KCNJ2 p.Asn32Lys

Variant names:

• chr17-70175135-C-A
• rs67120636
• NM_000891.3:c.96C>A
• KCNJ2 p.Asn32Lys

Your query was ambiguous. Multiple possible variants found:

• chr17-70175135-C-A
• chr17-70175135-C-G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_000891.3(KCNJ2):​c.96C>A​(p.Asn32Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Synonymous variant affecting the same amino acid position (i.e. N32N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: KCNJ2 NM_000891.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.02
• Publications: 0 publications found

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, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
• short QT syndrome type 3

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P
• short QT syndrome

  Inheritance: AD Classification: MODERATE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• 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
• congenital heart disease

  Inheritance: Unknown Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• 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, catecholaminergic polymorphic ventricular tachycardia, long QT syndrome, familial atrial fibrillation, congenital heart disease.
• BP4: Computational evidence support a benign effect (MetaRNN=0.33487964).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000891.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNJ2	NM_000891.3	MANE Select	c.96C>A	p.Asn32Lys	missense	Exon 2 of 2	NP_000882.1	P63252

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNJ2	ENST00000243457.4	TSL:1 MANE Select	c.96C>A	p.Asn32Lys	missense	Exon 2 of 2	ENSP00000243457.2	P63252
	KCNJ2	ENST00000535240.1	TSL:1	c.96C>A	p.Asn32Lys	missense	Exon 2 of 2	ENSP00000441848.1	P63252
	KCNJ2	ENST00000854891.1		c.96C>A	p.Asn32Lys	missense	Exon 3 of 3	ENSP00000524950.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461874 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727240

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: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111994

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.50
CADD	Benign	5.8
DANN	Uncertain	0.98
DEOGEN2	Benign	0.38	T
Eigen	Benign	-0.63
Eigen_PC	Benign	-0.85
FATHMM_MKL	Benign	0.17	N
LIST_S2	Uncertain	0.93	D
M_CAP	Benign	0.034	D
MetaRNN	Benign	0.33	T
MetaSVM	Benign	-0.62	T
MutationAssessor	Uncertain	2.8	M
PhyloP100		-1.0
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-1.6	N
REVEL	Benign	0.28
Sift	Benign	0.032	D
Sift4G	Benign	0.41	T
Varity_R		0.30
gMVP		0.98
Mutation Taster		=55/45	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs67120636;

hg19: chr17-68171276;