rs559344618

Variant summary

Our verdict is Benign. Variant got -16 ACMG points: 0P and 16B. BP6_Very_StrongBS1BS2

The NM_020822.3(KCNT1):​c.2236G>A​(p.Val746Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000706 in 1,488,298 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. V746V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000055 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

2
17

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: 2.45
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -16 ACMG points.

BP6
Variant 9-135772942-G-A is Benign according to our data. Variant chr9-135772942-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 386181.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000204 (31/152312) while in subpopulation AMR AF= 0.00183 (28/15306). AF 95% confidence interval is 0.0013. There are 0 homozygotes in gnomad4. There are 20 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
BS2
High AC in GnomAd4 at 31 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
KCNT1NM_020822.3 linkuse as main transcriptc.2236G>A p.Val746Met missense_variant 19/31 ENST00000371757.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
KCNT1ENST00000371757.7 linkuse as main transcriptc.2236G>A p.Val746Met missense_variant 19/311 NM_020822.3 A2Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.000204
AC:
31
AN:
152194
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00183
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:
0.00
GnomAD3 exomes
AF:
0.000221
AC:
22
AN:
99470
Hom.:
0
AF XY:
0.000209
AC XY:
11
AN XY:
52726
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00124
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000773
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000354
GnomAD4 exome
AF:
0.0000554
AC:
74
AN:
1335986
Hom.:
0
Cov.:
31
AF XY:
0.0000627
AC XY:
41
AN XY:
654028
show subpopulations
Gnomad4 AFR exome
AF:
0.0000668
Gnomad4 AMR exome
AF:
0.00172
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000142
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000200
Gnomad4 OTH exome
AF:
0.0000542
GnomAD4 genome
AF:
0.000204
AC:
31
AN:
152312
Hom.:
0
Cov.:
33
AF XY:
0.000269
AC XY:
20
AN XY:
74456
show subpopulations
Gnomad4 AFR
AF:
0.0000481
Gnomad4 AMR
AF:
0.00183
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.000170
ExAC
AF:
0.0000263
AC:
3
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Likely benign
Submissions summary: Benign:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Likely benign, criteria provided, single submitterclinical testingInvitaeJan 22, 2024- -
Inborn genetic diseases Benign:1
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsJan 29, 2018This 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. -
KCNT1-related disorder Benign:1
Likely benign, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesJul 06, 2021This 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). -
Developmental and epileptic encephalopathy, 14 Benign:1
Likely benign, criteria provided, single submitterclinical testingGenome-Nilou LabMar 15, 2022- -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxJun 28, 2021- -
Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Likely benign, criteria provided, single submitterclinical testingGenome-Nilou LabMar 15, 2022- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.069
BayesDel_addAF
Benign
-0.48
T
BayesDel_noAF
Benign
-0.49
CADD
Benign
19
DANN
Benign
0.82
DEOGEN2
Benign
0.036
.;.;.;.;.;.;.;.;T;.
Eigen
Benign
-0.95
Eigen_PC
Benign
-0.92
FATHMM_MKL
Benign
0.43
N
LIST_S2
Benign
0.82
T;T;T;T;T;T;T;T;T;T
M_CAP
Uncertain
0.11
D
MetaRNN
Benign
0.0069
T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.89
T
MutationAssessor
Benign
0.69
.;.;.;.;.;.;.;.;N;.
MutationTaster
Benign
1.0
N;N;N;N;N;N;N;N
PrimateAI
Uncertain
0.52
T
PROVEAN
Benign
-0.39
.;.;N;.;.;.;.;.;N;N
REVEL
Benign
0.12
Sift
Benign
0.14
.;.;T;.;.;.;.;.;T;T
Sift4G
Benign
0.27
T;T;T;T;T;T;T;T;T;T
Polyphen
0.0030
.;.;.;.;.;.;.;.;B;.
Vest4
0.25
MVP
0.52
MPC
0.80
ClinPred
0.019
T
GERP RS
0.89
Varity_R
0.033
gMVP
0.38

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.28
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.28
Position offset: 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: rs559344618; hg19: chr9-138664788; API