rs74315449

Positions:

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_172201.2(KCNE2):c.79C>A(p.Arg27Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R27H) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

KCNE2
NM_172201.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.70

Variant links:

Genes affected

KCNE2 (HGNC:6242): (potassium voltage-gated channel subfamily E regulatory subunit 2) Voltage-gated potassium (Kv) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a member of the potassium channel, voltage-gated, isk-related subfamily. This member is a small integral membrane subunit that assembles with the KCNH2 gene product, a pore-forming protein, to alter its function. This gene is expressed in heart and muscle and the gene mutations are associated with cardiac arrhythmia. [provided by RefSeq, Jul 2008]

KCNE2 links:

(HGNC:):

links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2

High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
KCNE2	NM_172201.2 linkuse as main transcript	c.79C>A	p.Arg27Ser	missense_variant	2/2	ENST00000290310.4	NP_751951.1
LOC105372791	XR_937683.3 linkuse as main transcript	n.1297G>T		non_coding_transcript_exon_variant	2/2
LOC105372791	XR_007067848.1 linkuse as main transcript	n.1332G>T		non_coding_transcript_exon_variant	2/2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNE2	ENST00000290310.4 linkuse as main transcript	c.79C>A	p.Arg27Ser	missense_variant	2/2	1	NM_172201.2	ENSP00000290310	P1
	ENST00000440403.2 linkuse as main transcript	n.732G>T		non_coding_transcript_exon_variant	2/3	3

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251466

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000821

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000108

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.00000747

Hom.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 01, 2021

Variant summary: KCNE2 c.79C>A (p.Arg27Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251466 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.79C>A has been reported in the literature in at-least one individual affected with Arrhythmia in a study cohort of index cases and families among surveyed inherited arrythmia clinics and the Rochester Long-QT syndrome registry (example, Roberts_2017). This report does not provide unequivocal conclusions about association of the variant with Arrhythmia/LQT6. At-least one co-occurrence with another pathogenic variant has been observed at our laboratory (PKP2 c.2489+1G>A), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Long QT syndrome 6

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 20, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 1172865). This missense change has been observed in individual(s) with long QT syndrome (PMID: 28794082). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 27 of the KCNE2 protein (p.Arg27Ser). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.43

BayesDel_addAF

Pathogenic

0.41

BayesDel_noAF

Pathogenic

0.36

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.35

Eigen

Uncertain

0.39

Eigen_PC

Uncertain

0.32

FATHMM_MKL

Benign

0.76

LIST_S2

Benign

0.67

M_CAP

Pathogenic

0.32

MetaRNN

Uncertain

0.58

MetaSVM

Pathogenic

0.81

MutationAssessor

Uncertain

2.4

MutationTaster

Benign

0.99

PrimateAI

Benign

0.33

PROVEAN

Benign

-1.3

REVEL

Pathogenic

0.68

Sift

Uncertain

0.0020

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.32

MVP

0.96

MPC

0.38

ClinPred

0.98

GERP RS

4.6

Varity_R

0.33

gMVP

0.93

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

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