2-154709738-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PP2PP3_Moderate

The NM_002239.4(KCNJ3):c.838T>A(p.Phe280Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000279 in 1,613,962 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

KCNJ3
NM_002239.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.01

Variant links:

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]

KCNJ3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant where missense usually causes diseases, KCNJ3

PP3

MetaRNN computational evidence supports a deleterious effect, 0.937

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
KCNJ3	NM_002239.4 linkuse as main transcript	c.838T>A	p.Phe280Ile	missense_variant	2/3	ENST00000295101.3
KCNJ3	NM_001260509.2 linkuse as main transcript	c.838T>A	p.Phe280Ile	missense_variant	2/2
KCNJ3	NM_001260508.2 linkuse as main transcript	c.702+10261T>A		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNJ3	ENST00000295101.3 linkuse as main transcript	c.838T>A	p.Phe280Ile	missense_variant	2/3	1	NM_002239.4	P1	P48549-1
KCNJ3	ENST00000544049.2 linkuse as main transcript	c.702+10261T>A		intron_variant		1			P48549-2
KCNJ3	ENST00000651198.1 linkuse as main transcript	c.301T>A	p.Phe101Ile	missense_variant	3/4
KCNJ3	ENST00000493505.1 linkuse as main transcript	n.181T>A		non_coding_transcript_exon_variant	2/3	2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152098

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000318

AC:

AN:

251438

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135888

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000528

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000280

AC:

AN:

1461746

Hom.:

Cov.:

AF XY:

0.0000275

AC XY:

AN XY:

727180

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000112

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.0000306

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152216

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74418

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.0000227

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 20, 2023

The c.838T>A (p.F280I) alteration is located in exon 2 (coding exon 2) of the KCNJ3 gene. This alteration results from a T to A substitution at nucleotide position 838, causing the phenylalanine (F) at amino acid position 280 to be replaced by an isoleucine (I). 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

Pathogenic

0.89

BayesDel_addAF

Pathogenic

0.28

BayesDel_noAF

Pathogenic

0.34

Cadd

Pathogenic

Dann

Uncertain

0.99

DEOGEN2

Pathogenic

0.94

Eigen

Pathogenic

0.94

Eigen_PC

Pathogenic

0.88

FATHMM_MKL

Uncertain

0.97

LIST_S2

Uncertain

0.96

M_CAP

Pathogenic

0.33

MetaRNN

Pathogenic

0.94

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.1

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.90

PROVEAN

Pathogenic

-5.4

REVEL

Pathogenic

0.90

Sift

Uncertain

0.0040

Sift4G

Uncertain

0.020

Polyphen

1.0

Vest4

0.83

MVP

0.81

MPC

2.3

ClinPred

0.89

GERP RS

5.6

Varity_R

0.73

gMVP

0.93

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over