rs376758763

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_020822.3(KCNT1):​c.2527G>A​(p.Asp843Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000941 in 1,550,890 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D843Y) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000093 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

1
7
11

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 9.65

Publications

2 publications found
Variant links:
Genes affected
KCNT1 (HGNC:18865): (potassium sodium-activated channel subfamily T member 1) Potassium channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a sodium-activated potassium channel subunit which is thought to function in ion conductance and developmental signaling pathways. Mutations in this gene cause the early-onset epileptic disorders, malignant migrating partial seizures of infancy and autosomal dominant nocturnal frontal lobe epilepsy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2012]
KCNT1 Gene-Disease associations (from GenCC):
  • childhood-onset epilepsy syndrome
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • developmental and epileptic encephalopathy, 14
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
  • malignant migrating partial seizures of infancy
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
  • autosomal dominant nocturnal frontal lobe epilepsy 5
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • autosomal dominant nocturnal frontal lobe epilepsy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.201121).
BP6
Variant 9-135778428-G-A is Benign according to our data. Variant chr9-135778428-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 833602.
BS2
High AC in GnomAd4 at 16 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.2527G>A p.Asp843Asn missense_variant Exon 22 of 31 ENST00000371757.7 NP_065873.2 Q5JUK3-3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNT1ENST00000371757.7 linkc.2527G>A p.Asp843Asn missense_variant Exon 22 of 31 1 NM_020822.3 ENSP00000360822.2 Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.000105
AC:
16
AN:
152178
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000565
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000897
AC:
14
AN:
156076
AF XY:
0.0000609
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000404
Gnomad ASJ exome
AF:
0.000117
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000401
Gnomad NFE exome
AF:
0.0000827
Gnomad OTH exome
AF:
0.000226
GnomAD4 exome
AF:
0.0000929
AC:
130
AN:
1398712
Hom.:
0
Cov.:
32
AF XY:
0.0000884
AC XY:
61
AN XY:
689878
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31594
American (AMR)
AF:
0.0000280
AC:
1
AN:
35712
Ashkenazi Jewish (ASJ)
AF:
0.0000397
AC:
1
AN:
25176
East Asian (EAS)
AF:
0.0000280
AC:
1
AN:
35746
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79246
European-Finnish (FIN)
AF:
0.000577
AC:
28
AN:
48564
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5668
European-Non Finnish (NFE)
AF:
0.0000843
AC:
91
AN:
1079006
Other (OTH)
AF:
0.000138
AC:
8
AN:
58000
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
6
13
19
26
32
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
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:
0.000105
AC:
16
AN:
152178
Hom.:
0
Cov.:
33
AF XY:
0.000148
AC XY:
11
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.000565
AC:
6
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.516
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000409
Hom.:
0
Bravo
AF:
0.0000567
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000123
AC:
1
ExAC
AF:
0.0000561
AC:
5

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1
Mar 19, 2020
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Jan 16, 2024
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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.27
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.26
.;.;.;.;.;.;.;.;T;.
Eigen
Benign
0.12
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.97
D;D;D;D;D;D;D;D;D;D
M_CAP
Uncertain
0.095
D
MetaRNN
Benign
0.20
T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.46
T
MutationAssessor
Benign
1.4
.;.;.;.;.;.;.;.;L;.
PhyloP100
9.7
PrimateAI
Uncertain
0.55
T
PROVEAN
Uncertain
-2.6
.;.;D;.;.;.;.;.;N;N
REVEL
Uncertain
0.36
Sift
Benign
0.29
.;.;T;.;.;.;.;.;T;T
Sift4G
Benign
0.29
T;T;T;T;T;T;T;T;T;T
Polyphen
0.17
.;.;.;.;.;.;.;.;B;.
Vest4
0.42
MVP
0.82
MPC
0.64
ClinPred
0.19
T
GERP RS
4.7
Varity_R
0.29
gMVP
0.65
Mutation Taster
=49/51
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs376758763; hg19: chr9-138670274; COSMIC: COSV53713445; API