chr9-135765033-C-T

Variant summary

Our verdict is Benign. The variant received -15 ACMG points: 0P and 15B. BP4_ModerateBP6_Very_StrongBP7BS2

The NM_020822.3(KCNT1):​c.1038C>T​(p.Phe346Phe) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000268 in 1,605,156 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 splice_region, synonymous

Scores

2

Clinical Significance

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

Conservation

PhyloP100: -0.872

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 -15 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.43).
BP6
Variant 9-135765033-C-T is Benign according to our data. Variant chr9-135765033-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 473354.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.872 with no splicing effect.
BS2
High AC in GnomAdExome4 at 40 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.1038C>T p.Phe346Phe splice_region_variant, synonymous_variant Exon 12 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.1038C>T p.Phe346Phe splice_region_variant, synonymous_variant Exon 12 of 31 1 NM_020822.3 ENSP00000360822.2 Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152202
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000322
AC:
8
AN:
248622
AF XY:
0.0000445
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000546
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000268
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000275
AC:
40
AN:
1452954
Hom.:
0
Cov.:
33
AF XY:
0.0000333
AC XY:
24
AN XY:
721048
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33310
American (AMR)
AF:
0.0000898
AC:
4
AN:
44522
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26066
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39492
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86100
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52438
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5744
European-Non Finnish (NFE)
AF:
0.0000299
AC:
33
AN:
1105332
Other (OTH)
AF:
0.0000334
AC:
2
AN:
59950
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.0000197
AC:
3
AN:
152202
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41434
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000301
Hom.:
0
Bravo
AF:
0.0000264
EpiCase
AF:
0.00
EpiControl
AF:
0.0000594

ClinVar

Significance: Likely benign
Submissions summary: Benign:5
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:2
Nov 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Sep 01, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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
-0.43
CADD
Benign
4.0
DANN
Benign
0.77
PhyloP100
-0.87

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: rs767434859; hg19: chr9-138656879; COSMIC: COSV53697124; COSMIC: COSV53697124; API