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Reviewed June 2015

What is the official name of the TPM2 gene?

The official name of this gene is “tropomyosin 2 (beta).”

TPM2 is the gene's official symbol. The TPM2 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 TPM2 gene?

The TPM2 gene provides instructions for making a protein called beta (β)-tropomyosin, which is part of the tropomyosin protein family. Tropomyosin proteins regulate the tensing of muscle fibers (muscle contraction) by controlling the binding of two muscle proteins, myosin and actin. In non-muscle cells, tropomyosin proteins play a role in controlling cell shape.

β-tropomyosin is found primarily in skeletal muscles, which are the muscles used for movement. This protein helps regulate muscle contraction by interacting with other muscle proteins, particularly myosin and actin. These interactions are essential for stabilizing and maintaining structures called sarcomeres within muscle cells. Sarcomeres are the basic units of muscle contraction; they are made of proteins that generate the mechanical force needed for muscles to contract.

How are changes in the TPM2 gene related to health conditions?

cap myopathy - caused by mutations in the TPM2 gene

At least three TPM2 gene mutations have been identified in people with cap myopathy, a disorder that leads to muscle weakness (myopathy) and poor muscle tone (hypotonia). These mutations delete or duplicate genetic material in the TPM2 gene or replace single protein building blocks (amino acids) in the β-tropomyosin protein sequence. The specific effects of these TPM2 gene mutations are unclear, but researchers suggest they may interfere with normal actin-myosin binding, impairing muscle contraction and resulting in the muscle weakness that occurs in cap myopathy.

distal arthrogryposis type 1 - caused by mutations in the TPM2 gene

At least three mutations in the TPM2 gene have been found to cause distal arthrogryposis type 1, a disorder characterized by joint deformities (contractures) in the hands and feet. It is unclear how these mutations lead to contractures in people with distal arthrogryposis type 1, or why the joint problems are typically limited to the hands and feet. However, researchers speculate that contractures may be related to problems with muscle contraction that limit the movement of joints before birth.

Sheldon-Hall syndrome - associated with the TPM2 gene

At least six TPM2 gene mutations have been identified in people with Sheldon-Hall syndrome, a muscle and skeletal disorder similar to distal arthrogryposis type 1 (described above) that impairs joint movement in the hands and feet. Mutations in the TPM2 gene may alter the structure of β-tropomyosin and disrupt the protein's normal function in controlling muscle contractions, resulting in the contractures and other muscle and skeletal abnormalities associated with this condition.

Genetics Home Reference provides information about nemaline myopathy, which is also associated with changes in the TPM2 gene.

Where is the TPM2 gene located?

Cytogenetic Location: 9p13

Molecular Location on chromosome 9: base pairs 35,681,993 to 35,690,056

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

The TPM2 gene is located on the short (p) arm of chromosome 9 at position 13.

The TPM2 gene is located on the short (p) arm of chromosome 9 at position 13.

More precisely, the TPM2 gene is located from base pair 35,681,993 to base pair 35,690,056 on chromosome 9.

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

Where can I find additional information about TPM2?

You and your healthcare professional may find the following resources about TPM2 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 TPM2 gene or gene products?

  • beta-tropomyosin
  • NEM4
  • TMSB
  • tropomyosin-2
  • tropomyosin beta chain
  • tropomyosin, skeletal muscle beta

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 TPM2?

acids ; actin ; arthrogryposis ; cell ; contraction ; distal ; gene ; hypotonia ; joint ; muscle cells ; muscle tone ; myosin ; protein ; protein sequence ; skeletal muscle ; syndrome

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

See also Understanding Medical Terminology.

References (13 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: June 2015
Published: February 8, 2016