2-154699377-T-C

Position:

• chr2-154699377-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_002239.4(KCNJ3):​c.602T>C​(p.Val201Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: KCNJ3 NM_002239.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.90

Genes affected

KCNJ3 (HGNC:6264): (potassium inwardly rectifying channel subfamily J member 3) 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, is controlled by G-proteins and plays an important role in regulating heartbeat. It associates with three other G-protein-activated potassium channels to form a heteromultimeric pore-forming complex that also couples to neurotransmitter receptors in the brain and whereby channel activation can inhibit action potential firing by hyperpolarizing the plasma membrane. These multimeric G-protein-gated inwardly-rectifying potassium (GIRK) channels may play a role in the pathophysiology of epilepsy, addiction, Down's syndrome, ataxia, and Parkinson's disease. Alternative splicing results in multiple transcript variants encoding distinct proteins. [provided by RefSeq, May 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNJ3	NM_002239.4	c.602T>C	p.Val201Ala	missense_variant	1/3	ENST00000295101.3	NP_002230.1
KCNJ3	NM_001260509.2	c.602T>C	p.Val201Ala	missense_variant	1/2		NP_001247438.1
KCNJ3	NM_001260510.2	c.602T>C	p.Val201Ala	missense_variant	1/1		NP_001247439.1
KCNJ3	NM_001260508.2	c.602T>C	p.Val201Ala	missense_variant	1/2		NP_001247437.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNJ3	ENST00000295101.3	c.602T>C	p.Val201Ala	missense_variant	1/3	1	NM_002239.4	ENSP00000295101	P1
KCNJ3	ENST00000544049.2	c.602T>C	p.Val201Ala	missense_variant	1/2	1		ENSP00000438410
KCNJ3	ENST00000651198.1	c.65T>C	p.Val22Ala	missense_variant	2/4			ENSP00000498639

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 30, 2024

The c.602T>C (p.V201A) alteration is located in exon 1 (coding exon 1) of the KCNJ3 gene. This alteration results from a T to C substitution at nucleotide position 602, causing the valine (V) at amino acid position 201 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.030
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.97	D;.
Eigen	Uncertain	0.28
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Benign	0.74	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.58	D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Uncertain	2.7	M;M
MutationTaster	Benign	0.96	D;D
PrimateAI	Uncertain	0.75	T
PROVEAN	Uncertain	-3.4	D;D
REVEL	Pathogenic	0.67
Sift	Benign	0.062	T;D
Sift4G	Benign	0.092	T;D
Polyphen		0.028	B;.
Vest4		0.25
MutPred		0.86		Gain of disorder (P = 0.0785);Gain of disorder (P = 0.0785);
MVP		0.91
MPC		2.0
ClinPred		0.97	D
GERP RS		5.6
Varity_R		0.23
gMVP		0.92

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-155555889;