NM_000334.4:c.2824G>A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_000334.4(SCN4A):​c.2824G>A​(p.Asp942Asn) variant causes a missense change. The variant allele was found at a frequency of 0.0000909 in 1,605,498 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D942G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000090 ( 0 hom. )

Consequence

SCN4A
NM_000334.4 missense

Scores

7
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 4.00

Publications

2 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: Likely_benign. The variant received -1 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 97 curated pathogenic missense variants (we use a threshold of 10). The gene has 19 curated benign missense variants. Gene score misZ: 1.5606 (below the threshold of 3.09). Trascript score misZ: 2.2224 (below the threshold of 3.09). GenCC associations: The gene is linked to congenital myasthenic syndrome 16, paramyotonia congenita of Von Eulenburg, hyperkalemic periodic paralysis, hypokalemic periodic paralysis, type 2, congenital myopathy, hypokalemic periodic paralysis, SCN4A-related myopathy, autosomal recessive, congenital myopathy 22A, classic, potassium-aggravated myotonia, postsynaptic congenital myasthenic syndrome, myotonia fluctuans, myotonia permanens, acetazolamide-responsive myotonia.
BP4
Computational evidence support a benign effect (MetaRNN=0.23458636).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN4ANM_000334.4 linkc.2824G>A p.Asp942Asn missense_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.2824G>A p.Asp942Asn missense_variant Exon 14 of 24 1 NM_000334.4 ENSP00000396320.1 P35499

Frequencies

GnomAD3 genomes
AF:
0.0000986
AC:
15
AN:
152088
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000314
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000524
AC:
13
AN:
247902
AF XY:
0.0000372
show subpopulations
Gnomad AFR exome
AF:
0.000323
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000557
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000445
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000901
AC:
131
AN:
1453410
Hom.:
0
Cov.:
32
AF XY:
0.0000957
AC XY:
69
AN XY:
721200
show subpopulations
African (AFR)
AF:
0.000301
AC:
10
AN:
33274
American (AMR)
AF:
0.00
AC:
0
AN:
44494
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25952
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39466
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86056
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53282
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5740
European-Non Finnish (NFE)
AF:
0.000106
AC:
117
AN:
1105164
Other (OTH)
AF:
0.0000333
AC:
2
AN:
59982
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
7
14
21
28
35
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000986
AC:
15
AN:
152088
Hom.:
0
Cov.:
32
AF XY:
0.000121
AC XY:
9
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.000314
AC:
13
AN:
41398
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68004
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.000132
Hom.:
0
Bravo
AF:
0.0000869
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ExAC
AF:
0.0000579
AC:
7
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jan 27, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2824G>A (p.D942N) alteration is located in exon 14 (coding exon 14) of the SCN4A gene. This alteration results from a G to A substitution at nucleotide position 2824, causing the aspartic acid (D) at amino acid position 942 to be replaced by an asparagine (N). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Paramyotonia congenita of Von Eulenburg;C0238357:Familial hyperkalemic periodic paralysis;C2750061:Hypokalemic periodic paralysis, type 2;C2931826:Potassium-aggravated myotonia;C3280112:Congenital myasthenic syndrome 16;C5830453:Congenital myopathy 22A, classic;C5830501:Congenital myopathy 22B, severe fetal Uncertain:1
Apr 23, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Sep 16, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Familial hyperkalemic periodic paralysis Uncertain:1
Sep 04, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 942 of the SCN4A protein (p.Asp942Asn). This variant is present in population databases (rs761589948, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with SCN4A-related conditions. ClinVar contains an entry for this variant (Variation ID: 477409). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt SCN4A protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.41
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.28
T
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Benign
0.62
D
LIST_S2
Benign
0.74
T
M_CAP
Benign
0.050
D
MetaRNN
Benign
0.23
T
MetaSVM
Uncertain
-0.14
T
MutationAssessor
Uncertain
2.0
M
PhyloP100
4.0
PrimateAI
Uncertain
0.52
T
PROVEAN
Benign
-0.78
N
REVEL
Uncertain
0.31
Sift
Benign
0.093
T
Sift4G
Benign
0.39
T
Polyphen
0.99
D
Vest4
0.20
MVP
0.84
MPC
0.46
ClinPred
0.065
T
GERP RS
5.3
Varity_R
0.13
gMVP
0.40
Mutation Taster
=82/18
polymorphism

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: rs761589948; hg19: chr17-62028813; COSMIC: COSV71126498; COSMIC: COSV71126498; API