rs121917910

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 3P and 13B. PM1PP2BP4_StrongBP6BS1BS2

The NM_001165963.4(SCN1A):​c.3924A>T​(p.Glu1308Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000852 in 1,607,484 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1308K) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00064 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00087 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

2
7
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:11O:1

Conservation

PhyloP100: 1.27

Publications

14 publications found
Variant links:
Genes affected
SCN1A (HGNC:10585): (sodium voltage-gated channel alpha subunit 1) Voltage-dependent sodium channels are heteromeric complexes that regulate sodium exchange between intracellular and extracellular spaces and are essential for the generation and propagation of action potentials in muscle cells and neurons. Each sodium channel is composed of a large pore-forming, glycosylated alpha subunit and two smaller beta subunits. This gene encodes a sodium channel alpha subunit, which has four homologous domains, each of which contains six transmembrane regions. Allelic variants of this gene are associated with generalized epilepsy with febrile seizures and epileptic encephalopathy. Alternative splicing results in multiple transcript variants. The RefSeq Project has decided to create four representative RefSeq records. Three of the transcript variants are supported by experimental evidence and the fourth contains alternate 5' untranslated exons, the exact combination of which have not been experimentally confirmed for the full-length transcript. [provided by RefSeq, Oct 2015]
SCN1A-AS1 (HGNC:54069): (SCN1A and SCN9A antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -10 ACMG points.

PM1
In a hotspot region, there are 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 6 uncertain in NM_001165963.4
PP2
Missense variant in the SCN1A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 848 curated pathogenic missense variants (we use a threshold of 10). The gene has 89 curated benign missense variants. Gene score misZ: 5.2206 (above the threshold of 3.09). Trascript score misZ: 7.6022 (above the threshold of 3.09). GenCC associations: The gene is linked to familial or sporadic hemiplegic migraine, myoclonic-astatic epilepsy, arthrogryposis, Dravet syndrome, malignant migrating partial seizures of infancy, generalized epilepsy with febrile seizures plus, type 2, migraine, familial hemiplegic, 3, developmental and epileptic encephalopathy, 6A, familial hemiplegic migraine, generalized epilepsy with febrile seizures plus, genetic developmental and epileptic encephalopathy, Lennox-Gastaut syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.057480246).
BP6
Variant 2-166009797-T-A is Benign according to our data. Variant chr2-166009797-T-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 68534.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000642 (97/151094) while in subpopulation NFE AF = 0.00116 (78/67298). AF 95% confidence interval is 0.000952. There are 0 homozygotes in GnomAd4. There are 39 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 97 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN1ANM_001165963.4 linkc.3924A>T p.Glu1308Asp missense_variant Exon 23 of 29 ENST00000674923.1 NP_001159435.1 P35498-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN1AENST00000674923.1 linkc.3924A>T p.Glu1308Asp missense_variant Exon 23 of 29 NM_001165963.4 ENSP00000501589.1 P35498-1
SCN1AENST00000303395.9 linkc.3924A>T p.Glu1308Asp missense_variant Exon 22 of 28 5 ENSP00000303540.4 P35498-1
SCN1AENST00000375405.7 linkc.3891A>T p.Glu1297Asp missense_variant Exon 20 of 26 5 ENSP00000364554.3 P35498-2
SCN1AENST00000409050.2 linkc.3840A>T p.Glu1280Asp missense_variant Exon 22 of 28 5 ENSP00000386312.1 P35498-3

Frequencies

GnomAD3 genomes
AF:
0.000642
AC:
97
AN:
150976
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000218
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000265
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000472
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00116
Gnomad OTH
AF:
0.000483
GnomAD2 exomes
AF:
0.000607
AC:
152
AN:
250236
AF XY:
0.000673
show subpopulations
Gnomad AFR exome
AF:
0.000309
Gnomad AMR exome
AF:
0.0000872
Gnomad ASJ exome
AF:
0.000199
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000509
Gnomad NFE exome
AF:
0.00114
Gnomad OTH exome
AF:
0.000328
GnomAD4 exome
AF:
0.000873
AC:
1272
AN:
1456390
Hom.:
0
Cov.:
30
AF XY:
0.000867
AC XY:
628
AN XY:
724606
show subpopulations
African (AFR)
AF:
0.0000602
AC:
2
AN:
33224
American (AMR)
AF:
0.000180
AC:
8
AN:
44506
Ashkenazi Jewish (ASJ)
AF:
0.000116
AC:
3
AN:
25906
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39480
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86122
European-Finnish (FIN)
AF:
0.000787
AC:
42
AN:
53364
Middle Eastern (MID)
AF:
0.000349
AC:
2
AN:
5724
European-Non Finnish (NFE)
AF:
0.00105
AC:
1168
AN:
1108034
Other (OTH)
AF:
0.000766
AC:
46
AN:
60030
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
56
112
169
225
281
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
42
84
126
168
210
<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:
0.000642
AC:
97
AN:
151094
Hom.:
0
Cov.:
32
AF XY:
0.000528
AC XY:
39
AN XY:
73854
show subpopulations
African (AFR)
AF:
0.000217
AC:
9
AN:
41390
American (AMR)
AF:
0.000265
AC:
4
AN:
15108
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3440
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5134
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.000472
AC:
5
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00116
AC:
78
AN:
67298
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
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
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:
0.000952
Hom.:
0
Bravo
AF:
0.000536
TwinsUK
AF:
0.000539
AC:
2
ALSPAC
AF:
0.00104
AC:
4
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000930
AC:
8
ExAC
AF:
0.000750
AC:
91
EpiCase
AF:
0.000820
EpiControl
AF:
0.00125

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:11Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:5
Jun 03, 2019
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 20729507, 18930999, 19522081, 28717674, 27881154, 26990884, 31765958, 32090326) -

Apr 03, 2014
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

SCN1A: PP3, BS1, BS2 -

not specified Benign:2
Jul 03, 2019
Genetic Services Laboratory, University of Chicago
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 31, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Severe myoclonic epilepsy in infancy Benign:1Other:1
-
UniProtKB/Swiss-Prot
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Aug 22, 2023
Mendelics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Migraine, familial hemiplegic, 3 Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Generalized epilepsy with febrile seizures plus, type 2 Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Inborn genetic diseases Benign:1
Aug 14, 2018
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Developmental and epileptic encephalopathy Benign:1
Jan 28, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SCN1A-related disorder Benign:1
Dec 19, 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). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Benign
-0.058
T
BayesDel_noAF
Uncertain
0.10
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.84
.;.;.;D;.;.;D;.;.;.
Eigen
Benign
-0.13
Eigen_PC
Benign
0.066
FATHMM_MKL
Uncertain
0.84
D
LIST_S2
Uncertain
0.87
D;D;D;D;.;D;.;.;D;D
M_CAP
Uncertain
0.11
D
MetaRNN
Benign
0.057
T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.70
D
MutationAssessor
Benign
0.050
.;.;.;N;.;.;N;.;.;.
PhyloP100
1.3
PrimateAI
Pathogenic
0.89
D
PROVEAN
Benign
-1.3
.;.;.;N;.;.;N;.;N;N
REVEL
Uncertain
0.50
Sift
Benign
0.28
.;.;.;T;.;.;T;.;T;T
Sift4G
Benign
0.68
.;.;.;T;.;.;T;.;T;T
Polyphen
0.047, 0.96
.;.;.;B;D;.;B;D;D;.
Vest4
0.44, 0.43, 0.46, 0.40
MutPred
0.47
.;Loss of loop (P = 0.0804);.;Loss of loop (P = 0.0804);.;.;Loss of loop (P = 0.0804);.;.;.;
MVP
0.95
MPC
0.71
ClinPred
0.060
T
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.22
gMVP
0.88
Mutation Taster
=0/100
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs121917910; hg19: chr2-166866307; API