rs768638174

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 3P and 6B. PM1PP2BP4BP6BS2

The NM_001165963.4(SCN1A):​c.4345C>T​(p.Leu1449Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000262 in 1,602,804 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).

Frequency

Genomes: 𝑓 0.000040 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

1
6
12

Clinical Significance

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

Conservation

PhyloP100: 1.44

Publications

0 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 -3 ACMG points.

PM1
In a hotspot region, there are 17 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 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=0.29965836).
BP6
Variant 2-165998169-G-A is Benign according to our data. Variant chr2-165998169-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 206826.
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.4345C>T p.Leu1449Phe missense_variant Exon 26 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.4345C>T p.Leu1449Phe missense_variant Exon 26 of 29 NM_001165963.4 ENSP00000501589.1 P35498-1
SCN1AENST00000303395.9 linkc.4345C>T p.Leu1449Phe missense_variant Exon 25 of 28 5 ENSP00000303540.4 P35498-1
SCN1AENST00000375405.7 linkc.4312C>T p.Leu1438Phe missense_variant Exon 23 of 26 5 ENSP00000364554.3 P35498-2
SCN1AENST00000409050.2 linkc.4261C>T p.Leu1421Phe missense_variant Exon 25 of 28 5 ENSP00000386312.1 P35498-3

Frequencies

GnomAD3 genomes
AF:
0.0000397
AC:
6
AN:
151068
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000742
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000804
AC:
2
AN:
248670
AF XY:
0.00
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:
0.0000178
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000248
AC:
36
AN:
1451736
Hom.:
0
Cov.:
29
AF XY:
0.0000291
AC XY:
21
AN XY:
722342
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33080
American (AMR)
AF:
0.00
AC:
0
AN:
44390
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25776
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39360
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85268
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53198
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5650
European-Non Finnish (NFE)
AF:
0.0000317
AC:
35
AN:
1105176
Other (OTH)
AF:
0.00
AC:
0
AN:
59838
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.411
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.0000397
AC:
6
AN:
151068
Hom.:
0
Cov.:
32
AF XY:
0.0000136
AC XY:
1
AN XY:
73740
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41302
American (AMR)
AF:
0.00
AC:
0
AN:
15112
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3450
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5140
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10564
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000742
AC:
5
AN:
67370
Other (OTH)
AF:
0.00
AC:
0
AN:
2072
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000671
Hom.:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

not provided Uncertain:2
Oct 01, 2019
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 23, 2014
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The L1449F variant has not been published as a mutation, nor has it been reported as a benign polymorphism to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This substitution alters a conserved position between transmembrane segments 5 and 6 in the third homologous domain. Multiple missense mutations in nearby residues have been reported in association with SCN1A-related disorders, supporting the functional importance of this region of the protein. However, the L1449F variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties, and in silico analysis predicts this variant likely does not alter the protein structure/function. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic mutation or a rare benign variant. The variant is found in EPILEPSY,CHILD-EPI panel(s). -

not specified Uncertain:1
Aug 18, 2016
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Developmental and epileptic encephalopathy Benign:1
Dec 25, 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
0.23
BayesDel_addAF
Uncertain
0.026
T
BayesDel_noAF
Benign
-0.14
CADD
Benign
20
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.78
.;.;.;D;.;.;D;.;.;.
Eigen
Benign
-0.096
Eigen_PC
Benign
-0.11
FATHMM_MKL
Benign
0.41
N
LIST_S2
Benign
0.68
T;T;T;T;.;T;.;.;T;T
M_CAP
Pathogenic
0.33
D
MetaRNN
Benign
0.30
T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.70
D
MutationAssessor
Benign
1.4
.;.;.;L;.;.;L;.;.;.
PhyloP100
1.4
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-1.0
.;.;.;N;.;.;N;.;N;N
REVEL
Uncertain
0.45
Sift
Benign
0.059
.;.;.;T;.;.;T;.;T;T
Sift4G
Uncertain
0.038
.;.;.;D;.;.;D;.;D;D
Polyphen
0.55, 0.44
.;.;.;P;B;.;P;B;B;.
Vest4
0.47, 0.48, 0.46, 0.46
MVP
0.54
MPC
0.79
ClinPred
0.38
T
GERP RS
3.5
Varity_R
0.078
gMVP
0.92
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: rs768638174; hg19: chr2-166854679; API