12-51769230-C-A

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

6
7
6

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]

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
SCN8ANM_001330260.2 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 27 ENST00000627620.5 NP_001317189.1 Q9UQD0-2Q6B4S4
SCN8ANM_014191.4 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 27 ENST00000354534.11 NP_055006.1 Q9UQD0-1
SCN8ANM_001177984.3 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 26 NP_001171455.1 Q9UQD0-5
SCN8ANM_001369788.1 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 26 NP_001356717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN8AENST00000354534.11 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 27 1 NM_014191.4 ENSP00000346534.4 Q9UQD0-1
SCN8AENST00000627620.5 linkc.3267C>A p.Asn1089Lys missense_variant Exon 17 of 27 5 NM_001330260.2 ENSP00000487583.2 Q9UQD0-2
SCN8AENST00000599343.5 linkc.3300C>A p.Asn1100Lys missense_variant Exon 16 of 26 5 ENSP00000476447.3 Q9UQD0-3
SCN8AENST00000355133.7 linkc.3267C>A p.Asn1089Lys missense_variant Exon 16 of 25 1 ENSP00000347255.4 Q9UQD0-5

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000160
AC:
4
AN:
250118
Hom.:
0
AF XY:
0.0000222
AC XY:
3
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:
13
AN:
1461698
Hom.:
1
Cov.:
31
AF XY:
0.00000963
AC XY:
7
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.:
32
ExAC
AF:
0.0000165
AC:
2

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
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
16
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.83
D;.;.;.;.
Eigen
Benign
-0.15
Eigen_PC
Benign
-0.30
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.92
D;D;.;D;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.78
D;D;D;D;D
MetaSVM
Uncertain
0.44
D
MutationAssessor
Pathogenic
3.0
M;M;M;.;M
PrimateAI
Uncertain
0.78
T
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
D
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.

Other links and lift over

dbSNP: rs761386688; hg19: chr12-52163014; API