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The official name of this gene is “selenoprotein N, 1.”
SEPN1 is the gene's official symbol. The SEPN1 gene is also known by other names, listed below.
The SEPN1 gene provides instructions for making a protein called selenoprotein N, 1. This protein is part of a family of selenoproteins, which have several critical functions within the body. Selenoproteins are primarily involved in chemical reactions called oxidation-reduction reactions, which are essential for protecting cells from damage caused by unstable oxygen-containing molecules. Selenoprotein N, 1 is likely involved in protecting cells against oxidative stress. Oxidative stress occurs when unstable molecules called free radicals accumulate to levels that damage or kill cells.
The exact function of selenoprotein N, 1 is unknown. This protein is highly active in many tissues before birth and may be involved in the formation of muscle tissue (myogenesis). Selenoprotein N, 1 may also be important for normal muscle function after birth, although it is active at much lower levels in adult tissues. This protein contains a region that likely allows it to bind to calcium. This region is of interest because calcium plays an important role in triggering muscle contractions, which allow the body to move.
The SEPN1 gene belongs to a family of genes called EF-hand domain containing (EF-hand domain containing).
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.
At least one mutation in the SEPN1 gene has been found to cause congenital fiber-type disproportion. This mutation replaces the protein building block (amino acid) glycine with the amino acid serine at position 315 in selenoprotein N, 1 (written as Gly315Ser or G315S). It is unclear how this mutation causes muscle weakness and the other features of congenital fiber-type disproportion.
At least 17 mutations in the SEPN1 gene have been identified in people with the classic form of multiminicore disease. Many of these genetic changes lead to the production of an abnormally short version of selenoprotein N, 1. Other mutations change single protein building blocks (amino acids) in critical regions of the protein. The effects of changes in the structure and function of selenoprotein N, 1 are unknown, and researchers are working to determine how these changes lead to muscle weakness and the other characteristic features of multiminicore disease.
Mutations in the SEPN1 gene are responsible for several other rare muscle disorders, including rigid spine muscular dystrophy and desmin-related myopathy with Mallory body-like inclusions. These conditions cause muscle weakness, particularly in the muscles of the trunk and neck. Affected individuals also have decreased muscle tone (hypotonia), abnormal curvature of the spine (scoliosis), and serious breathing problems. Because they have a similar pattern of signs and symptoms and are caused by mutations in the same gene, many researchers believe that these conditions are all part of a single syndrome with variable signs and symptoms. Together, muscle diseases caused by SEPN1 gene mutations are known as SEPN1-related myopathy.
Cytogenetic Location: 1p36.13
Molecular Location on chromosome 1: base pairs 25,800,175 to 25,818,221
The SEPN1 gene is located on the short (p) arm of chromosome 1 at position 36.13.
More precisely, the SEPN1 gene is located from base pair 25,800,175 to base pair 25,818,221 on chromosome 1.
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 SEPN1 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 ; amino acid ; calcium ; congenital ; decreased muscle tone ; free radicals ; gene ; glycine ; hypotonia ; Mb ; muscle tone ; muscular dystrophy ; mutation ; oxidation ; oxidative stress ; oxygen ; protein ; scoliosis ; serine ; stress ; syndrome ; tissue
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.