2-166012236-A-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM1PP2BS2

The NM_001165963.4(SCN1A):ā€‹c.3752T>Cā€‹(p.Met1251Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000621 in 1,609,902 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.000033 ( 0 hom., cov: 32)
Exomes š‘“: 0.0000034 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

7
9
3

Clinical Significance

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

Conservation

PhyloP100: 9.32
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM1
In a helix (size 31) in uniprot entity SCN1A_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_001165963.4
PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SCN1A. . Gene score misZ 5.2206 (greater than the threshold 3.09). Trascript score misZ 7.6022 (greater than threshold 3.09). GenCC has associacion of gene with migraine, familial hemiplegic, 3, familial hemiplegic migraine, Dravet syndrome, malignant migrating partial seizures of infancy, generalized epilepsy with febrile seizures plus, myoclonic-astatic epilepsy, developmental and epileptic encephalopathy, developmental and epileptic encephalopathy, 6, familial or sporadic hemiplegic migraine, arthrogryposis, Lennox-Gastaut syndrome, generalized epilepsy with febrile seizures plus, type 2.
BS2
High AC in GnomAd4 at 5 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
SCN1ANM_001165963.4 linkuse as main transcriptc.3752T>C p.Met1251Thr missense_variant 22/29 ENST00000674923.1 NP_001159435.1 P35498-1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SCN1AENST00000674923.1 linkuse as main transcriptc.3752T>C p.Met1251Thr missense_variant 22/29 NM_001165963.4 ENSP00000501589.1 P35498-1
SCN1AENST00000303395.9 linkuse as main transcriptc.3752T>C p.Met1251Thr missense_variant 21/285 ENSP00000303540.4 P35498-1
SCN1AENST00000375405.7 linkuse as main transcriptc.3719T>C p.Met1240Thr missense_variant 19/265 ENSP00000364554.3 P35498-2
SCN1AENST00000409050.1 linkuse as main transcriptc.3668T>C p.Met1223Thr missense_variant 19/265 ENSP00000386312.1 P35498-3

Frequencies

GnomAD3 genomes
AF:
0.0000264
AC:
4
AN:
151286
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000725
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000194
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000201
AC:
5
AN:
249350
Hom.:
0
AF XY:
0.0000148
AC XY:
2
AN XY:
134832
show subpopulations
Gnomad AFR exome
AF:
0.000186
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS 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:
0.00000343
AC:
5
AN:
1458498
Hom.:
0
Cov.:
30
AF XY:
0.00000276
AC XY:
2
AN XY:
725554
show subpopulations
Gnomad4 AFR exome
AF:
0.0000600
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000330
AC:
5
AN:
151404
Hom.:
0
Cov.:
32
AF XY:
0.0000270
AC XY:
2
AN XY:
73998
show subpopulations
Gnomad4 AFR
AF:
0.0000964
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000194
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000189
ExAC
AF:
0.0000330
AC:
4

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
Uncertain significance, criteria provided, single submitterclinical testingGeneDxDec 08, 2023In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Missense variants in this gene are a common cause of disease and they are underrepresented in the general population; This substitution is predicted to be within the transmembrane segment S2 of the third homologous domain; Has not been previously published as pathogenic or benign to our knowledge -
Uncertain significance, criteria provided, single submitterclinical testingInstitute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU DresdenNov 03, 2021- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpFeb 07, 2024Variant summary: SCN1A c.3752T>C (p.Met1251Thr) results in a non-conservative amino acid change located in the Ion transport domain (IPR005821) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 6.2e-06 in 1609902 control chromosomes, predominantly at a frequency of 8e-05 within the African or African-American subpopulation in the gnomAD database. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.3752T>C in individuals affected with SCN1A-Related Seizure Disorder and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 408940). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Early infantile epileptic encephalopathy with suppression bursts Benign:1
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 31, 2023- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.33
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Pathogenic
0.23
CADD
Uncertain
25
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.95
.;.;.;D;.;.;D;.;.;.
Eigen
Uncertain
0.34
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.89
D;D;D;D;.;D;.;.;D;D
M_CAP
Pathogenic
0.45
D
MetaRNN
Uncertain
0.74
D;D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Benign
0.79
.;.;.;N;.;.;N;.;.;.
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-3.3
.;.;.;D;.;.;D;.;D;D
REVEL
Pathogenic
0.80
Sift
Uncertain
0.0010
.;.;.;D;.;.;D;.;D;D
Sift4G
Uncertain
0.036
.;.;.;D;.;.;D;.;D;T
Polyphen
0.79, 0.97
.;.;.;P;D;.;P;D;D;.
Vest4
0.83, 0.84, 0.82
MutPred
0.60
.;Loss of stability (P = 0.0792);.;Loss of stability (P = 0.0792);.;.;Loss of stability (P = 0.0792);.;.;.;
MVP
0.90
MPC
0.99
ClinPred
0.75
D
GERP RS
5.5
Varity_R
0.65
gMVP
0.95

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.10
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs749638533; hg19: chr2-166868746; API