rs200873319

Variant names:

Your query was ambiguous. Multiple possible variants found:

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_ModerateBS1_SupportingBS2

The NM_001112741.2(KCNC1):c.683G>A(p.Arg228His) variant causes a missense change. The variant allele was found at a frequency of 0.0000316 in 1,614,114 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R228L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

KCNC1
NM_001112741.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.95

Variant links:

Genes affected

KCNC1 (HGNC:6233): (potassium voltage-gated channel subfamily C member 1) This gene encodes a member of a family of integral membrane proteins that mediate the voltage-dependent potassium ion permeability of excitable membranes. Alternative splicing is thought to result in two transcript variants encoding isoforms that differ at their C-termini. These isoforms have had conflicting names in the literature: the longer isoform has been called both "b" and "alpha", while the shorter isoform has been called both "a" and "beta" (PMIDs 1432046, 12091563). [provided by RefSeq, Oct 2014]

KCNC1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.21766424).

BS1

Variant frequency is greater than expected in population eas. gnomad4_exome allele frequency = 0.0000342 (50/1461882) while in subpopulation EAS AF= 0.000151 (6/39698). AF 95% confidence interval is 0.0000651. There are 0 homozygotes in gnomad4_exome. There are 26 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

BS2

High AC in GnomAdExome4 at 50 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNC1	NM_001112741.2 link	c.683G>A	p.Arg228His	missense_variant	Exon 2 of 4	ENST00000265969.8	NP_001106212.1	P48547-2
KCNC1	NM_004976.4 link	c.683G>A	p.Arg228His	missense_variant	Exon 2 of 2		NP_004967.1	P48547-1
KCNC1	XM_047426916.1 link	c.683G>A	p.Arg228His	missense_variant	Exon 2 of 4		XP_047282872.1
KCNC1	XR_930866.3 link	n.1905G>A		non_coding_transcript_exon_variant	Exon 2 of 3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNC1	ENST00000265969.8 link	c.683G>A	p.Arg228His	missense_variant	Exon 2 of 4	5	NM_001112741.2	ENSP00000265969.7		P48547-2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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

GnomAD3 exomes

AF:

0.0000358

AC:

AN:

251490

Hom.:

AF XY:

0.0000441

AC XY:

AN XY:

135918

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000163

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000439

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000342

AC:

AN:

1461882

Hom.:

Cov.:

AF XY:

0.0000358

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000151

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000342

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000227

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.00

AC:

ExAC

AF:

0.0000330

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy type 7

Uncertain:1

Jan 06, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 228 of the KCNC1 protein (p.Arg228His). This variant is present in population databases (rs200873319, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with KCNC1-related conditions. ClinVar contains an entry for this variant (Variation ID: 845316). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt KCNC1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.089

BayesDel_addAF

Benign

-0.062

BayesDel_noAF

Uncertain

-0.060

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.41

T;.

Eigen

Benign

-0.029

Eigen_PC

Benign

0.062

FATHMM_MKL

Uncertain

0.85

LIST_S2

Benign

0.81

T;T

M_CAP

Benign

0.035

MetaRNN

Benign

0.22

T;T

MetaSVM

Uncertain

0.23

MutationAssessor

Benign

1.3

L;L

PrimateAI

Uncertain

0.55

PROVEAN

Benign

-0.67

N;N

REVEL

Uncertain

0.38

Sift

Benign

0.17

T;T

Sift4G

Benign

0.14

T;T

Polyphen

0.90

P;.

Vest4

0.14

MutPred

0.41

Gain of catalytic residue at N229 (P = 0.0722);Gain of catalytic residue at N229 (P = 0.0722);

MVP

0.84

MPC

2.0

ClinPred

0.11

GERP RS

3.8

Varity_R

0.052

gMVP

0.55

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over