SACS

Reviewed April 2008

What is the official name of the SACS gene?

The official name of this gene is “spastic ataxia of Charlevoix-Saguenay (sacsin).”

SACS is the gene's official symbol. The SACS gene is also known by other names, listed below.

What is the normal function of the SACS gene?

The SACS gene provides instructions for producing a protein called sacsin. Sacsin is found in the brain, skin cells, muscles used for movement (skeletal muscles), and at low levels in the pancreas, but the specific function of the protein is unknown. Research suggests that sacsin may play a role in folding newly produced proteins into the proper 3-dimensional shape because it shares similar regions with other proteins that perform this function.

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

autosomal recessive spastic ataxia of Charlevoix-Saguenay - caused by mutations in the SACS gene: Approximately 28 mutations in the SACS gene have been found to cause autosomal recessive spastic ataxia of Charlevoix-Saguenay, commonly called ARSACS. Two mutations have been found frequently in affected people from Quebec. One of these mutations deletes a DNA building block (nucleotide) called thymine at position 6594 in the SACS gene (written as 6594delT). This mutation is found in more than 90 percent of people with ARSACS in Quebec. The other mutation replaces the nucleotide cytosine with the nucleotide thymine at position 5254 in the SACS gene (written as C5254T). Both of these mutations lead to production of a sacsin protein that is abnormally short and nonfunctional. Mutations causing ARSACS in people outside of Quebec are varied and usually unique to that person or family. Most of these mutations either delete one or more nucleotides or replace one nucleotide with another nucleotide in the SACS gene. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles and results in the signs and symptoms of ARSACS.

Where is the SACS gene located?

Cytogenetic Location: 13q12

Molecular Location on chromosome 13: base pairs 23,902,964 to 24,007,840

The SACS gene is located on the long (q) arm of chromosome 13 at position 12.

More precisely, the SACS gene is located from base pair 23,902,964 to base pair 24,007,840 on chromosome 13.

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 SACS?

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

Educational resources - Information pages
Clincal Methods (third edition, 1990): The Motor System and Gait (http://www.ncbi.nlm.nih.gov/books/NBK391/)
Gene Reviews - Clinical summary (http://www.ncbi.nlm.nih.gov/books/NBK1255/)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for SACS (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=26278%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=((SACS%5BTIAB%5D)%20AND%20(spastic%20ataxia%5BALL%5D)%20OR%20(sacsin%5BTIAB%5D))%20AND%20((Genes%5BMH%5D)%20OR%20(Genetic%20Phenomena%5BMH%5D))%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%201800%20days%22%5Bdp%5D)
OMIM - Genetic disorder catalog (http://omim.org/entry/604490)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_SACS.html)
- Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/26278)
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=26278)
- HUGO Gene Nomenclature Committee (http://www.genenames.org/data/hgnc_data.php?hgnc_id=10519)

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

ARSACS
DNAJC29
KIAA0730
SACS_HUMAN
sacsin

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 SACS?

ataxia ; autosomal ; autosomal recessive ; chaperone ; cytosine ; DNA ; domain ; gene ; mutation ; nucleotide ; pancreas ; protein ; recessive ; thymine

You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://www.ghr.nlm.nih.gov/glossary).

References

Engert JC, Bérubé P, Mercier J, Doré C, Lepage P, Ge B, Bouchard JP, Mathieu J, Melançon SB, Schalling M, Lander ES, Morgan K, Hudson TJ, Richter A. ARSACS, a spastic ataxia common in northeastern Québec, is caused by mutations in a new gene encoding an 11.5-kb ORF. Nat Genet. 2000 Feb;24(2):120-5. (http://www.ncbi.nlm.nih.gov/pubmed/10655055?dopt=Abstract)
Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/26278)
Mercier J, Prévost C, Engert JC, Bouchard JP, Mathieu J, Richter A. Rapid detection of the sacsin mutations causing autosomal recessive spastic ataxia of Charlevoix-Saguenay. Genet Test. 2001 Fall;5(3):255-9. (http://www.ncbi.nlm.nih.gov/pubmed/11788093?dopt=Abstract)
OMIM: SACSIN (http://omim.org/entry/604490)
Takiyama Y. Autosomal recessive spastic ataxia of Charlevoix-Saguenay. Neuropathology. 2006 Aug;26(4):368-75. (http://www.ncbi.nlm.nih.gov/pubmed/16961075?dopt=Abstract)
Takiyama Y. Sacsinopathies: sacsin-related ataxia. Cerebellum. 2007;6(4):353-9. doi: 10.1080/14734220701230466. Epub 2007 Feb 28. (http://www.ncbi.nlm.nih.gov/pubmed/17853117?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.