11-74457286-T-C

Variant summary

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

The NM_005472.5(KCNE3):c.278A>G(p.His93Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,740 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. H93Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KCNE3 NM_005472.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.54

Genes affected

KCNE3 (HGNC:6243): (potassium voltage-gated channel subfamily E regulatory subunit 3) 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 type I membrane protein, and a beta subunit that assembles with a potassium channel alpha-subunit to modulate the gating kinetics and enhance stability of the multimeric complex. This gene is prominently expressed in the kidney. A missense mutation in this gene is associated with hypokalemic periodic paralysis. [provided by RefSeq, Jul 2008]

(HGNC:):

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	UniProt
KCNE3	NM_005472.5	c.278A>G	p.His93Arg	missense_variant	3/3	ENST00000310128.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNE3	ENST00000310128.9	c.278A>G	p.His93Arg	missense_variant	3/3	1	NM_005472.5	P1
KCNE3	ENST00000525550.1	c.278A>G	p.His93Arg	missense_variant	2/2	1		P1
	ENST00000533008.1	n.155-26891T>C		intron_variant, non_coding_transcript_variant		3
KCNE3	ENST00000532569.5	c.278A>G	p.His93Arg	missense_variant	3/3	4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461740 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727176

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 11, 2023

The p.H93R variant (also known as c.278A>G), located in coding exon 1 of the KCNE3 gene, results from an A to G substitution at nucleotide position 278. The histidine at codon 93 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.49
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
Cadd	Uncertain	26
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;D;.
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Uncertain	0.87	D
M_CAP	Uncertain	0.11	D
MetaRNN	Uncertain	0.73	D;D;D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Uncertain	2.1	M;M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-5.1	D;D;D
REVEL	Pathogenic	0.75
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;.
Polyphen		1.0	D;D;.
Vest4		0.81
MutPred		0.34		Gain of MoRF binding (P = 0.0101);Gain of MoRF binding (P = 0.0101);Gain of MoRF binding (P = 0.0101);
MVP		0.99
MPC		0.63
ClinPred		0.99	D
GERP RS		5.2
Varity_R		0.93
gMVP		0.96

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

Other links and lift over

dbSNP: rs1329138899; hg19: chr11-74168331;