chr19-35034076-G-T

Position:

chr19-35034076-G-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The ENST00000415950.5(SCN1B):c.785G>T(p.Cys262Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000116 in 1,551,510 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C262Y) has been classified as Likely benign.

Frequency

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

Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

SCN1B
ENST00000415950.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.0200

Variant links:

Genes affected

SCN1B (HGNC:10586): (sodium voltage-gated channel beta subunit 1) Voltage-gated sodium channels are heteromeric proteins that function in the generation and propagation of action potentials in muscle and neuronal cells. They are composed of one alpha and two beta subunits, where the alpha subunit provides channel activity and the beta-1 subunit modulates the kinetics of channel inactivation. This gene encodes a sodium channel beta-1 subunit. Mutations in this gene result in generalized epilepsy with febrile seizures plus, Brugada syndrome 5, and defects in cardiac conduction. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2009]

SCN1B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.09809509).

BS2

High AC in GnomAdExome4 at 16 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
SCN1B	NM_001037.5 linkuse as main transcript	c.448+337G>T		intron_variant		ENST00000262631.11
SCN1B	NM_199037.5 linkuse as main transcript	c.785G>T	p.Cys262Phe	missense_variant	3/3
SCN1B	NM_001321605.2 linkuse as main transcript	c.349+337G>T		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN1B	ENST00000262631.11 linkuse as main transcript	c.448+337G>T		intron_variant		1	NM_001037.5	P1	Q07699-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152218

Hom.:

Cov.:

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000324

AC:

AN:

154118

Hom.:

AF XY:

0.0000368

AC XY:

AN XY:

81506

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000654

Gnomad NFE exome

AF:

0.0000670

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000114

AC:

AN:

1399292

Hom.:

Cov.:

AF XY:

0.0000159

AC XY:

AN XY:

690180

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.000101

Gnomad4 NFE exome

AF:

0.0000102

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74360

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000727

Hom.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Nov 03, 2023

Variant summary: SCN1B c.785G>T (p.Cys262Phe) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 154118 control chromosomes (gnomAD). 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.785G>T in individuals affected with SCN1B-Related Disorders and no experimental evidence demonstrating its impact on protein function have been reported. One submitter has cited a clinical-significance assessment for this variant to ClinVar after 2014 and has classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Brugada syndrome 5

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 30, 2023

ClinVar contains an entry for this variant (Variation ID: 933627). This variant has not been reported in the literature in individuals affected with SCN1B-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.01%). This sequence change replaces cysteine, which is neutral and slightly polar, with phenylalanine, which is neutral and non-polar, at codon 262 of the SCN1B protein (p.Cys262Phe). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.22

BayesDel_noAF

Benign

-0.37

CADD

Benign

3.0

DANN

Benign

0.97

Eigen

Benign

-1.1

Eigen_PC

Benign

-1.3

FATHMM_MKL

Benign

0.020

LIST_S2

Benign

0.27

T;T

M_CAP

Uncertain

0.15

MetaRNN

Benign

0.098

T;T

MetaSVM

Benign

-0.63

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.33

PROVEAN

Benign

-0.55

N;.

REVEL

Benign

0.097

Sift

Pathogenic

0.0

D;.

Polyphen

0.095

B;.

Vest4

0.13

MutPred

0.30

Loss of sheet (P = 0.007);.;

MVP

0.39

MPC

1.6

ClinPred

0.11

GERP RS

-0.38

gMVP

0.36

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