rs201156458

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_020822.3(KCNT1):​c.3256G>A​(p.Gly1086Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000249 in 1,609,646 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0011 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00016 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

4
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: 1.97

Publications

3 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 -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0073287487).
BP6
Variant 9-135786275-G-A is Benign according to our data. Variant chr9-135786275-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 380825.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.0011 (167/152226) while in subpopulation AFR AF = 0.00356 (148/41552). AF 95% confidence interval is 0.00309. There are 0 homozygotes in GnomAd4. There are 84 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High AC in GnomAd4 at 167 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.3256G>A p.Gly1086Arg missense_variant Exon 29 of 31 ENST00000371757.7 NP_065873.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNT1ENST00000371757.7 linkc.3256G>A p.Gly1086Arg missense_variant Exon 29 of 31 1 NM_020822.3 ENSP00000360822.2

Frequencies

GnomAD3 genomes
AF:
0.00110
AC:
168
AN:
152110
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00360
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000720
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.000188
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00143
GnomAD2 exomes
AF:
0.000267
AC:
61
AN:
228620
AF XY:
0.000213
show subpopulations
Gnomad AFR exome
AF:
0.00340
Gnomad AMR exome
AF:
0.000148
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000146
Gnomad NFE exome
AF:
0.0000805
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000160
AC:
233
AN:
1457420
Hom.:
0
Cov.:
36
AF XY:
0.000152
AC XY:
110
AN XY:
724828
show subpopulations
African (AFR)
AF:
0.00419
AC:
140
AN:
33440
American (AMR)
AF:
0.000180
AC:
8
AN:
44530
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26024
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39580
South Asian (SAS)
AF:
0.000105
AC:
9
AN:
85786
European-Finnish (FIN)
AF:
0.0000779
AC:
4
AN:
51328
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5734
European-Non Finnish (NFE)
AF:
0.0000468
AC:
52
AN:
1110876
Other (OTH)
AF:
0.000316
AC:
19
AN:
60122
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
15
30
45
60
75
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.00110
AC:
167
AN:
152226
Hom.:
0
Cov.:
33
AF XY:
0.00113
AC XY:
84
AN XY:
74450
show subpopulations
African (AFR)
AF:
0.00356
AC:
148
AN:
41552
American (AMR)
AF:
0.000719
AC:
11
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5154
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4824
European-Finnish (FIN)
AF:
0.000188
AC:
2
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67978
Other (OTH)
AF:
0.00142
AC:
3
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
9
18
26
35
44
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000452
Hom.:
0
Bravo
AF:
0.00125
ESP6500AA
AF:
0.00249
AC:
10
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000280
AC:
33

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:1
Jan 26, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

KCNT1: BP4, BS1 -

not specified Benign:1
Jul 19, 2016
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Jun 28, 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
0.12
BayesDel_addAF
Benign
-0.40
T
BayesDel_noAF
Benign
-0.35
CADD
Benign
15
DANN
Uncertain
0.97
DEOGEN2
Benign
0.023
.;.;.;.;.;.;.;.;T;.
Eigen
Benign
-0.37
Eigen_PC
Benign
-0.45
FATHMM_MKL
Benign
0.67
D
LIST_S2
Uncertain
0.88
D;D;D;D;D;D;D;D;D;D
M_CAP
Uncertain
0.092
D
MetaRNN
Benign
0.0073
T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.5
.;.;.;.;.;.;.;.;L;.
PhyloP100
2.0
PrimateAI
Uncertain
0.49
T
PROVEAN
Benign
0.0
.;.;N;.;.;.;.;.;.;N
REVEL
Benign
0.050
Sift
Benign
0.29
.;.;T;.;.;.;.;.;.;T
Sift4G
Benign
0.23
T;T;T;T;T;T;T;T;T;T
Vest4
0.46
MVP
0.47
MPC
0.11
ClinPred
0.091
T
GERP RS
4.1
Varity_R
0.14
gMVP
0.25
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs201156458; hg19: chr9-138678121; API