rs199473652

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_000891.3(KCNJ2):​c.220A>G​(p.Thr74Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as not provided (no stars). Synonymous variant affecting the same amino acid position (i.e. T74T) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

KCNJ2
NM_000891.3 missense

Scores

16
2
1

Clinical Significance

not provided no classification provided O:1

Conservation

PhyloP100: 9.32

Publications

8 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: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 14 uncertain in NM_000891.3
PM2
Very rare variant in population databases, with high coverage;
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, 0.991

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNJ2NM_000891.3 linkc.220A>G p.Thr74Ala 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.220A>G p.Thr74Ala missense_variant Exon 2 of 2 1 NM_000891.3 ENSP00000243457.2 P63252
KCNJ2ENST00000535240.1 linkc.220A>G p.Thr74Ala missense_variant Exon 2 of 2 1 ENSP00000441848.1 P63252

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461886
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
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:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112004
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
Cov.:
32

ClinVar

Significance: not provided
Submissions summary: Other:1
Revision: no classification provided
LINK: link

Submissions by phenotype

Congenital long QT syndrome Other:1
-
Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

This variant has been reported in the following publications (PMID:15911703;PMID:16541386;PMID:18690034). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.56
D
BayesDel_noAF
Pathogenic
0.57
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.99
D;D
Eigen
Pathogenic
0.85
Eigen_PC
Pathogenic
0.79
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.97
.;D
M_CAP
Pathogenic
0.62
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.8
H;H
PhyloP100
9.3
PrimateAI
Pathogenic
0.88
D
PROVEAN
Pathogenic
-4.4
D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
0.95
P;P
Vest4
0.98
MutPred
0.96
Gain of helix (P = 0.132);Gain of helix (P = 0.132);
MVP
0.97
MPC
1.9
ClinPred
1.0
D
GERP RS
5.7
Varity_R
0.95
gMVP
0.98
Mutation Taster
=1/99
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: rs199473652; hg19: chr17-68171400; API