21-34449460-G-C

Position:

• chr21-34449460-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM5 BP4_Moderate

The NM_000219.6(KCNE1):​c.175C>G​(p.Leu59Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. 12/21 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. L59P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 17)
• Consequence: KCNE1 NM_000219.6 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.79

Genes affected

KCNE1 (HGNC:6240): (potassium voltage-gated channel subfamily E regulatory subunit 1) The product of this gene belongs to the potassium channel KCNE family. Potassium ion channels are essential to many cellular functions and show a high degree of diversity, varying in their electrophysiologic and pharmacologic properties. This gene encodes a transmembrane protein known to associate with the product of the KVLQT1 gene to form the delayed rectifier potassium channel. Mutation in this gene are associated with both Jervell and Lange-Nielsen and Romano-Ward forms of long-QT syndrome. Alternatively spliced transcript variants encoding the same protein have been identified. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000219.6
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr21-34449459-A-G is described in Lovd as [Pathogenic].
• BP4: Computational evidence support a benign effect (MetaRNN=0.12141049).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNE1	NM_000219.6	c.175C>G	p.Leu59Val	missense_variant	4/4	ENST00000399286.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNE1	ENST00000399286.3	c.175C>G	p.Leu59Val	missense_variant	4/4	1	NM_000219.6	P1

Frequencies

GnomAD3 genomes Cov.: 17

GnomAD4 exome Cov.: 19

GnomAD4 genome Cov.: 17

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.00 AC: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.016	T
BayesDel_noAF	Uncertain	-0.060
CADD	Benign	19
DANN	Uncertain	0.98
DEOGEN2	Benign	0.42	T;T;T;T;T;T;T;T
Eigen	Benign	-0.19
Eigen_PC	Benign	-0.017
FATHMM_MKL	Benign	0.74	D
M_CAP	Benign	0.034	D
MetaRNN	Benign	0.12	T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.14	T
MutationAssessor	Uncertain	2.3	M;M;M;M;M;M;M;M
MutationTaster	Benign	0.52	D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Benign	0.42	T
PROVEAN	Benign	0.060	N;.;.;N;N;N;N;N
REVEL	Uncertain	0.34
Sift	Benign	0.38	T;.;.;T;T;T;T;T
Sift4G	Benign	0.19	T;T;T;T;T;T;T;T
Polyphen		0.027	B;B;B;B;B;B;B;B
Vest4		0.046
MutPred		0.22		Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);Loss of helix (P = 0.1299);
MVP		0.81
MPC		0.11
ClinPred		0.44	T
GERP RS		4.1
Varity_R		0.057
gMVP		0.59

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: rs754731040; hg19: chr21-35821758;