rs368011737

chr11-2571364-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3_Moderate PP5

The NM_000218.3(KCNQ1):c.644T>G(p.Val215Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000657 in 152,110 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V215M) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: KCNQ1 NM_000218.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2
• Conservation: PhyloP100: 5.85

Genes affected

KCNQ1 (HGNC:6294): (potassium voltage-gated channel subfamily Q member 1) This gene encodes a voltage-gated potassium channel required for repolarization phase of the cardiac action potential. This protein can form heteromultimers with two other potassium channel proteins, KCNE1 and KCNE3. Mutations in this gene are associated with hereditary long QT syndrome 1 (also known as Romano-Ward syndrome), Jervell and Lange-Nielsen syndrome, and familial atrial fibrillation. This gene exhibits tissue-specific imprinting, with preferential expression from the maternal allele in some tissues, and biallelic expression in others. This gene is located in a region of chromosome 11 amongst other imprinted genes that are associated with Beckwith-Wiedemann syndrome (BWS), and itself has been shown to be disrupted by chromosomal rearrangements in patients with BWS. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 10 uncertain in NM_000218.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-2571363-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 53081.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1, Likely_pathogenic=2, not_provided=1}.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.9
• PP5: Variant 11-2571364-T-G is Pathogenic according to our data. Variant chr11-2571364-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 456868.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3	c.644T>G	p.Val215Gly	missense_variant	4/16	ENST00000155840.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12	c.644T>G	p.Val215Gly	missense_variant	4/16	1	NM_000218.3	P1
KCNQ1	ENST00000335475.6	c.263T>G	p.Val88Gly	missense_variant	4/16	1
KCNQ1	ENST00000496887.7	c.383T>G	p.Val128Gly	missense_variant	5/16	5
KCNQ1	ENST00000646564.2	c.478-12071T>G		intron_variant

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152110 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250346 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135652

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: 0.00000885

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 32

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152110 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74314

Gnomad4 AFR AF: 0.0000241

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: 0.00

Gnomad4 OTH AF: 0.00

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Long QT syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Oct 31, 2022

Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 30571187). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KCNQ1 protein function. ClinVar contains an entry for this variant (Variation ID: 456868). This missense change has been observed in individual(s) with long QT syndrome (Invitae). This variant is present in population databases (rs368011737, gnomAD 0.0009%). This sequence change replaces valine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 215 of the KCNQ1 protein (p.Val215Gly). This variant disrupts the p.Val215 amino acid residue in KCNQ1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 16414944, 19841300, 20421371, 23098067, 23392653). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Beckwith-Wiedemann syndrome;C1837014:Atrial fibrillation, familial, 3;C1865019:Short QT syndrome type 2;C4551509:Jervell and Lange-Nielsen syndrome 1;C4551647:Long QT syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 07, 2024

The p.V215G variant (also known as c.644T>G), located in coding exon 4 of the KCNQ1 gene, results from a T to G substitution at nucleotide position 644. The valine at codon 215 is replaced by glycine, an amino acid with dissimilar properties. Functional analysis suggests this alteration causes a moderate decrease in channel current; however, the physiological relevance of this result is unclear (Vanoye CG et al. Circ Genom Precis Med, 2018 Nov;11:e002345). This alteration has been reported in an ostensibly healthy control (Kapa S et al. Circulation, 2009 Nov;120:1752-60). This variant has also been reported in a sudden unexplained death cohort (Huang J et al. J Forensic Sci, 2015 Mar;60:351-6). This amino acid position is highly conserved in available vertebrate species. 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	0.48
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
Cadd	Pathogenic	26
Dann	Uncertain	1.0
Eigen	Uncertain	0.26
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.93	D;D;D
M_CAP	Pathogenic	0.83	D
MetaRNN	Pathogenic	0.90	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.76	T
PROVEAN	Pathogenic	-5.8	D;D;D
REVEL	Pathogenic	0.88
Sift	Uncertain	0.0020	D;D;D
Sift4G	Uncertain	0.0050	D;D;D
Polyphen		0.64	.;P;.
Vest4		0.68, 0.67
MVP		0.98
MPC		1.3
ClinPred		0.98	D
GERP RS		3.2
Varity_R		0.87
gMVP		0.94

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: rs368011737; hg19: chr11-2592594;