A, Gibson KM, Jakobs C, Hogema B, Akaboshi S, Loreni F, Malaspina P. Structure of human succinic semialdehyde dehydrogenase gene: identification of promoter region and alternatively processed isoforms. Mol Genet Metab. 2002 Aug;76(4):348-62. (http://www.ncbi.nlm.nih.gov/pubmed/12208142?dopt=Abstract)
- Gordon N. Succinic semialdehyde dehydrogenase deficiency (SSADH) (4-hydroxybutyric aciduria, gamma-hydroxybutyric aciduria). Eur J Paediatr Neurol. 2004;8(5):261-5. Review. (http://www.ncbi.nlm.nih.gov/pubmed/15341910?dopt=Abstract)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/7915)
- Pearl PL, Gibson KM, Acosta MT, Vezina LG, Theodore WH, Rogawski MA, Novotny EJ, Gropman A, Conry JA, Berry GT, Tuchman M. Clinical spectrum of succinic semialdehyde dehydrogenase deficiency. Neurology. 2003 May 13;60(9):1413-7. (http://www.ncbi.nlm.nih.gov/pubmed/12743223?dopt=Abstract)
- Pearl PL, Novotny EJ, Acosta MT, Jakobs C, Gibson KM. Succinic semialdehyde dehydrogenase deficiency in children and adults. Ann Neurol. 2003;54 Suppl 6:S73-80. Review. (http://www.ncbi.nlm.nih.gov/pubmed/12891657?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
See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.