Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: https://medlineplus.gov/genetics/gene/scn2a/

SCN2A gene

sodium voltage-gated channel alpha subunit 2

Normal Function

The SCN2A gene belongs to a family of genes that provide instructions for making sodium channels. These channels, which transport positively charged atoms (ions) of sodium into cells, play a key role in a cell's ability to generate and transmit electrical signals.

The SCN2A gene provides instructions for making one part (the alpha subunit) of a sodium channel called NaV1.2. These channels are primarily found in the brain, where they control the flow of sodium ions into nerve cells (neurons). NaV1.2 channels are involved in transmitting signals from one neuron to another. Communication between neurons depends on chemicals called neurotransmitters, which are released from one neuron and taken up by neighboring neurons. The flow of sodium ions through NaV1.2 channels helps determine when neurotransmitters will be released.

Health Conditions Related to Genetic Changes

Epilepsy of infancy with migrating focal seizures

Variants (also called mutations) in the SCN2A gene can cause epilepsy of infancy with migrating focal seizures (EIMFS). This condition is typically characterized by recurrent seizures that begin before the age of 6 months. Affected individuals often have significant developmental delays.

Most SCN2A variants that cause EIMFS lead to a substitution of one protein building block (amino acid) for another in the SCN2A protein. Researchers are working to learn more about the ways in which specific SCN2A gene variants can affect the activity of sodium channels in the brain and how this change in activity results in the repeated seizures seen in children with EIMFS.

More About This Health Condition

Autism spectrum disorder

MedlinePlus Genetics provides information about Autism spectrum disorder

More About This Health Condition

Episodic ataxia

MedlinePlus Genetics provides information about Episodic ataxia

More About This Health Condition

Genetic epilepsy with febrile seizures plus

MedlinePlus Genetics provides information about Genetic epilepsy with febrile seizures plus

More About This Health Condition

Other disorders

Variants in the SCN2A gene are associated with SCN2A-developmental and epileptic encephalopathy. Developmental and epileptic encephalopathies (DEEs) are a group of disorders that are characterized by developmental delays and seizures that typically begin early in life and are often difficult to treat. Additional signs and symptoms seen in children with SCN2A-developmental and epileptic encephalopathy can include low muscle tone (hypotonia), difficulty feeding, behavioral disorders, abnormal movements, and intellectual disabilities. Affected individuals may experience different types of seizures and may receive an additional epilepsy diagnosis based on the specific seizure type. 

Variants in the SCN2A gene have also been associated with benign familial infantile seizures (BFIE), also called self-limited infantile epilepsy (SeLIE). Babies with BFIE usually begin having seizures between the ages of 3 and 20 months. In most affected individuals, development is normal. Seizures can typically be managed with medication and usually stop about a year after they begin.

Other Names for This Gene

  • NAC2
  • NAV1.2
  • SCN2A1
  • SCN2A2
  • sodium channel, brain type II, alpha subunit
  • sodium channel, voltage gated, type II alpha subunit
  • sodium channel, voltage-gated, type II, alpha 1 polypeptide
  • sodium channel, voltage-gated, type II, alpha 2 polypeptide
  • sodium channel, voltage-gated, type II, alpha subunit
  • sodium voltage-gated channel, alpha subunit 2

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases

References

  • Howell KB, McMahon JM, Carvill GL, Tambunan D, Mackay MT, Rodriguez-Casero V, Webster R, Clark D, Freeman JL, Calvert S, Olson HE, Mandelstam S, Poduri A, Mefford HC, Harvey AS, Scheffer IE. SCN2A encephalopathy: A major cause of epilepsy of infancy with migrating focal seizures. Neurology. 2015 Sep 15;85(11):958-66. doi: 10.1212/WNL.0000000000001926. Epub 2015 Aug 19. Citation on PubMed
  • Thompson CH, Potet F, Abramova TV, DeKeyser JM, Ghabra NF, Vanoye CG, Millichap JJ, George AL. Epilepsy-associated SCN2A (NaV1.2) variants exhibit diverse and complex functional properties. J Gen Physiol. 2023 Oct 2;155(10):e202313375. doi: 10.1085/jgp.202313375. Epub 2023 Aug 14. Citation on PubMed
  • Yang XR, Ginjupalli VKM, Theriault O, Poulin H, Appendino JP, Au PYB, Chahine M. SCN2A-related epilepsy of infancy with migrating focal seizures: report of a variant with apparent gain- and loss-of-function effects. J Neurophysiol. 2022 May 1;127(5):1388-1397. doi: 10.1152/jn.00309.2021. Epub 2022 Apr 13. Citation on PubMed
  • Zeng Q, Yang Y, Duan J, Niu X, Chen Y, Wang D, Zhang J, Chen J, Yang X, Li J, Yang Z, Jiang Y, Liao J, Zhang Y. SCN2A-Related Epilepsy: The Phenotypic Spectrum, Treatment and Prognosis. Front Mol Neurosci. 2022 Mar 30;15:809951. doi: 10.3389/fnmol.2022.809951. eCollection 2022. Citation on PubMed

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.