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


Reviewed January 2010

What is the official name of the PRX gene?

The official name of this gene is “periaxin.”

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

What is the normal function of the PRX gene?

The PRX gene provides instructions for making a protein called periaxin. Periaxin is required for the maintenance of myelin, the protective substance that covers nerves and promotes the efficient transmission of nerve impulses. The exact function of periaxin is unclear, but research suggests that it helps stabilize myelin.

The PRX gene produces two forms of periaxin, called long (L) and short (S) because they differ in size. Research studies show that the short form (S-periaxin) is distributed throughout the cytoplasm, the fluid inside cells. The long form (L-periaxin) is concentrated initially in the nucleus, then relocates to the cell membrane during the formation of myelin. L- and S-periaxin probably have slightly different functions, based on their different cell locations.

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

Charcot-Marie-Tooth disease - caused by mutations in the PRX gene

Researchers have identified at least 10 PRX gene mutations that cause a form of Charcot-Marie-Tooth disease known as type 4F (sometimes called Dejerine-Sottas syndrome). These mutations result in an abnormally short L-periaxin protein that cannot maintain the myelin structure. Disrupted myelin structure can lead to the loss of myelin (demyelination) and impaired transmission of nerve impulses. As a result, peripheral nerves are less able to activate muscles used for movement or relay information from sensory cells back to the brain. These peripheral nerve abnormalities cause the signs and symptoms of type 4F Charcot-Marie-Tooth disease.

Where is the PRX gene located?

Cytogenetic Location: 19q13.2

Molecular Location on chromosome 19: base pairs 40,393,764 to 40,414,718

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

The PRX gene is located on the long (q) arm of chromosome 19 at position 13.2.

The PRX gene is located on the long (q) arm of chromosome 19 at position 13.2.

More precisely, the PRX gene is located from base pair 40,393,764 to base pair 40,414,718 on chromosome 19.

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

Where can I find additional information about PRX?

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

  • KIAA1620

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

What glossary definitions help with understanding PRX?

cell ; cell membrane ; cytoplasm ; demyelination ; gene ; nucleus ; peripheral ; peripheral nerves ; protein ; sensory cells ; syndrome

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


  • Auer-Grumbach M, Fischer C, Papić L, John E, Plecko B, Bittner RE, Bernert G, Pieber TR, Miltenberger G, Schwarz R, Windpassinger C, Grill F, Timmerman V, Speicher MR, Janecke AR. Two novel mutations in the GDAP1 and PRX genes in early onset Charcot-Marie-Tooth syndrome. Neuropediatrics. 2008 Feb;39(1):33-8. doi: 10.1055/s-2008-1077085. (
  • Baránková L, Sisková D, Hühne K, Vyhnálková E, Sakmaryová I, Bojar M, Rautenstrauss B, Seeman P. A 71-nucleotide deletion in the periaxin gene in a Romani patient with early-onset slowly progressive demyelinating CMT. Eur J Neurol. 2008 Jun;15(6):548-51. doi: 10.1111/j.1468-1331.2008.02104.x. Epub 2008 Apr 8. (
  • Boerkoel CF, Takashima H, Stankiewicz P, Garcia CA, Leber SM, Rhee-Morris L, Lupski JR. Periaxin mutations cause recessive Dejerine-Sottas neuropathy. Am J Hum Genet. 2001 Feb;68(2):325-33. Epub 2000 Dec 15. Erratum in: Am J Hum Genet 2001 Feb;68(2):557. (
  • Gene Review: Charcot-Marie-Tooth Neuropathy Type 4 (
  • Guilbot A, Williams A, Ravisé N, Verny C, Brice A, Sherman DL, Brophy PJ, LeGuern E, Delague V, Bareil C, Mégarbané A, Claustres M. A mutation in periaxin is responsible for CMT4F, an autosomal recessive form of Charcot-Marie-Tooth disease. Hum Mol Genet. 2001 Feb 15;10(4):415-21. (
  • Kabzinska D, Drac H, Sherman DL, Kostera-Pruszczyk A, Brophy PJ, Kochanski A, Hausmanowa-Petrusewicz I. Charcot-Marie-Tooth type 4F disease caused by S399fsx410 mutation in the PRX gene. Neurology. 2006 Mar 14;66(5):745-7. (
  • Kabzinska D, Hausmanowa-Petrusewicz I, Kochanski A. Charcot-Marie-Tooth disorders with an autosomal recessive mode of inheritance. Clin Neuropathol. 2008 Jan-Feb;27(1):1-12. Review. (
  • Kijima K, Numakura C, Shirahata E, Sawaishi Y, Shimohata M, Igarashi S, Tanaka T, Hayasaka K. Periaxin mutation causes early-onset but slow-progressive Charcot-Marie-Tooth disease. J Hum Genet. 2004;49(7):376-9. Epub 2004 Jun 12. (
  • NCBI Gene (
  • Niemann A, Berger P, Suter U. Pathomechanisms of mutant proteins in Charcot-Marie-Tooth disease. Neuromolecular Med. 2006;8(1-2):217-42. Review. (
  • Otagiri T, Sugai K, Kijima K, Arai H, Sawaishi Y, Shimohata M, Hayasaka K. Periaxin mutation in Japanese patients with Charcot-Marie-Tooth disease. J Hum Genet. 2006;51(7):625-8. Epub 2006 Jun 13. (
  • Takashima H, Boerkoel CF, De Jonghe P, Ceuterick C, Martin JJ, Voit T, Schröder JM, Williams A, Brophy PJ, Timmerman V, Lupski JR. Periaxin mutations cause a broad spectrum of demyelinating neuropathies. Ann Neurol. 2002 Jun;51(6):709-15. (
  • Vallat JM, Tazir M, Magdelaine C, Sturtz F, Grid D. Autosomal-recessive Charcot-Marie-Tooth diseases. J Neuropathol Exp Neurol. 2005 May;64(5):363-70. Review. (
  • Young P, Suter U. The causes of Charcot-Marie-Tooth disease. Cell Mol Life Sci. 2003 Dec;60(12):2547-60. Review. (


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 2010
Published: February 1, 2016