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Reviewed April 2011

What is the official name of the CAPN3 gene?

The official name of this gene is “calpain 3.”

CAPN3 is the gene's official symbol. The CAPN3 gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the CAPN3 gene?

The CAPN3 gene provides instructions for making an enzyme called calpain-3, which is found within muscle cells in structures called sarcomeres. Sarcomeres are the basic unit of muscle contraction. They are made of proteins that generate the mechanical force needed for muscles to contract.

The function of the calpain-3 enzyme is not well understood. Researchers suggest it may help cut (cleave) damaged proteins into shorter segments to facilitate their removal from the sarcomere. Studies have also shown that calpain-3 attaches (binds) to proteins involved in controlling the ability of muscle fibers to stretch (elasticity) and in cell signaling. However, its specific roles in these processes are unknown.

How are changes in the CAPN3 gene related to health conditions?

limb-girdle muscular dystrophy - caused by mutations in the CAPN3 gene

More than 300 mutations in the CAPN3 gene have been identified in people with limb-girdle muscular dystrophy type 2A. This form of limb-girdle muscular dystrophy is also called calpainopathy.

Limb-girdle muscular dystrophy is a group of related disorders characterized by muscle weakness and wasting, particularly in the shoulders, hips, and limbs. CAPN3 gene mutations are the most common cause of limb-girdle muscular dystrophy. These mutations account for approximately 30 percent of limb-girdle muscular dystrophy cases overall, although the percentage varies by specific population.

Most CAPN3 gene mutations change one protein building block (amino acid) in the calpain-3 enzyme. These mutations result in a calpain-3 enzyme that is abnormally short or unstable. Disruption of the enzyme's ability to properly cleave proteins for removal from the sarcomere may allow these waste proteins to accumulate in muscle tissue and become toxic. Other mechanisms have also been suggested to account for the muscle damage that underlies limb-girdle muscular dystrophy in people with CAPN3 gene mutations.

Where is the CAPN3 gene located?

Cytogenetic Location: 15q15.1

Molecular Location on chromosome 15: base pairs 42,359,500 to 42,412,317

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The CAPN3 gene is located on the long (q) arm of chromosome 15 at position 15.1.

The CAPN3 gene is located on the long (q) arm of chromosome 15 at position 15.1.

More precisely, the CAPN3 gene is located from base pair 42,359,500 to base pair 42,412,317 on chromosome 15.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about CAPN3?

You and your healthcare professional may find the following resources about CAPN3 helpful.

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

What other names do people use for the CAPN3 gene or gene products?

  • calcium-activated neutral proteinase 3
  • calpain-3
  • calpain-3 isoform c
  • calpain 3, (p94)
  • calpain L3
  • calpain, large polypeptide L3
  • calpain p94, large [catalytic] subunit
  • CANP3
  • CANPL3
  • LGMD2A
  • muscle-specific calcium-activated neutral protease 3 large subunit
  • nCL-1
  • new calpain 1
  • p94

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding CAPN3?

amino acid ; calcium ; catalytic ; cell ; contraction ; enzyme ; gene ; muscle cells ; muscular dystrophy ; population ; protease ; protein ; proteinase ; sarcomere ; subunit ; tissue ; toxic ; wasting

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (10 links)


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? in the Handbook.

Reviewed: April 2011
Published: February 8, 2016