9-135786359-C-T

Variant summary

Our verdict is Benign. The variant received -18 ACMG points: 0P and 18B. BP4_ModerateBP6_Very_StrongBS1BS2

The NM_020822.3(KCNT1):​c.3340C>T​(p.Arg1114Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000504 in 1,582,344 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1114Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00037 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00052 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

2
11
5

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:9

Conservation

PhyloP100: 2.79

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: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
  • malignant migrating partial seizures of infancy
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, G2P
  • 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 -18 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.18138194).
BP6
Variant 9-135786359-C-T is Benign according to our data. Variant chr9-135786359-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 211243.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 = 0.000368 (56/152278) while in subpopulation AMR AF = 0.000979 (15/15314). AF 95% confidence interval is 0.000603. There are 0 homozygotes in GnomAd4. There are 23 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High AC in GnomAd4 at 56 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020822.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
KCNT1
NM_020822.3
MANE Select
c.3340C>Tp.Arg1114Trp
missense
Exon 29 of 31NP_065873.2Q5JUK3-3
KCNT1
NM_001272003.2
c.3205C>Tp.Arg1069Trp
missense
Exon 28 of 31NP_001258932.1Q5JUK3-4

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
KCNT1
ENST00000371757.7
TSL:1 MANE Select
c.3340C>Tp.Arg1114Trp
missense
Exon 29 of 31ENSP00000360822.2Q5JUK3-3
KCNT1
ENST00000460750.5
TSL:1
n.*2950C>T
non_coding_transcript_exon
Exon 29 of 32ENSP00000418777.1F8WC49
KCNT1
ENST00000460750.5
TSL:1
n.*2950C>T
3_prime_UTR
Exon 29 of 32ENSP00000418777.1F8WC49

Frequencies

GnomAD3 genomes
AF:
0.000368
AC:
56
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000981
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:
0.000544
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000337
AC:
61
AN:
181208
AF XY:
0.000380
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000899
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000446
Gnomad OTH exome
AF:
0.000418
GnomAD4 exome
AF:
0.000518
AC:
741
AN:
1430066
Hom.:
0
Cov.:
36
AF XY:
0.000524
AC XY:
371
AN XY:
708426
show subpopulations
African (AFR)
AF:
0.0000913
AC:
3
AN:
32864
American (AMR)
AF:
0.000837
AC:
33
AN:
39432
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25446
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38338
South Asian (SAS)
AF:
0.0000723
AC:
6
AN:
82944
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49384
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4922
European-Non Finnish (NFE)
AF:
0.000594
AC:
652
AN:
1097570
Other (OTH)
AF:
0.000794
AC:
47
AN:
59166
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
47
94
140
187
234
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
30
60
90
120
150
<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:
0.000368
AC:
56
AN:
152278
Hom.:
0
Cov.:
33
AF XY:
0.000309
AC XY:
23
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.0000722
AC:
3
AN:
41572
American (AMR)
AF:
0.000979
AC:
15
AN:
15314
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5160
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.000544
AC:
37
AN:
67988
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
4
8
12
16
20
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:
0.0000435
Hom.:
0
Bravo
AF:
0.000589
ESP6500AA
AF:
0.000277
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000231
AC:
26
Asia WGS
AF:
0.000289
AC:
1
AN:
3470

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
3
not provided (3)
-
1
1
not specified (2)
-
-
1
Autosomal dominant nocturnal frontal lobe epilepsy 5 (1)
-
-
1
Developmental and epileptic encephalopathy, 14 (1)
-
-
1
Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 (1)
-
-
1
Inborn genetic diseases (1)
-
-
1
KCNT1-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.29
BayesDel_addAF
Benign
-0.064
T
BayesDel_noAF
Uncertain
0.060
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.27
T
Eigen
Uncertain
0.41
Eigen_PC
Uncertain
0.29
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Pathogenic
1.0
D
M_CAP
Pathogenic
0.46
D
MetaRNN
Benign
0.18
T
MetaSVM
Benign
-0.69
T
MutationAssessor
Uncertain
2.3
M
PhyloP100
2.8
PrimateAI
Uncertain
0.66
T
PROVEAN
Uncertain
-3.1
D
REVEL
Uncertain
0.34
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.045
D
Vest4
0.74
MVP
0.62
MPC
0.39
ClinPred
0.095
T
GERP RS
3.8
Varity_R
0.17
gMVP
0.48
Mutation Taster
=59/41
polymorphism

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: rs370085077; hg19: chr9-138678205; API