rs773681556

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 5P and 5B. PM1PM5PP2BP6BS2

The NM_001165963.4(SCN1A):​c.2926A>C​(p.Met976Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000102 in 1,614,076 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. M976T) has been classified as Likely pathogenic.

Frequency

Genomes: š‘“ 0.000039 ( 0 hom., cov: 32)
Exomes š‘“: 0.00011 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

7
7
5

Clinical Significance

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

Conservation

PhyloP100: 8.01

Publications

1 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: Uncertain_significance. The variant received 0 ACMG points.

PM1
In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_001165963.4
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-166037795-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 373282.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
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.
BP6
Variant 2-166037796-T-G is Benign according to our data. Variant chr2-166037796-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 206792.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
BS2
High AC in GnomAd4 at 6 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN1ANM_001165963.4 linkc.2926A>C p.Met976Leu missense_variant Exon 18 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.2926A>C p.Met976Leu missense_variant Exon 18 of 29 NM_001165963.4 ENSP00000501589.1 P35498-1
SCN1AENST00000303395.9 linkc.2926A>C p.Met976Leu missense_variant Exon 17 of 28 5 ENSP00000303540.4 P35498-1
SCN1AENST00000375405.7 linkc.2893A>C p.Met965Leu missense_variant Exon 15 of 26 5 ENSP00000364554.3 P35498-2
SCN1AENST00000409050.2 linkc.2842A>C p.Met948Leu missense_variant Exon 17 of 28 5 ENSP00000386312.1 P35498-3

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152196
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000398
AC:
10
AN:
251466
AF XY:
0.0000294
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:
0.0000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000108
AC:
158
AN:
1461880
Hom.:
0
Cov.:
32
AF XY:
0.000102
AC XY:
74
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000131
AC:
146
AN:
1112000
Other (OTH)
AF:
0.000182
AC:
11
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
10
20
31
41
51
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:
0.0000394
AC:
6
AN:
152196
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74352
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41434
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
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:
0.0000882
AC:
6
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
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:
0.0000658
Hom.:
0
Bravo
AF:
0.0000529
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.000164
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

not provided Uncertain:2
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The SCN1A p.Met976Leu variant was not identified in the Cosmic, MutDB or LOVD 3.0 databases but was identified in dbSNP (ID: rs773681556) and ClinVar (reported as uncertain significance for neurodevelopement by Ambry Genetics). The variant was identified in control databases in 10 of 251466 chromosomes at a frequency of 0.00004 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following population: European (non-Finnish) in 10 of 113746 chromosomes (freq: 0.000088), but was not observed in the African, Latino, Ashkenazi Jewish, East Asian, European (Finnish), Other, and South Asian populations. Hildebrand et al. (2016) identified the p.Met976Leu variant in a patient with temporal lobe epilepsy, however this variant was suggested to be benign and was inherited from the patient's unaffected father, therefore not segregating with disease (Hildebrand_2016_PMID: 27029629). The p.Met976 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, and MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Jan 01, 2022
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Jul 19, 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
Nov 18, 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
Uncertain
0.45
BayesDel_addAF
Uncertain
0.10
D
BayesDel_noAF
Uncertain
0.11
CADD
Uncertain
25
DANN
Benign
0.95
DEOGEN2
Pathogenic
0.95
.;.;.;D;.;.;D;.;.;.
Eigen
Benign
0.13
Eigen_PC
Uncertain
0.30
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.89
D;D;D;D;.;D;.;.;D;D
M_CAP
Pathogenic
0.42
D
MetaRNN
Uncertain
0.62
D;D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.85
D
MutationAssessor
Benign
0.93
.;.;.;L;.;.;L;.;.;.
PhyloP100
8.0
PrimateAI
Pathogenic
0.81
D
PROVEAN
Uncertain
-2.9
.;.;.;D;.;.;D;.;D;D
REVEL
Pathogenic
0.73
Sift
Pathogenic
0.0
.;.;.;D;.;.;D;.;D;D
Sift4G
Benign
0.35
.;.;.;T;.;.;T;.;T;T
Polyphen
0.17, 0.12
.;.;.;B;B;.;B;B;B;.
Vest4
0.79, 0.85, 0.85, 0.82
MutPred
0.63
.;Gain of helix (P = 0.0325);.;Gain of helix (P = 0.0325);.;.;Gain of helix (P = 0.0325);.;.;.;
MVP
0.73
MPC
1.4
ClinPred
0.34
T
GERP RS
5.2
Varity_R
0.79
gMVP
0.88
Mutation Taster
=12/88
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: rs773681556; hg19: chr2-166894306; API