rs367949317

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 1P and 13B. PP2BP4_StrongBP6BS1BS2

The NM_001330260.2(SCN8A):​c.1819G>A​(p.Ala607Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000105 in 1,596,556 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A607A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00057 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000056 ( 1 hom. )

Consequence

SCN8A
NM_001330260.2 missense

Scores

4
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:7

Conservation

PhyloP100: 3.64

Publications

4 publications found
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 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • developmental and epileptic encephalopathy, 13
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • cognitive impairment with or without cerebellar ataxia
    Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • seizures, benign familial infantile, 5
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • benign familial infantile epilepsy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • infantile convulsions and choreoathetosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • undetermined early-onset epileptic encephalopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myoclonus, familial, 2
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -12 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, developmental and epileptic encephalopathy, 13, undetermined early-onset epileptic encephalopathy, benign familial infantile epilepsy, complex neurodevelopmental disorder, seizures, benign familial infantile, 5, cognitive impairment with or without cerebellar ataxia, infantile convulsions and choreoathetosis.
BP4
Computational evidence support a benign effect (MetaRNN=0.01388976).
BP6
Variant 12-51721729-G-A is Benign according to our data. Variant chr12-51721729-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 194088.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000571 (87/152292) while in subpopulation AFR AF = 0.00176 (73/41574). AF 95% confidence interval is 0.00143. There are 0 homozygotes in GnomAd4. There are 46 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High AC in GnomAd4 at 87 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN8ANM_001330260.2 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 27 ENST00000627620.5 NP_001317189.1 Q9UQD0-2Q6B4S4
SCN8ANM_014191.4 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 27 ENST00000354534.11 NP_055006.1 Q9UQD0-1
SCN8ANM_001177984.3 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 26 NP_001171455.1 Q9UQD0-5
SCN8ANM_001369788.1 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 26 NP_001356717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN8AENST00000354534.11 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 27 1 NM_014191.4 ENSP00000346534.4 Q9UQD0-1
SCN8AENST00000627620.5 linkc.1819G>A p.Ala607Thr missense_variant Exon 12 of 27 5 NM_001330260.2 ENSP00000487583.2 Q9UQD0-2
SCN8AENST00000599343.5 linkc.1819G>A p.Ala607Thr missense_variant Exon 11 of 26 5 ENSP00000476447.3 Q9UQD0-3
SCN8AENST00000355133.7 linkc.1819G>A p.Ala607Thr missense_variant Exon 11 of 25 1 ENSP00000347255.4 Q9UQD0-5

Frequencies

GnomAD3 genomes
AF:
0.000572
AC:
87
AN:
152174
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00176
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000785
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:
0.000957
GnomAD2 exomes
AF:
0.000133
AC:
28
AN:
210124
AF XY:
0.0000870
show subpopulations
Gnomad AFR exome
AF:
0.00189
Gnomad AMR exome
AF:
0.000168
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000189
GnomAD4 exome
AF:
0.0000561
AC:
81
AN:
1444264
Hom.:
1
Cov.:
31
AF XY:
0.0000474
AC XY:
34
AN XY:
717090
show subpopulations
African (AFR)
AF:
0.00181
AC:
60
AN:
33126
American (AMR)
AF:
0.000147
AC:
6
AN:
40872
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25742
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38778
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84560
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51968
Middle Eastern (MID)
AF:
0.000348
AC:
2
AN:
5740
European-Non Finnish (NFE)
AF:
0.00000181
AC:
2
AN:
1103752
Other (OTH)
AF:
0.000184
AC:
11
AN:
59726
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
Heterozygous variant carriers
0
5
11
16
22
27
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000571
AC:
87
AN:
152292
Hom.:
0
Cov.:
31
AF XY:
0.000618
AC XY:
46
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.00176
AC:
73
AN:
41574
American (AMR)
AF:
0.000784
AC:
12
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68004
Other (OTH)
AF:
0.000947
AC:
2
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000133
Hom.:
0
Bravo
AF:
0.000529
ESP6500AA
AF:
0.000508
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000176
AC:
21
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:7
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:4
Jun 08, 2018
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 30, 2019
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

SCN8A: BS1 -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Nov 27, 2018
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Developmental and epileptic encephalopathy Benign:1
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SCN8A-related disorder Benign:1
Jan 18, 2021
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.085
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.25
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Benign
0.35
.;T;.;.;.;.;.
Eigen
Benign
-0.22
Eigen_PC
Benign
-0.089
FATHMM_MKL
Benign
0.65
D
LIST_S2
Uncertain
0.90
D;D;D;.;D;D;D
M_CAP
Benign
0.084
D
MetaRNN
Benign
0.014
T;T;T;T;T;T;T
MetaSVM
Uncertain
0.090
D
MutationAssessor
Benign
0.34
.;N;N;N;N;N;.
PhyloP100
3.6
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
-0.20
.;N;N;N;.;.;.
REVEL
Benign
0.20
Sift
Benign
0.36
.;T;T;T;.;.;.
Sift4G
Benign
0.40
.;T;T;T;T;T;T
Polyphen
0.0020, 0.017
.;B;.;.;B;.;.
Vest4
0.27, 0.27, 0.34, 0.38, 0.28
MVP
0.67
MPC
1.0
ClinPred
0.021
T
GERP RS
3.8
Varity_R
0.14
gMVP
0.55
Mutation Taster
=93/7
polymorphism

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

Other links and lift over

dbSNP: rs367949317; hg19: chr12-52115513; API