rs371914255

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_ModerateBP6BP7BS1

The NM_000334.4(SCN4A):​c.2478C>T​(p.Ile826Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00018 in 1,584,018 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00082 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

SCN4A
NM_000334.4 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:7

Conservation

PhyloP100: -1.94

Publications

1 publications found
Variant links:
Genes affected
SCN4A (HGNC:10591): (sodium voltage-gated channel alpha subunit 4) Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with 24 transmembrane domains and one or more regulatory beta subunits. They are responsible for the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family. It is expressed in skeletal muscle, and mutations in this gene have been linked to several myotonia and periodic paralysis disorders. [provided by RefSeq, Jul 2008]
SCN4A Gene-Disease associations (from GenCC):
  • hyperkalemic periodic paralysis
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Orphanet
  • paramyotonia congenita of Von Eulenburg
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Orphanet
  • SCN4A-related myopathy, autosomal recessive
    Inheritance: AR Classification: DEFINITIVE Submitted by: Illumina, ClinGen
  • hypokalemic periodic paralysis, type 2
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • potassium-aggravated myotonia
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • congenital myasthenic syndrome 16
    Inheritance: AR Classification: STRONG, LIMITED Submitted by: PanelApp Australia, Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • congenital myopathy
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
  • congenital myopathy 22A, classic
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • acetazolamide-responsive myotonia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • hypokalemic periodic paralysis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myotonia fluctuans
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myotonia permanens
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • postsynaptic congenital myasthenic syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -8 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.36).
BP6
Variant 17-63951799-G-A is Benign according to our data. Variant chr17-63951799-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 194331.
BP7
Synonymous conserved (PhyloP=-1.94 with no splicing effect.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000821 (125/152308) while in subpopulation AFR AF = 0.00248 (103/41574). AF 95% confidence interval is 0.00209. There are 0 homozygotes in GnomAd4. There are 55 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN4ANM_000334.4 linkc.2478C>T p.Ile826Ile synonymous_variant Exon 14 of 24 ENST00000435607.3 NP_000325.4 P35499

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN4AENST00000435607.3 linkc.2478C>T p.Ile826Ile synonymous_variant Exon 14 of 24 1 NM_000334.4 ENSP00000396320.1 P35499

Frequencies

GnomAD3 genomes
AF:
0.000815
AC:
124
AN:
152190
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00246
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000327
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00212
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.000958
GnomAD2 exomes
AF:
0.000348
AC:
70
AN:
200992
AF XY:
0.000324
show subpopulations
Gnomad AFR exome
AF:
0.00209
Gnomad AMR exome
AF:
0.0000689
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00268
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000458
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000112
AC:
160
AN:
1431710
Hom.:
0
Cov.:
32
AF XY:
0.000103
AC XY:
73
AN XY:
709404
show subpopulations
African (AFR)
AF:
0.00234
AC:
77
AN:
32856
American (AMR)
AF:
0.0000999
AC:
4
AN:
40060
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25604
East Asian (EAS)
AF:
0.00110
AC:
42
AN:
38148
South Asian (SAS)
AF:
0.0000365
AC:
3
AN:
82136
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50690
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5738
European-Non Finnish (NFE)
AF:
0.00000911
AC:
10
AN:
1097130
Other (OTH)
AF:
0.000404
AC:
24
AN:
59348
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.497
Heterozygous variant carriers
0
10
20
29
39
49
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000821
AC:
125
AN:
152308
Hom.:
0
Cov.:
32
AF XY:
0.000738
AC XY:
55
AN XY:
74480
show subpopulations
African (AFR)
AF:
0.00248
AC:
103
AN:
41574
American (AMR)
AF:
0.000327
AC:
5
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00212
AC:
11
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68018
Other (OTH)
AF:
0.000948
AC:
2
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000433
Hom.:
0
Bravo
AF:
0.00114
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:1
Jun 05, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 23, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Familial hyperkalemic periodic paralysis Benign:2
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Congenital myasthenic syndrome 16 Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Hypokalemic periodic paralysis, type 2 Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Paramyotonia congenita of Von Eulenburg Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

SCN4A-related disorder Benign:1
Aug 15, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Potassium-aggravated myotonia Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.36
CADD
Benign
2.8
DANN
Benign
0.81
PhyloP100
-1.9

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs371914255; hg19: chr17-62029159; COSMIC: COSV71125696; COSMIC: COSV71125696; API