SCN9A
protein-codingsodium voltage-gated channel alpha subunit 9, the group of Sodium voltage-gated channel alpha subunits
Gene summary
This gene encodes a voltage-gated sodium channel which plays a significant role in nociception signaling. Mutations in this gene have been associated with primary erythermalgia, channelopathy-associated insensitivity to pain, and paroxysmal extreme pain disorder. [provided by RefSeq, Aug 2009]
MANE transcript
Inheritance
ClinVar variants
Top phenotype
gnomAD constraint
Max pathogenic AF
Genomic locus
External References & Databases
Transcript & Mutation Effects
hg38 • Region Span ~180.8 kbGenCC Phenotypes & Disease Associations
Curated gene-disease validity assertions and inheritance patterns
Inheritance Pattern: AD
Disease ID:MONDO:0007571
Submitter: G2P
Inheritance Pattern: AD
Disease ID:MONDO:0005027
Submitter: ClinGen
Variants in SCN9A have been observed in individuals with a variety of primarily neuropathy phenotypes, including autosomal dominant small fiber neuropathy and erythermalgia and autosomal recessive congenital insensitivity to pain. A relationship between SCN9A and autosomal dominant epilepsy (MONDO:0005027) has also been reported, which is the focus of this recuration. The SCN9A gene was initially curated by the ClinGen Epilepsy Gene Curation Expert Panel (GCEP) in relation to autosomal dominant epilepsy on 6/5/2018. At the time, this gene-disease relationship was classified as LIMITED based on case-level data. Since that time, a publication providing evidence to refute this gene-disease relationship has become available. In the initial curation, the primary evidence supporting a gene-disease relationship with epilepsy was provided from Singh et al. 2009 (PMID 19763161). This publication described a large family segregating the p.Asn641Tyr SCN9A variant in individuals with febrile or afebrile seizures, primarily limited to childhood. Additionally, this publication provided weak experimental evidence with a homozygous p.Asn641Tyr knock-in mouse model. A recent publication by Fasham et al. 2020 (PMID 33216760) provides evidence to refute the pathogenicity of the p.Asn641Tyr variant. In this publication, the p.Asn641Tyr variant was identified in an Amish proband with a de novo CHD4 variant, consistent with the proband phenotype; the SCN9A variant was shown to be inherited from the proband’s unaffected father. The p.Asn641Tyr variant was subsequently identified in another 7 Amish families where it was transmitted through an additional minimum 26 constitutive gene carriers and presumed to be transmitted to hundreds of additional offspring, only one of whom had any reported seizures. Additionally, the p.Asn641Tyr variant is present in 6 alleles in the gnomAD database. Additional variants in SCN9A have been reported in the literature in association with epilepsy and are summarized in this recuration, but the majority are unable to be scored due to lack of segregation with disease, high minor allele frequency in general population databases or an alternate molecular explanation for disease. Case level data provides a score of 0.4 points and there is no scored experimental evidence, resulting in a total score of 0.4 points. In summary, there is convincing evidence refuting the relationship between SCN9A and autosomal dominant epilepsy, which significantly outweighs the evidence supporting the relationship. This classification was approved by the ClinGen Epilepsy GCEP on 2/5/21 (SOP Version 8).
Inheritance Pattern: AR
Disease ID:MONDO:0009459
Submitter: Laboratory for Molecular Medicine
This gene-disease relationship has undergone rapid assessment. Classifications are based on preliminary review of gene-disease validity during analysis of genomic sequencing results.
Inheritance Pattern: AD
Disease ID:MONDO:0005027
Submitter: Illumina
Inheritance Pattern: AD
Disease ID:MONDO:0013470
Submitter: Labcorp Genetics (formerly Invitae)
Inheritance Pattern: AD
Disease ID:MONDO:0008179
Submitter: Labcorp Genetics (formerly Invitae)
Inheritance Pattern: SD
Disease ID:MONDO:0020127
Submitter: PanelApp Australia
Inheritance Pattern: AD
Disease ID:MONDO:0005027
Submitter: PanelApp Australia
Inheritance Pattern: AD
Disease ID:MONDO:0007571
Submitter: Genomics England PanelApp
Inheritance Pattern: SD
Disease ID:MONDO:0009459
Submitter: Ambry Genetics
Inheritance Pattern: AD
Disease ID:MONDO:0013470
Submitter: Ambry Genetics
Inheritance Pattern: AD
Disease ID:MONDO:0017629
Submitter: Orphanet
Inheritance Pattern: AD
Disease ID:MONDO:0009459
Submitter: Orphanet
Inheritance Pattern: AD
Disease ID:MONDO:0007571
Submitter: Orphanet
Inheritance Pattern: AR
Disease ID:MONDO:0019941
Submitter: Orphanet
Inheritance Pattern: AD
Disease ID:MONDO:0008179
Submitter: Orphanet
Inheritance Pattern: AR
Disease ID:MONDO:0009459
Submitter: Labcorp Genetics (formerly Invitae)
Clinical Genomic Database (CGD)
Manifestation: Dermatologic; Neurologic
Intervention: Neurologic
Rationale: In Primary erythermalgia, medical treatment (with specific sodium channel blocking agents such as XEN402) has been reported as beneficial; Individuals with Paroxysmal extreme pain disorder have been reported as responding to medical therapy (eg, carbamazepine) in terms of clinical manifestations (attacks of pain) as well as psychomotor development in some
Comments: Many treatments have been attempted (with inconsistent success) in Erythermalgia, primary, and some have been described by patients as providing subjective relief from symptoms; Indifference to pain, congenital, can result in injuries, some of which may in theory be preventable with early diagnosis and preventive measures
ClinVar Associated Diseases & Phenotypes
Reported disease conditions connected to SCN9A variants in ClinVar
ClinVar Variants & Pathogenicity by Type
Statistics based on transcript NM_001365536.1. Only rare variants are included.
We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.
Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.
| Effect | PathogenicP | Likely pathogenicLP | VUS | Likely benignLB | BenignB | Sum |
|---|---|---|---|---|---|---|
| synonymous | 1 | 24 | 585 | 13 | 623 | |
| missense | 18 | 17 | 1653 | 94 | 5 | 1787 |
| nonsense | 41 | 17 | 8 | 66 | ||
| start loss | 0 | |||||
| frameshift | 49 | 16 | 17 | 82 | ||
| splice donor/acceptor (+/-2bp) | 6 | 30 | 6 | 42 | ||
| Total | 114 | 81 | 1708 | 679 | 18 | 2600 |
Highest pathogenic variant AF is 0.00004091658
Transcript Catalog
Annotated transcript isoforms across RefSeq and Ensembl databases
| Transcript ID | Source | Protein ID | Coding Exons | MANE Status |
|---|---|---|---|---|
| RefSeq | NP_001352465.1 | 26 | MANE Select | |
| Ensembl | ENSP00000495601.1 | 26 | MANE Select | |
| RefSeq | NP_002968.2 | 26 | Standard | |
| Ensembl | ENSP00000304748.7 | 26 | Standard |
Gene Ontology (GO) Annotations & Pathways
Biological processes, molecular functions, cellular components and pathways
Pathways ConsensusPathDB
- Taste transduction - Homo sapiens (human)
- Developmental Biology
- Phase 0 - rapid depolarisation
- Cardiac conduction
- Muscle contraction
Biological Process
- sodium ion transport
- inflammatory response
- response to toxic substance
- post-embryonic development
- neuronal action potential
Molecular Function
- voltage-gated ion channel activity
- voltage-gated sodium channel activity
- sodium ion binding
Cellular Component
- voltage-gated sodium channel complex
- plasma membrane
- integral component of plasma membrane
- axon
gnomAD Constraint
Source:
- Gene type
- protein_coding
- Transcript type
- protein_coding
- Transcript
- ENST00000409672
- Coding exons
- 26
- Length
- 180809
- Individuals with no LoFs
- 125635
- Homozygous LoFs
- 0
- Heterozygous LoFs
- 113
- Defined
- 125748
- p
- 0.000449
| Z-Score | Observed | Expected | Observed/Expected | Mutation Rate | Total Possible | |
|---|---|---|---|---|---|---|
| Missense | 1.06 | 913 | 1.01e+3 | 0.906 | 0.0000524 | 13101 |
| Missense (PolyPhen) | 343 | 453.44 | 0.75643 | 6036 | ||
| Synonymous | -1.08 | 377 | 351 | 1.07 | 0.0000183 | 3627 |
| Loss of Function | 3.70 | 43 | 78.3 | 0.549 | 0.00000424 | 1050 |
Population LoF Frequency
| Population | CAF | p-value | Status |
|---|---|---|---|
| African | 0.00084 | 0.00080 | rare |
| Latino/Admixed American | 0.00066 | 0.00064 | rare |
| Ashkenazi Jewish | 0.000099 | 0.000099 | rare |
| East Asian | 0.0015 | 0.0015 | notable |
| Finnish | 0.000046 | 0.000046 | rare |
| European (Non-Finnish) | 0.00037 | 0.00036 | rare |
| South Asian | 0.00020 | 0.00020 | rare |
| Other | 0.00033 | 0.00016 | rare |
dbNSFP Gene Annotations
Source:
- Function
- FUNCTION: Mediates the voltage-dependent sodium ion permeability of excitable membranes. Assuming opened or closed conformations in response to the voltage difference across the membrane, the protein forms a sodium-selective channel through which Na(+) ions may pass in accordance with their electrochemical gradient (PubMed:7720699, PubMed:17167479, PubMed:25240195, PubMed:26680203, PubMed:15385606, PubMed:16988069, PubMed:17145499, PubMed:19369487, PubMed:24311784). It is a tetrodotoxin-sensitive Na(+) channel isoform (PubMed:7720699). Plays a role in pain mechanisms, especially in the development of inflammatory pain (PubMed:17167479, PubMed:17145499, PubMed:19369487, PubMed:24311784). {ECO:0000269|PubMed:15178348, ECO:0000269|PubMed:15385606, ECO:0000269|PubMed:16988069, ECO:0000269|PubMed:17145499, ECO:0000269|PubMed:17167479, ECO:0000269|PubMed:19369487, ECO:0000269|PubMed:24311784, ECO:0000269|PubMed:25240195, ECO:0000269|PubMed:26680203, ECO:0000269|PubMed:7720699}.;
- Disease
- DISEASE: Primary erythermalgia (PERYTHM) [MIM:133020]: Autosomal dominant disease characterized by recurrent episodes of severe pain associated with redness and warmth in the feet or hands. {ECO:0000269|PubMed:14985375, ECO:0000269|PubMed:15385606, ECO:0000269|PubMed:15955112, ECO:0000269|PubMed:15958509, ECO:0000269|PubMed:16216943, ECO:0000269|PubMed:16392115, ECO:0000269|PubMed:16702558, ECO:0000269|PubMed:16988069, ECO:0000269|PubMed:18945915, ECO:0000269|PubMed:19369487, ECO:0000269|PubMed:24311784}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Indifference to pain, congenital, autosomal recessive (CIP) [MIM:243000]: A disorder characterized by congenital inability to perceive any form of pain, in any part of the body. All other sensory modalities are preserved and the peripheral and central nervous systems are apparently intact. Patients perceive the sensations of touch, warm and cold temperature, proprioception, tickle and pressure, but not painful stimuli. There is no evidence of a motor or sensory neuropathy, either axonal or demyelinating. {ECO:0000269|PubMed:20635406}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Paroxysmal extreme pain disorder (PEPD) [MIM:167400]: Autosomal dominant paroxysmal disorder of pain and autonomic dysfunction. The distinctive features are paroxysmal episodes of burning pain in the rectal, ocular, and mandibular areas accompanied by autonomic manifestations such as skin flushing. {ECO:0000269|PubMed:17145499, ECO:0000269|PubMed:18945915, ECO:0000269|PubMed:25285947}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Generalized epilepsy with febrile seizures plus 7 (GEFS+7) [MIM:613863]: A rare autosomal dominant, familial condition with incomplete penetrance and large intrafamilial variability. Patients display febrile seizures persisting sometimes beyond the age of 6 years and/or a variety of afebrile seizure types. This disease combines febrile seizures, generalized seizures often precipitated by fever at age 6 years or more, and partial seizures, with a variable degree of severity. {ECO:0000269|PubMed:19763161}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Febrile seizures, familial, 3B (FEB3B) [MIM:613863]: Seizures associated with febrile episodes in childhood without any evidence of intracranial infection or defined pathologic or traumatic cause. It is a common condition, affecting 2-5% of children aged 3 months to 5 years. The majority are simple febrile seizures (generally defined as generalized onset, single seizures with a duration of less than 30 minutes). Complex febrile seizures are characterized by focal onset, duration greater than 30 minutes, and/or more than one seizure in a 24 hour period. The likelihood of developing epilepsy following simple febrile seizures is low. Complex febrile seizures are associated with a moderately increased incidence of epilepsy. {ECO:0000269|PubMed:19763161}. Note=The disease is caused by mutations affecting the gene represented in this entry.;
Recessive Scores
- pRec
- 0.199
Intolerance Scores
- LoFtool
- 0.0121
- RVIS EVS
- 0.33
- RVIS percentile EVS
- 73.63
Essentials
- Essential (CRISPR)
- N
- Essential (CRISPR2)
- N
- Essential (gene trap)
- N
- Indispensability pred.
- N
- Indispensability score
- 0.179
Gene Damage Prediction
| All | Recessive | Dominant | |
|---|---|---|---|
| Mendelian | Medium | Medium | Medium |
| Primary Immunodeficiency | Medium | Medium | High |
| Cancer | Medium | Medium | Medium |