chr2-166039490-G-A

Position:

chr2-166039490-G-A

Variant summary

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

The NM_001165963.4(SCN1A):c.2522C>T(p.Thr841Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000223 in 1,612,766 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: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.29

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 links:

SCN1A-AS1 (HGNC:54069): (SCN1A and SCN9A antisense RNA 1)

SCN1A-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM1

In a repeat II (size 272) in uniprot entity SCN1A_HUMAN there are 49 pathogenic changes around while only 2 benign (96%) 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 GnomAdExome4 at 34 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN1A	NM_001165963.4 linkuse as main transcript	c.2522C>T	p.Thr841Met	missense_variant	17/29	ENST00000674923.1	NP_001159435.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN1A	ENST00000674923.1 linkuse as main transcript	c.2522C>T	p.Thr841Met	missense_variant	17/29		NM_001165963.4	ENSP00000501589	P4	P35498-1
SCN1A-AS1	ENST00000651574.1 linkuse as main transcript	n.487+3360G>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151074

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000488

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000318

AC:

AN:

251260

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135798

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

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:

0.0000264

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000233

AC:

AN:

1461692

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

727136

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000894

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:

0.0000252

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151074

Hom.:

Cov.:

AF XY:

0.0000136

AC XY:

AN XY:

73656

show subpopulations

Gnomad4 AFR

AF:

0.0000488

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000868

Hom.:

Bravo

AF:

0.0000378

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:1Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Severe myoclonic epilepsy in infancy

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory of Medical Genetics, National & Kapodistrian University of Athens

Aug 10, 2021

PM1, PM5, PP2, PP3 -

Early infantile epileptic encephalopathy with suppression bursts

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 16, 2023

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on SCN1A protein function. ClinVar contains an entry for this variant (Variation ID: 851254). This variant has not been reported in the literature in individuals affected with SCN1A-related conditions. This variant is present in population databases (rs750901301, gnomAD 0.01%). This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 841 of the SCN1A protein (p.Thr841Met). -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 02, 2021

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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.23

BayesDel_addAF

Uncertain

0.12

BayesDel_noAF

Pathogenic

0.16

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.88

.;.;.;D;.;.;D;.;.;.

Eigen

Uncertain

0.25

Eigen_PC

Uncertain

0.31

FATHMM_MKL

Uncertain

0.91

LIST_S2

Uncertain

0.89

D;D;D;D;.;D;.;.;D;D

M_CAP

Pathogenic

0.61

MetaRNN

Uncertain

0.53

D;D;D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Benign

1.3

.;.;.;L;.;.;L;.;.;.

MutationTaster

Benign

0.92

D;D;D;D

PrimateAI

Pathogenic

0.80

PROVEAN

Benign

-2.4

.;.;.;N;.;.;N;.;N;N

REVEL

Pathogenic

0.69

Sift

Uncertain

0.0030

.;.;.;D;.;.;D;.;D;D

Sift4G

Benign

0.15

.;.;.;T;.;.;T;.;T;T

Polyphen

0.023, 0.99

.;.;.;B;D;.;B;D;D;.

Vest4

0.76, 0.74, 0.77, 0.73

MutPred

0.49

.;Loss of helix (P = 0.2022);.;Loss of helix (P = 0.2022);.;.;Loss of helix (P = 0.2022);.;.;.;

MVP

0.96

MPC

2.6

ClinPred

0.26

GERP RS

4.7

Varity_R

0.25

gMVP

0.96

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over