Skip Navigation
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 FIG4 gene?

The official name of this gene is “FIG4 phosphoinositide 5-phosphatase.”

FIG4 is the gene's official symbol. The FIG4 gene is also known by other names, listed below.

What is the normal function of the FIG4 gene?

The FIG4 gene provides instructions for making a protein called Fig4, whose function is not well understood. Researchers believe that the Fig4 protein plays a role in regulating a compound called phosphatidylinositol-3,5-bisphosphate, or PtdIns(3,5)P(2). This compound is involved in the movement of small sac-like structures called vesicles that transport certain substances within cells (vesicle trafficking). The Fig4 protein also seems to help in the survival of nerve cells (neurons).

How are changes in the FIG4 gene related to health conditions?

Charcot-Marie-Tooth disease - caused by mutations in the FIG4 gene

At least five mutations in the FIG4 gene have been identified in individuals with Charcot-Marie-Tooth disease type 4J. One of these mutations replaces the protein building block (amino acid) isoleucine with the amino acid threonine at position 41 (written as Ile41Thr or I41T). This mutation has been identified in one copy of the FIG4 gene in everyone with Charcot-Marie-Tooth disease type 4J. In addition, each individual has another mutation in the other copy of their FIG4 gene. These mutations change single amino acids in the protein sequence or result in an abnormally short, non-functional protein. Researchers are working to determine how mutations in the FIG4 gene lead to the specific signs and symptoms of Charcot-Marie-Tooth disease type 4J.

Where is the FIG4 gene located?

Cytogenetic Location: 6q21

Molecular Location on chromosome 6: base pairs 109,691,221 to 109,825,431

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

The FIG4 gene is located on the long (q) arm of chromosome 6 at position 21.

The FIG4 gene is located on the long (q) arm of chromosome 6 at position 21.

More precisely, the FIG4 gene is located from base pair 109,691,221 to base pair 109,825,431 on chromosome 6.

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

Where can I find additional information about FIG4?

You and your healthcare professional may find the following resources about FIG4 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 FIG4 gene or gene products?

  • ALS11
  • CMT4J
  • dJ249I4.1
  • FIG4 homolog, SAC1 lipid phosphatase domain containing (S. cerevisiae)
  • FIG4 homolog (S. cerevisiae)
  • hSac3
  • KIAA0274
  • RP1-249I4.1
  • SAC3
  • Sac domain-containing inositol phosphatase 3

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

What glossary definitions help with understanding FIG4?

acids ; amino acid ; compound ; domain ; gene ; isoleucine ; lipid ; mutation ; phosphatase ; protein ; protein sequence ; sclerosis ; threonine ; vesicle

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


  • Chow CY, Landers JE, Bergren SK, Sapp PC, Grant AE, Jones JM, Everett L, Lenk GM, McKenna-Yasek DM, Weisman LS, Figlewicz D, Brown RH, Meisler MH. Deleterious variants of FIG4, a phosphoinositide phosphatase, in patients with ALS. Am J Hum Genet. 2009 Jan;84(1):85-8. doi: 10.1016/j.ajhg.2008.12.010. (
  • Chow CY, Zhang Y, Dowling JJ, Jin N, Adamska M, Shiga K, Szigeti K, Shy ME, Li J, Zhang X, Lupski JR, Weisman LS, Meisler MH. Mutation of FIG4 causes neurodegeneration in the pale tremor mouse and patients with CMT4J. Nature. 2007 Jul 5;448(7149):68-72. Epub 2007 Jun 17. (
  • Gary JD, Sato TK, Stefan CJ, Bonangelino CJ, Weisman LS, Emr SD. Regulation of Fab1 phosphatidylinositol 3-phosphate 5-kinase pathway by Vac7 protein and Fig4, a polyphosphoinositide phosphatase family member. Mol Biol Cell. 2002 Apr;13(4):1238-51. (
  • Gene Review: Charcot-Marie-Tooth Neuropathy Type 4 (
  • Jones AL, Quimby BB, Hood JK, Ferrigno P, Keshava PH, Silver PA, Corbett AH. SAC3 may link nuclear protein export to cell cycle progression. Proc Natl Acad Sci U S A. 2000 Mar 28;97(7):3224-9. (
  • NCBI Gene (
  • Zhang X, Chow CY, Sahenk Z, Shy ME, Meisler MH, Li J. Mutation of FIG4 causes a rapidly progressive, asymmetric neuronal degeneration. Brain. 2008 Aug;131(Pt 8):1990-2001. doi: 10.1093/brain/awn114. Epub 2008 Jun 12. (


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