rs1554991314

Positions:

chr11-17771786-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PM5PP2PP3

The NM_001112741.2(KCNC1):c.692C>T(p.Thr231Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. T231A) has been classified as Likely pathogenic.

Frequency

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

Exomes 𝑓: 0.0000021 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

KCNC1
NM_001112741.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.91

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 Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr11-17771785-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 568146.Status of the report is criteria_provided_single_submitter, 1 stars.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNC1. . Gene score misZ 4.5189 (greater than the threshold 3.09). Trascript score misZ 5.1707 (greater than threshold 3.09). GenCC has associacion of gene with progressive myoclonic epilepsy type 7, progressive myoclonus epilepsy, complex neurodevelopmental disorder.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.78

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
KCNC1	NM_001112741.2 linkuse as main transcript	c.692C>T	p.Thr231Met	missense_variant	2/4	ENST00000265969.8
KCNC1	NM_004976.4 linkuse as main transcript	c.692C>T	p.Thr231Met	missense_variant	2/2
KCNC1	XM_047426916.1 linkuse as main transcript	c.692C>T	p.Thr231Met	missense_variant	2/4
KCNC1	XR_930866.3 linkuse as main transcript	n.1914C>T		non_coding_transcript_exon_variant	2/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNC1	ENST00000265969.8 linkuse as main transcript	c.692C>T	p.Thr231Met	missense_variant	2/4	5	NM_001112741.2	P1	P48547-2

Frequencies

GnomAD3 genomes

AF:

0.00

AC:

AN:

152246

Hom.:

Cov.:

FAILED QC

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Data not reliable, filtered out with message: AS_VQSR

AF:

0.00000656

AC:

AN:

152364

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74510

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000439

Hom.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy type 7

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 24, 2017

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. This variant has not been reported in the literature in individuals with KCNC1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces threonine with methionine at codon 231 of the KCNC1 protein (p.Thr231Met). The threonine residue is highly conserved and there is a moderate physicochemical difference between threonine and methionine. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jan 13, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.35

BayesDel_addAF

Pathogenic

0.37

BayesDel_noAF

Pathogenic

0.29

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.86

D;.

Eigen

Pathogenic

0.70

Eigen_PC

Uncertain

0.66

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.84

T;T

M_CAP

Uncertain

0.24

MetaRNN

Pathogenic

0.78

D;D

MetaSVM

Uncertain

0.58

MutationAssessor

Pathogenic

3.3

M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.79

PROVEAN

Uncertain

-3.3

D;D

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0060

D;D

Sift4G

Uncertain

0.017

D;D

Polyphen

1.0

D;.

Vest4

0.53

MutPred

0.38

Loss of phosphorylation at T231 (P = 0.0365);Loss of phosphorylation at T231 (P = 0.0365);

MVP

0.92

MPC

2.6

ClinPred

0.99

GERP RS

4.7

Varity_R

0.13

gMVP

0.84

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