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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 2016

What is the official name of the SLC52A3 gene?

The official name of this gene is “solute carrier family 52 (riboflavin transporter), member 3.”

SLC52A3 is the gene's official symbol. The SLC52A3 gene is also known by other names, listed below.

What is the normal function of the SLC52A3 gene?

The SLC52A3 gene (previously called the C20orf54 gene) provides instructions for making a riboflavin transporter protein called RFVT3 (formerly known as RFT2). This protein moves (transports) a vitamin called riboflavin (also called vitamin B2) across the cell membrane. Riboflavin cannot be made by the body, so it must be obtained from the food a person eats. The RFVT3 protein is found at especially high levels in cells of the small intestine and is important for absorbing riboflavin during digestion so that the vitamin can be used in the body.

In the cells of the body, riboflavin is the core component of molecules called flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). These molecules function as coenzymes, which means they help enzymes carry out chemical reactions. FAD and FMN are involved in many different chemical reactions and are required for a variety of cellular processes. One important role of these coenzymes is in the production of energy for cells. FAD and FMN are also involved in the breakdown (metabolism) of carbohydrates, fats, and proteins.

Does the SLC52A3 gene share characteristics with other genes?

The SLC52A3 gene belongs to a family of genes called SLC (solute carriers).

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 SLC52A3 gene related to health conditions?

riboflavin transporter deficiency neuronopathy - caused by mutations in the SLC52A3 gene

More than two dozen mutations in the SLC52A3 gene have been found to cause riboflavin transporter deficiency neuronopathy. This neurological condition encompasses two disorders that were previously considered to be separate: Brown-Vialetto-Van Laere syndrome and Fazio-Londe disease. The gene mutations involved in this condition lead to production of abnormal RFVT3 proteins. Some mutations lead to the production of an altered protein that cannot get to the cell membrane, so it is unable to transport riboflavin into the cell. Other mutations lead to a version of the protein that can get to the cell membrane, but its function as a transporter is impaired. These changes impair the absorption of riboflavin in the small intestine. The resulting shortage of riboflavin leads to a reduction of FAD and FMN. However, it is unclear how these changes lead to the nerve problems that cause hearing loss, muscle weakness in the face and limbs, and breathing problems in people with the disorder.

Where is the SLC52A3 gene located?

Cytogenetic Location: 20p13

Molecular Location on chromosome 20: base pairs 760,080 to 775,985

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

The SLC52A3 gene is located on the short (p) arm of chromosome 20 at position 13.

The SLC52A3 gene is located on the short (p) arm of chromosome 20 at position 13.

More precisely, the SLC52A3 gene is located from base pair 760,080 to base pair 775,985 on chromosome 20.

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

Where can I find additional information about SLC52A3?

You and your healthcare professional may find the following resources about SLC52A3 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 SLC52A3 gene or gene products?

  • bA371L19.1
  • C20orf54
  • hRFT2
  • MGC10698
  • RFT2
  • RFVT3
  • riboflavin transporter 2
  • solute carrier family 52, riboflavin transporter, member 3

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

What glossary definitions help with understanding SLC52A3?

adenine ; breakdown ; carrier ; cell ; cell membrane ; deficiency ; digestion ; gene ; intestine ; metabolism ; neurological ; protein ; solute ; syndrome

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


  • Bosch AM, Abeling NG, Ijlst L, Knoester H, van der Pol WL, Stroomer AE, Wanders RJ, Visser G, Wijburg FA, Duran M, Waterham HR. Brown-Vialetto-Van Laere and Fazio Londe syndrome is associated with a riboflavin transporter defect mimicking mild MADD: a new inborn error of metabolism with potential treatment. J Inherit Metab Dis. 2011 Feb;34(1):159-64. doi: 10.1007/s10545-010-9242-z. Epub 2010 Nov 26. (
  • Dipti S, Childs AM, Livingston JH, Aggarwal AK, Miller M, Williams C, Crow YJ. Brown-Vialetto-Van Laere syndrome; variability in age at onset and disease progression highlighting the phenotypic overlap with Fazio-Londe disease. Brain Dev. 2005 Sep;27(6):443-6. Epub 2004 Dec 15. (
  • Gene Review: Riboflavin Transporter Deficiency Neuronopathy (
  • Green P, Wiseman M, Crow YJ, Houlden H, Riphagen S, Lin JP, Raymond FL, Childs AM, Sheridan E, Edwards S, Josifova DJ. Brown-Vialetto-Van Laere syndrome, a ponto-bulbar palsy with deafness, is caused by mutations in c20orf54. Am J Hum Genet. 2010 Mar 12;86(3):485-9. doi: 10.1016/j.ajhg.2010.02.006. Epub 2010 Mar 4. (
  • McShane MA, Boyd S, Harding B, Brett EM, Wilson J. Progressive bulbar paralysis of childhood. A reappraisal of Fazio-Londe disease. Brain. 1992 Dec;115 ( Pt 6):1889-900. (
  • Nabokina SM, Subramanian VS, Said HM. Effect of clinical mutations on functionality of the human riboflavin transporter-2 (hRFT-2). Mol Genet Metab. 2012 Apr;105(4):652-7. doi: 10.1016/j.ymgme.2011.12.021. Epub 2012 Jan 5. (
  • NCBI Gene (
  • Subramanian VS, Subramanya SB, Rapp L, Marchant JS, Ma TY, Said HM. Differential expression of human riboflavin transporters -1, -2, and -3 in polarized epithelia: a key role for hRFT-2 in intestinal riboflavin uptake. Biochim Biophys Acta. 2011 Dec;1808(12):3016-21. doi: 10.1016/j.bbamem.2011.08.004. Epub 2011 Aug 11. (
  • Yonezawa A, Inui K. Novel riboflavin transporter family RFVT/SLC52: identification, nomenclature, functional characterization and genetic diseases of RFVT/SLC52. Mol Aspects Med. 2013 Apr-Jun;34(2-3):693-701. doi: 10.1016/j.mam.2012.07.014. 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 2016
Published: February 8, 2016