2-165991477-C-T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 3P and 7B. PM1PP2BP4_ModerateBP6BS2

The NM_001165963.4(SCN1A):​c.5798G>A​(p.Arg1933Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,613,658 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. R1933L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

7
12

Clinical Significance

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

Conservation

PhyloP100: 0.677

Publications

9 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: Likely_benign. The variant received -4 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 18 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=0.14824611).
BP6
Variant 2-165991477-C-T is Benign according to our data. Variant chr2-165991477-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1138334.
BS2
High AC in GnomAdExome4 at 19 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN1ANM_001165963.4 linkc.5798G>A p.Arg1933Gln missense_variant Exon 29 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.5798G>A p.Arg1933Gln missense_variant Exon 29 of 29 NM_001165963.4 ENSP00000501589.1 P35498-1
SCN1AENST00000303395.9 linkc.5798G>A p.Arg1933Gln missense_variant Exon 28 of 28 5 ENSP00000303540.4 P35498-1
SCN1AENST00000375405.7 linkc.5765G>A p.Arg1922Gln missense_variant Exon 26 of 26 5 ENSP00000364554.3 P35498-2
SCN1AENST00000409050.2 linkc.5714G>A p.Arg1905Gln missense_variant Exon 28 of 28 5 ENSP00000386312.1 P35498-3

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152016
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000798
AC:
2
AN:
250572
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000885
Gnomad OTH exome
AF:
0.000164
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461642
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
727122
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44682
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000162
AC:
18
AN:
1111856
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.522
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152016
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.00
AC:
0
AN:
15240
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Jun 28, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SCN1A c.5798G>A (p.Arg1933Gln) results in a conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 250572 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.5798G>A has been reported in the literature in an individual affected with SCN1A-Related Seizure Disorder (Turkyilmaz_2022). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One submitter has cited clinical-significance assessments for this variant to ClinVar after 2014 and has classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Developmental and epileptic encephalopathy Benign:1
Feb 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.071
BayesDel_addAF
Benign
-0.020
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
22
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.47
.;.;.;T;.;T;.;.;.
Eigen
Benign
-0.30
Eigen_PC
Benign
-0.044
FATHMM_MKL
Benign
0.72
D
LIST_S2
Uncertain
0.93
D;D;D;D;.;.;.;D;D
M_CAP
Uncertain
0.093
D
MetaRNN
Benign
0.15
T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.23
T
MutationAssessor
Uncertain
2.2
.;.;.;M;.;M;.;.;.
PhyloP100
0.68
PrimateAI
Benign
0.47
T
PROVEAN
Benign
-1.1
.;.;.;N;.;N;.;N;N
REVEL
Uncertain
0.31
Sift
Benign
0.76
.;.;.;T;.;T;.;T;T
Sift4G
Benign
0.43
.;.;.;T;.;T;.;T;T
Polyphen
0.0050
.;.;.;.;B;.;B;B;.
Vest4
0.090, 0.11, 0.099, 0.20
MutPred
0.54
.;.;.;Gain of helix (P = 0.0854);.;Gain of helix (P = 0.0854);.;.;.;
MVP
0.81
MPC
0.83
ClinPred
0.38
T
GERP RS
5.8
Varity_R
0.10
gMVP
0.64
Mutation Taster
=22/78
disease causing

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: rs556893466; hg19: chr2-166847987; COSMIC: COSV57662668; COSMIC: COSV57662668; API