NM_001330260.2:c.3267C>A

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PP2PP3BS2

The NM_001330260.2(SCN8A):c.3267C>A(p.Asn1089Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000889 in 1,461,698 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000089 ( 1 hom. )

Consequence

SCN8A
NM_001330260.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 0.556

Variant links:

Genes affected

SCN8A (HGNC:10596): (sodium voltage-gated channel alpha subunit 8) This gene encodes a member of the sodium channel alpha subunit gene family. The encoded protein forms the ion pore region of the voltage-gated sodium channel. This protein is essential for the rapid membrane depolarization that occurs during the formation of the action potential in excitable neurons. Mutations in this gene are associated with cognitive disability, pancerebellar atrophy and ataxia. Alternate splicing results in multiple transcript variants.[provided by RefSeq, May 2010]

SCN8A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PP2

Missense variant in the SCN8A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 213 curated pathogenic missense variants (we use a threshold of 10). The gene has 45 curated benign missense variants. Gene score misZ: 0.78755 (below the threshold of 3.09). Trascript score misZ: 10.436 (above the threshold of 3.09). GenCC associations: The gene is linked to myoclonus, familial, 2, infantile convulsions and choreoathetosis, cognitive impairment with or without cerebellar ataxia, undetermined early-onset epileptic encephalopathy, complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 13, benign familial infantile epilepsy, seizures, benign familial infantile, 5.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.779

BS2

High AC in GnomAdExome4 at 13 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN8A	NM_001330260.2 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 27	ENST00000627620.5	NP_001317189.1	Q9UQD0-2Q6B4S4
SCN8A	NM_014191.4 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 27	ENST00000354534.11	NP_055006.1	Q9UQD0-1
SCN8A	NM_001177984.3 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 26		NP_001171455.1	Q9UQD0-5
SCN8A	NM_001369788.1 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 26		NP_001356717.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
SCN8A	ENST00000354534.11 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 27	1	NM_014191.4	ENSP00000346534.4	Q9UQD0-1
SCN8A	ENST00000627620.5 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 17 of 27	5	NM_001330260.2	ENSP00000487583.2	Q9UQD0-2
SCN8A	ENST00000599343.5 link	c.3300C>A	p.Asn1100Lys	missense_variant	Exon 16 of 26	5		ENSP00000476447.3	Q9UQD0-3
SCN8A	ENST00000355133.7 link	c.3267C>A	p.Asn1089Lys	missense_variant	Exon 16 of 25	1		ENSP00000347255.4	Q9UQD0-5

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000160

AC:

AN:

250118

Hom.:

AF XY:

0.0000222

AC XY:

AN XY:

135318

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:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000177

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.00000889

AC:

AN:

1461698

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727130

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:

0.0000580

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000630

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 13

Pathogenic:1

Dec 03, 2017

Genomic Research Center, Shahid Beheshti University of Medical Sciences

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Early infantile epileptic encephalopathy with suppression bursts

Uncertain:1

Dec 27, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 522699). 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) performed at Invitae indicates that this missense variant is not expected to disrupt SCN8A protein function. 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. This variant has not been reported in the literature in individuals affected with SCN8A-related conditions. This sequence change replaces asparagine, which is neutral and polar, with lysine, which is basic and polar, at codon 1089 of the SCN8A protein (p.Asn1089Lys). This variant is present in population databases (rs761386688, gnomAD 0.003%). -

See cases

Uncertain:1

Apr 18, 2023

Institute of Human Genetics, University Hospital Muenster

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ACMG categories: PM2 -

not provided

Uncertain:1

Jun 01, 2019

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.97

BayesDel_addAF

Benign

-0.030

BayesDel_noAF

Benign

-0.18

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.83

D;.;.;.;.

Eigen

Benign

-0.15

Eigen_PC

Benign

-0.30

FATHMM_MKL

Uncertain

0.93

LIST_S2

Uncertain

0.92

D;D;.;D;D

M_CAP

Pathogenic

0.41

MetaRNN

Pathogenic

0.78

D;D;D;D;D

MetaSVM

Uncertain

0.44

MutationAssessor

Pathogenic

3.0

M;M;M;.;M

PrimateAI

Uncertain

0.78

PROVEAN

Pathogenic

-5.4

D;D;D;.;.

REVEL

Uncertain

0.56

Sift

Uncertain

0.0010

D;D;D;.;.

Sift4G

Benign

0.096

T;T;T;T;T

Polyphen

0.99

D;.;.;.;.

Vest4

0.81

MutPred

0.60

Gain of methylation at N1089 (P = 0.0085);Gain of methylation at N1089 (P = 0.0085);Gain of methylation at N1089 (P = 0.0085);.;Gain of methylation at N1089 (P = 0.0085);

MVP

0.85

MPC

2.0

ClinPred

0.97

GERP RS

-4.1

Varity_R

0.90

gMVP

0.84

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