rs769422518

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_020822.3(KCNT1):​c.3298G>A​(p.Ala1100Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000194 in 1,599,978 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A1100V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000017 ( 1 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

1
17

Clinical Significance

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

Conservation

PhyloP100: 2.12

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: 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 -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.08517137).
BP6
Variant 9-135786317-G-A is Benign according to our data. Variant chr9-135786317-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 473386.
BS2
High AC in GnomAd4 at 7 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.3298G>Ap.Ala1100Thr
missense
Exon 29 of 31NP_065873.2Q5JUK3-3
KCNT1
NM_001272003.2
c.3163G>Ap.Ala1055Thr
missense
Exon 28 of 31NP_001258932.1Q5JUK3-4

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
KCNT1
ENST00000371757.7
TSL:1 MANE Select
c.3298G>Ap.Ala1100Thr
missense
Exon 29 of 31ENSP00000360822.2Q5JUK3-3
KCNT1
ENST00000460750.5
TSL:1
n.*2908G>A
non_coding_transcript_exon
Exon 29 of 32ENSP00000418777.1F8WC49
KCNT1
ENST00000460750.5
TSL:1
n.*2908G>A
3_prime_UTR
Exon 29 of 32ENSP00000418777.1F8WC49

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152146
Hom.:
0
Cov.:
33
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:
0.000103
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000193
AC:
4
AN:
207676
AF XY:
0.00000871
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000451
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000166
AC:
24
AN:
1447832
Hom.:
1
Cov.:
36
AF XY:
0.0000153
AC XY:
11
AN XY:
719030
show subpopulations
African (AFR)
AF:
0.0000300
AC:
1
AN:
33312
American (AMR)
AF:
0.00
AC:
0
AN:
42618
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25724
East Asian (EAS)
AF:
0.0000255
AC:
1
AN:
39146
South Asian (SAS)
AF:
0.0000237
AC:
2
AN:
84404
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50494
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5414
European-Non Finnish (NFE)
AF:
0.0000172
AC:
19
AN:
1106904
Other (OTH)
AF:
0.0000167
AC:
1
AN:
59816
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
2
3
5
6
8
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152146
Hom.:
0
Cov.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000103
AC:
7
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.539
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00
Hom.:
0
Bravo
AF:
0.0000378
ExAC
AF:
0.0000173
AC:
2

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
1
-
Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 (1)
-
-
1
Inborn genetic diseases (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.066
BayesDel_addAF
Benign
-0.36
T
BayesDel_noAF
Benign
-0.76
CADD
Benign
15
DANN
Benign
0.95
DEOGEN2
Benign
0.022
T
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.28
N
LIST_S2
Benign
0.67
T
M_CAP
Uncertain
0.18
D
MetaRNN
Benign
0.085
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.41
N
PhyloP100
2.1
PrimateAI
Benign
0.42
T
PROVEAN
Benign
-0.22
N
REVEL
Benign
0.016
Sift
Benign
0.32
T
Sift4G
Benign
0.18
T
Vest4
0.15
MVP
0.23
MPC
0.086
ClinPred
0.042
T
GERP RS
1.4
Varity_R
0.020
gMVP
0.36
Mutation Taster
=89/11
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.080
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: rs769422518; hg19: chr9-138678163; COSMIC: COSV53698810; COSMIC: COSV53698810; API