chr9-135784588-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.2997C>T​(p.Asp999Asp) variant causes a synonymous change. The variant allele was found at a frequency of 0.0000113 in 1,594,496 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 0.0000067 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

2

Clinical Significance

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

Conservation

PhyloP100: 4.53

Publications

0 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 -18 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.43).
BP6
Variant 9-135784588-C-T is Benign according to our data. Variant chr9-135784588-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 241302.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population amr. GnomAdExome4 allele frequency = 0.0000118 (17/1444438) while in subpopulation AMR AF = 0.000387 (17/43966). AF 95% confidence interval is 0.000245. There are 0 homozygotes in GnomAdExome4. There are 9 alleles in the male GnomAdExome4 subpopulation. Median coverage is 34. This position passed quality control check.
BS2
High AC in GnomAdExome4 at 17 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.2997C>T p.Asp999Asp synonymous_variant Exon 26 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.2997C>T p.Asp999Asp synonymous_variant Exon 26 of 31 1 NM_020822.3 ENSP00000360822.2 Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.00000666
AC:
1
AN:
150058
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000670
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000575
AC:
14
AN:
243548
AF XY:
0.0000527
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000410
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000118
AC:
17
AN:
1444438
Hom.:
0
Cov.:
34
AF XY:
0.0000125
AC XY:
9
AN XY:
718334
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33208
American (AMR)
AF:
0.000387
AC:
17
AN:
43966
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25082
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39092
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85796
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51330
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4560
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1102250
Other (OTH)
AF:
0.00
AC:
0
AN:
59154
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000666
AC:
1
AN:
150058
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
73130
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
40868
American (AMR)
AF:
0.0000670
AC:
1
AN:
14932
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3444
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5008
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4664
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10318
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
312
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67534
Other (OTH)
AF:
0.00
AC:
0
AN:
2076
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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189

ClinVar

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

Submissions by phenotype

not specified Benign:1
Mar 27, 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
Oct 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
Sep 06, 2016
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
-0.43
CADD
Benign
9.7
DANN
Benign
0.61
PhyloP100
4.5

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: rs771951768; hg19: chr9-138676434; API