rs183022730

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_020822.3(KCNT1):​c.279C>T​(p.Asn93Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000508 in 1,613,808 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000049 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: -0.829

Publications

4 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 -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.54).
BP6
Variant 9-135750122-C-T is Benign according to our data. Variant chr9-135750122-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 512972.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.829 with no splicing effect.
BS1
Variant frequency is greater than expected in population amr. GnomAdExome4 allele frequency = 0.0000493 (72/1461554) while in subpopulation AMR AF = 0.000738 (33/44712). AF 95% confidence interval is 0.00054. There are 0 homozygotes in GnomAdExome4. There are 39 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High AC in GnomAd4 at 10 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.279C>T p.Asn93Asn synonymous_variant Exon 3 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.279C>T p.Asn93Asn synonymous_variant Exon 3 of 31 1 NM_020822.3 ENSP00000360822.2 Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.0000592
AC:
9
AN:
152136
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000262
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000386
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:
0.0000997
AC:
25
AN:
250872
AF XY:
0.0000810
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000550
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.000490
GnomAD4 exome
AF:
0.0000493
AC:
72
AN:
1461554
Hom.:
0
Cov.:
31
AF XY:
0.0000536
AC XY:
39
AN XY:
727072
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.000738
AC:
33
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.000176
AC:
7
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53238
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000207
AC:
23
AN:
1111898
Other (OTH)
AF:
0.0000994
AC:
6
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.451
Heterozygous variant carriers
0
5
10
14
19
24
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:
0.0000657
AC:
10
AN:
152254
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74444
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41556
American (AMR)
AF:
0.000261
AC:
4
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000386
AC:
2
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68016
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000762
Hom.:
0
Bravo
AF:
0.0000793
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:1
Nov 02, 2017
GeneDx
Significance:Likely 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
Jan 23, 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 29, 2017
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, 14 Benign:1
Mar 15, 2022
Genome-Nilou Lab
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Mar 15, 2022
Genome-Nilou Lab
Significance:Likely 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
-0.54
CADD
Benign
11
DANN
Benign
0.71
PhyloP100
-0.83

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: rs183022730; hg19: chr9-138641968; COSMIC: COSV53699561; COSMIC: COSV53699561; API