NM_001330260.2:c.1677C>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_ModerateBP6BP7BS1BS2

The NM_001330260.2(SCN8A):​c.1677C>T​(p.His559His) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000738 in 1,613,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00049 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000031 ( 0 hom. )

Consequence

SCN8A
NM_001330260.2 synonymous

Scores

2

Clinical Significance

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

Conservation

PhyloP100: 1.17

Publications

0 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.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.4).
BP6
Variant 12-51721587-C-T is Benign according to our data. Variant chr12-51721587-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 194087.
BP7
Synonymous conserved (PhyloP=1.17 with no splicing effect.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000486 (74/152336) while in subpopulation AFR AF = 0.00171 (71/41576). AF 95% confidence interval is 0.00139. There are 0 homozygotes in GnomAd4. There are 35 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High AC in GnomAd4 at 74 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN8ANM_001330260.2 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 27 ENST00000627620.5 NP_001317189.1 Q9UQD0-2Q6B4S4
SCN8ANM_014191.4 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 27 ENST00000354534.11 NP_055006.1 Q9UQD0-1
SCN8ANM_001177984.3 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 26 NP_001171455.1 Q9UQD0-5
SCN8ANM_001369788.1 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 26 NP_001356717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN8AENST00000354534.11 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 27 1 NM_014191.4 ENSP00000346534.4 Q9UQD0-1
SCN8AENST00000627620.5 linkc.1677C>T p.His559His synonymous_variant Exon 12 of 27 5 NM_001330260.2 ENSP00000487583.2 Q9UQD0-2
SCN8AENST00000599343.5 linkc.1677C>T p.His559His synonymous_variant Exon 11 of 26 5 ENSP00000476447.3 Q9UQD0-3
SCN8AENST00000355133.7 linkc.1677C>T p.His559His synonymous_variant Exon 11 of 25 1 ENSP00000347255.4 Q9UQD0-5

Frequencies

GnomAD3 genomes
AF:
0.000486
AC:
74
AN:
152218
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00171
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000147
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000102
AC:
25
AN:
246096
AF XY:
0.0000897
show subpopulations
Gnomad AFR exome
AF:
0.00167
Gnomad AMR exome
AF:
0.00
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:
0.00
GnomAD4 exome
AF:
0.0000308
AC:
45
AN:
1460664
Hom.:
0
Cov.:
31
AF XY:
0.0000317
AC XY:
23
AN XY:
726436
show subpopulations
African (AFR)
AF:
0.00126
AC:
42
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44622
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85950
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53332
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111418
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60324
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.000486
AC:
74
AN:
152336
Hom.:
0
Cov.:
31
AF XY:
0.000470
AC XY:
35
AN XY:
74498
show subpopulations
African (AFR)
AF:
0.00171
AC:
71
AN:
41576
American (AMR)
AF:
0.0000653
AC:
1
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68032
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
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:
0.000302
Hom.:
0
Bravo
AF:
0.000472
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:1
Jul 04, 2014
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 28, 2019
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Nov 01, 2018
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Developmental and epileptic encephalopathy Benign:1
Dec 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.40
CADD
Benign
12
DANN
Benign
0.95
PhyloP100
1.2

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs202212399; hg19: chr12-52115371; API