rs976664434

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP2PP3

The NM_001378969.1(KCND3):​c.1496C>G​(p.Ser499Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000186 in 1,613,858 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 (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

KCND3
NM_001378969.1 missense

Scores

3
9
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.06

Publications

0 publications found
Variant links:
Genes affected
KCND3 (HGNC:6239): (potassium voltage-gated channel subfamily D member 3) Voltage-gated potassium (Kv) 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. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shal-related subfamily, members of which form voltage-activated A-type potassium ion channels and are prominent in the repolarization phase of the action potential. This member includes two isoforms with different sizes, which are encoded by alternatively spliced transcript variants of this gene. [provided by RefSeq, Jul 2008]
KCND3 Gene-Disease associations (from GenCC):
  • neurodevelopmental disorder
    Inheritance: AD Classification: STRONG Submitted by: G2P
  • spinocerebellar ataxia type 19/22
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, Ambry Genetics
  • Brugada syndrome 9
    Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp
  • Brugada syndrome 1
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the KCND3 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 20 curated pathogenic missense variants (we use a threshold of 10). The gene has 4 curated benign missense variants. Gene score misZ: 3.8545 (above the threshold of 3.09). Trascript score misZ: 4.8782 (above the threshold of 3.09). GenCC associations: The gene is linked to spinocerebellar ataxia type 19/22, neurodevelopmental disorder, Brugada syndrome 1, Brugada syndrome 9.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.806

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCND3NM_001378969.1 linkc.1496C>G p.Ser499Cys missense_variant Exon 6 of 8 ENST00000302127.5 NP_001365898.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCND3ENST00000302127.5 linkc.1496C>G p.Ser499Cys missense_variant Exon 6 of 8 5 NM_001378969.1 ENSP00000306923.4 Q9UK17-1
KCND3ENST00000315987.6 linkc.1496C>G p.Ser499Cys missense_variant Exon 6 of 8 1 ENSP00000319591.2 Q9UK17-1
KCND3ENST00000369697.5 linkc.1462-1185C>G intron_variant Intron 4 of 5 1 ENSP00000358711.1 Q9UK17-2
KCND3ENST00000703640.1 linkn.2153-1185C>G intron_variant Intron 2 of 2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152174
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251460
AF XY:
0.00
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:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461684
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727164
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111834
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60378
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
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152174
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41414
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000264

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Spinocerebellar ataxia type 19/22;C4225340:Brugada syndrome 9 Uncertain:1
Jul 29, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Jun 18, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.S499C variant (also known as c.1496C>G), located in coding exon 5 of the KCND3 gene, results from a C to G substitution at nucleotide position 1496. The serine at codon 499 is replaced by cysteine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Spinocerebellar ataxia type 19/22 Uncertain:1
Dec 06, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 499 of the KCND3 protein (p.Ser499Cys). This variant is present in population databases (no rsID available, gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KCND3-related conditions. ClinVar contains an entry for this variant (Variation ID: 570216). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Uncertain
0.13
CADD
Uncertain
25
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.53
D
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.54
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.75
T
M_CAP
Pathogenic
0.29
D
MetaRNN
Pathogenic
0.81
D
MetaSVM
Uncertain
0.78
D
MutationAssessor
Benign
1.4
L
PhyloP100
7.1
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
-0.45
N
REVEL
Uncertain
0.59
Sift
Benign
0.15
T
Sift4G
Benign
0.16
T
Polyphen
0.84
P
Vest4
0.80
MutPred
0.48
Loss of disorder (P = 0.0727);
MVP
0.65
MPC
0.34
ClinPred
0.89
D
GERP RS
5.1
Varity_R
0.23
gMVP
0.50
Mutation Taster
=66/34
polymorphism

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: rs976664434; hg19: chr1-112321080; API