chr9-135770050-C-T

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_020822.3(KCNT1):​c.1614C>T​(p.Arg538=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000942 in 1,549,910 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000096 ( 2 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

2

Clinical Significance

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

Conservation

PhyloP100: -2.05
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]

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.75).
BP6
Variant 9-135770050-C-T is Benign according to our data. Variant chr9-135770050-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 383992.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-135770050-C-T is described in Lovd as [Likely_benign].
BP7
Synonymous conserved (PhyloP=-2.05 with no splicing effect.
BS1
Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.0000788 (12/152340) while in subpopulation SAS AF= 0.00124 (6/4834). AF 95% confidence interval is 0.00054. There are 0 homozygotes in gnomad4. There are 6 alleles in male gnomad4 subpopulation. Median coverage is 34. This position pass quality control queck.
BS2
High AC in GnomAd4 at 12 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
KCNT1NM_020822.3 linkuse as main transcriptc.1614C>T p.Arg538= synonymous_variant 16/31 ENST00000371757.7 NP_065873.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
KCNT1ENST00000371757.7 linkuse as main transcriptc.1614C>T p.Arg538= synonymous_variant 16/311 NM_020822.3 ENSP00000360822 A2Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.0000854
AC:
13
AN:
152222
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000965
Gnomad SAS
AF:
0.00124
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.000378
AC:
58
AN:
153406
Hom.:
0
AF XY:
0.000345
AC XY:
28
AN XY:
81108
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000402
Gnomad ASJ exome
AF:
0.000120
Gnomad EAS exome
AF:
0.00290
Gnomad SAS exome
AF:
0.000790
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000173
Gnomad OTH exome
AF:
0.000920
GnomAD4 exome
AF:
0.0000959
AC:
134
AN:
1397570
Hom.:
2
Cov.:
32
AF XY:
0.000104
AC XY:
72
AN XY:
689524
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000278
Gnomad4 ASJ exome
AF:
0.0000398
Gnomad4 EAS exome
AF:
0.000949
Gnomad4 SAS exome
AF:
0.000909
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000463
Gnomad4 OTH exome
AF:
0.000363
GnomAD4 genome
AF:
0.0000788
AC:
12
AN:
152340
Hom.:
0
Cov.:
34
AF XY:
0.0000806
AC XY:
6
AN XY:
74480
show subpopulations
Gnomad4 AFR
AF:
0.0000240
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000773
Gnomad4 SAS
AF:
0.00124
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.000473
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000831
Asia WGS
AF:
0.00144
AC:
5
AN:
3478

ClinVar

Significance: Benign/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:1
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 22, 2024- -
KCNT1-related disorder Benign:1
Likely benign, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesApr 01, 2019This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -
not provided Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxNov 03, 2020- -
Developmental and epileptic encephalopathy, 14 Benign:1
Likely benign, criteria provided, single submitterclinical testingGenome-Nilou LabMar 15, 2022- -
Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Likely benign, criteria provided, single submitterclinical testingGenome-Nilou LabMar 15, 2022- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.75
CADD
Benign
5.0
DANN
Benign
0.92

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs368876173; hg19: chr9-138661896; API