Skip Navigation
Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®


Reviewed January 2014

What is the official name of the TRPM1 gene?

The official name of this gene is “transient receptor potential cation channel subfamily M member 1.”

TRPM1 is the gene's official symbol. The TRPM1 gene is also known by other names, listed below.

What is the normal function of the TRPM1 gene?

The TRPM1 gene provides instructions for making a protein called transient receptor potential cation channel subfamily M member 1 (TRPM1). This protein acts as a channel, transporting positively charged atoms (cations) into cells. The TRPM1 channel is found on the surface of two types of cells: pigment-producing cells called melanocytes and specialized bipolar cells in the light-sensitive tissue at the back of the eye (the retina).

In melanocytes, the TRPM1 channel is thought to play a role in the production of a pigment called melanin, which is the substance that gives skin, hair, and eyes their color (pigmentation). It is unclear what role the channel plays, but increased channel activity is associated with greater melanin production and darker pigmentation.

In bipolar cells, TRPM1 channels are involved in the pathway that receives visual signals from cells called rods, which are used to see in low light. This signaling is an essential step in the transmission of visual information from the eyes to the brain. In low-light conditions, visual signals from rod cells trigger the TRPM1 channels to close, which causes visual signals to be transmitted. In bright-light conditions, the TRPM1 channel is open, allowing cations to flow in and out of bipolar cells and preventing visual signals from being sent.

Does the TRPM1 gene share characteristics with other genes?

The TRPM1 gene belongs to a family of genes called TRP (transient receptor potential cation channels).

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? ( in the Handbook.

How are changes in the TRPM1 gene related to health conditions?

autosomal recessive congenital stationary night blindness - caused by mutations in the TRPM1 gene

More than 35 mutations in the TRPM1 gene have been found to cause autosomal recessive congenital stationary night blindness, which is characterized by the inability to see in low light and other vision problems such as nearsightedness (myopia). Mutations in the TRPM1 gene are found in approximately half of all people with this condition.

Most TRPM1 gene mutations change single protein building blocks (amino acids) in the TRPM1 channel and either alter the structure of the channel or prevent the channel from reaching the bipolar cell membrane. As a result, the TRPM1 channel is nonfunctional and prevents bipolar cells from relaying visual signals. The brain does not receive the visual information sent by rods, leading to difficulty seeing in low light.

Where is the TRPM1 gene located?

Cytogenetic Location: 15q13.3

Molecular Location on chromosome 15: base pairs 31,001,061 to 31,161,273

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBI (

The TRPM1 gene is located on the long (q) arm of chromosome 15 at position 13.3.

The TRPM1 gene is located on the long (q) arm of chromosome 15 at position 13.3.

More precisely, the TRPM1 gene is located from base pair 31,001,061 to base pair 31,161,273 on chromosome 15.

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

Where can I find additional information about TRPM1?

You and your healthcare professional may find the following resources about TRPM1 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 TRPM1 gene or gene products?

  • long transient receptor potential channel 1
  • LTRPC1
  • melastatin-1
  • MLSN1
  • transient receptor potential cation channel, subfamily M, member 1
  • transient receptor potential melastatin family

See How are genetic conditions and genes named? ( in the Handbook.

What glossary definitions help with understanding TRPM1?

acids ; autosomal ; autosomal recessive ; cation ; cell ; cell membrane ; channel ; congenital ; gene ; melanin ; melanocytes ; myopia ; nearsightedness ; photoreceptor ; pigment ; pigmentation ; protein ; receptor ; recessive ; retina ; rods ; tissue ; transient

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


  • Audo I, Kohl S, Leroy BP, Munier FL, Guillonneau X, Mohand-Saïd S, Bujakowska K, Nandrot EF, Lorenz B, Preising M, Kellner U, Renner AB, Bernd A, Antonio A, Moskova-Doumanova V, Lancelot ME, Poloschek CM, Drumare I, Defoort-Dhellemmes S, Wissinger B, Léveillard T, Hamel CP, Schorderet DF, De Baere E, Berger W, Jacobson SG, Zrenner E, Sahel JA, Bhattacharya SS, Zeitz C. TRPM1 is mutated in patients with autosomal-recessive complete congenital stationary night blindness. Am J Hum Genet. 2009 Nov;85(5):720-9. doi: 10.1016/j.ajhg.2009.10.013. Epub 2009 Nov 5. (
  • Devi S, Markandeya Y, Maddodi N, Dhingra A, Vardi N, Balijepalli RC, Setaluri V. Metabotropic glutamate receptor 6 signaling enhances TRPM1 calcium channel function and increases melanin content in human melanocytes. Pigment Cell Melanoma Res. 2013 May;26(3):348-56. doi: 10.1111/pcmr.12083. Epub 2013 Mar 27. (
  • Guo H, Carlson JA, Slominski A. Role of TRPM in melanocytes and melanoma. Exp Dermatol. 2012 Sep;21(9):650-4. doi: 10.1111/j.1600-0625.2012.01565.x. (
  • Koike C, Numata T, Ueda H, Mori Y, Furukawa T. TRPM1: a vertebrate TRP channel responsible for retinal ON bipolar function. Cell Calcium. 2010 Aug-Sep;48(2-3):95-101. doi: 10.1016/j.ceca.2010.08.004. Epub 2010 Sep 16. Review. (
  • Li Z, Sergouniotis PI, Michaelides M, Mackay DS, Wright GA, Devery S, Moore AT, Holder GE, Robson AG, Webster AR. Recessive mutations of the gene TRPM1 abrogate ON bipolar cell function and cause complete congenital stationary night blindness in humans. Am J Hum Genet. 2009 Nov;85(5):711-9. doi: 10.1016/j.ajhg.2009.10.003. Epub 2009 Oct 29. (
  • Nakamura M, Sanuki R, Yasuma TR, Onishi A, Nishiguchi KM, Koike C, Kadowaki M, Kondo M, Miyake Y, Furukawa T. TRPM1 mutations are associated with the complete form of congenital stationary night blindness. Mol Vis. 2010 Mar 12;16:425-37. (
  • NCBI Gene (
  • van Genderen MM, Bijveld MM, Claassen YB, Florijn RJ, Pearring JN, Meire FM, McCall MA, Riemslag FC, Gregg RG, Bergen AA, Kamermans M. Mutations in TRPM1 are a common cause of complete congenital stationary night blindness. Am J Hum Genet. 2009 Nov;85(5):730-6. doi: 10.1016/j.ajhg.2009.10.012. Epub 2009 Nov 5. (


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: January 2014
Published: February 8, 2016