rs202067116

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 5P and 4B. PM1PP2PP3_ModerateBS2

The NM_000891.3(KCNJ2):​c.973C>T​(p.Arg325Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000582 in 1,614,048 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R325H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000057 ( 0 hom. )

Consequence

KCNJ2
NM_000891.3 missense

Scores

17
1
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 7.91

Publications

5 publications found
Variant links:
Genes affected
KCNJ2 (HGNC:6263): (potassium inwardly rectifying channel subfamily J member 2) Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, probably participates in establishing action potential waveform and excitability of neuronal and muscle tissues. Mutations in this gene have been associated with Andersen syndrome, which is characterized by periodic paralysis, cardiac arrhythmias, and dysmorphic features. [provided by RefSeq, Jul 2008]
KCNJ2 Gene-Disease associations (from GenCC):
  • Andersen-Tawil syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • short QT syndrome type 3
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • short QT syndrome
    Inheritance: AD Classification: MODERATE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • familial atrial fibrillation
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • catecholaminergic polymorphic ventricular tachycardia
    Inheritance: AD Classification: LIMITED, NO_KNOWN Submitted by: ClinGen, Genomics England PanelApp
  • long QT syndrome
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM1
In a topological_domain Cytoplasmic (size 248) in uniprot entity KCNJ2_HUMAN there are 35 pathogenic changes around while only 8 benign (81%) in NM_000891.3
PP2
Missense variant in the KCNJ2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 51 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 2.7459 (below the threshold of 3.09). Trascript score misZ: 3.9347 (above the threshold of 3.09). GenCC associations: The gene is linked to short QT syndrome type 3, short QT syndrome, Andersen-Tawil syndrome, familial atrial fibrillation, catecholaminergic polymorphic ventricular tachycardia, long QT syndrome.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.922
BS2
High AC in GnomAd4 at 11 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNJ2NM_000891.3 linkc.973C>T p.Arg325Cys missense_variant Exon 2 of 2 ENST00000243457.4 NP_000882.1 P63252

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNJ2ENST00000243457.4 linkc.973C>T p.Arg325Cys missense_variant Exon 2 of 2 1 NM_000891.3 ENSP00000243457.2 P63252
KCNJ2ENST00000535240.1 linkc.973C>T p.Arg325Cys missense_variant Exon 2 of 2 1 ENSP00000441848.1 P63252

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152062
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000944
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000398
AC:
10
AN:
251358
AF XY:
0.0000442
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.0000924
Gnomad NFE exome
AF:
0.0000528
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000568
AC:
83
AN:
1461868
Hom.:
0
Cov.:
32
AF XY:
0.0000564
AC XY:
41
AN XY:
727232
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86258
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000638
AC:
71
AN:
1111990
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.459
Heterozygous variant carriers
0
5
10
16
21
26
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000723
AC:
11
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.0000806
AC XY:
6
AN XY:
74400
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41512
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5168
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.0000944
AC:
1
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68012
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.443
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000354
Hom.:
0
Bravo
AF:
0.0000604
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Andersen Tawil syndrome;C1865018:Short QT syndrome type 3 Uncertain:1
Jan 01, 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 cysteine, which is neutral and slightly polar, at codon 325 of the KCNJ2 protein (p.Arg325Cys). This variant is present in population databases (rs202067116, gnomAD 0.02%). This missense change has been observed in individual(s) with arrhythmogenic disorders and/or long QT syndrome (PMID: 27920829, 30975432, 31737537). ClinVar contains an entry for this variant (Variation ID: 190821). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on KCNJ2 protein function. 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. -

Ventricular fibrillation Uncertain:1
May 22, 2015
Blueprint Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Sep 18, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has been reported in one individual with LQTS; however this individual also harbored a pathogenic variant in a second cardiac gene related to LQTS (Burns et al., 2016); Also reported as a variant of uncertain significant in a adult male with sudden cardiac arrest and no prior cardiac phenotype; additional information, such segregation or functional studies were not specified in this report (Asatryan et al., 2019); Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 27920829, 30975432, 31737537) -

Andersen Tawil syndrome Uncertain:1
Mar 17, 2017
Center For Human Genetics And Laboratory Diagnostics, Dr. Klein, Dr. Rost And Colleagues
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Sep 27, 2022
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.78
BayesDel_addAF
Pathogenic
0.37
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.96
D;D
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.82
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
.;D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.92
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.5
H;H
PhyloP100
7.9
PrimateAI
Pathogenic
0.85
D
PROVEAN
Pathogenic
-7.3
D;D
REVEL
Pathogenic
0.86
Sift
Uncertain
0.0040
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
0.99
D;D
Vest4
0.91
MVP
0.95
MPC
2.2
ClinPred
0.81
D
GERP RS
5.7
Varity_R
0.69
gMVP
0.88
Mutation Taster
=9/91
disease causing

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: rs202067116; hg19: chr17-68172153; API