17-63938785-C-T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_000334.4(SCN4A):​c.*1986G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000525 in 152,248 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 (★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

SCN4A
NM_000334.4 3_prime_UTR

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.136

Publications

0 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 -4 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.81).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN4ANM_000334.4 linkc.*1986G>A 3_prime_UTR_variant Exon 24 of 24 ENST00000435607.3 NP_000325.4 P35499

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN4AENST00000435607.3 linkc.*1986G>A 3_prime_UTR_variant Exon 24 of 24 1 NM_000334.4 ENSP00000396320.1 P35499

Frequencies

GnomAD3 genomes
AF:
0.0000525
AC:
8
AN:
152248
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
530
Hom.:
0
Cov.:
0
AF XY:
0.00
AC XY:
0
AN XY:
324
African (AFR)
AF:
0.00
AC:
0
AN:
4
American (AMR)
AC:
0
AN:
0
Ashkenazi Jewish (ASJ)
AC:
0
AN:
0
East Asian (EAS)
AF:
0.00
AC:
0
AN:
2
South Asian (SAS)
AC:
0
AN:
0
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
426
Middle Eastern (MID)
AC:
0
AN:
0
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
92
Other (OTH)
AF:
0.00
AC:
0
AN:
6
GnomAD4 genome
AF:
0.0000525
AC:
8
AN:
152248
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74374
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.000378
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Congenital myopathy 22A, classic Uncertain:1
Nov 26, 2024
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

The heterozygous c.*1986G>A variant in SCN4A was identified by our study, in the compound heterozygous state, along with another variant of uncertain significance in one individual with congenital myopathy. Trio exome analysis revealed that this variant was in trans with the other variant. The c.*1986G>A variant in SCN4A has not been previously reported in the literature in individuals with congenital myopathy and has been identified in 0.01% (8/68138) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP rs1169978424). Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PM2_supporting (Richards 2015). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.81
CADD
Benign
4.0
DANN
Benign
0.38
PhyloP100
0.14

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: rs1169978424; hg19: chr17-62016145; API