11-2585280-G-C

Variant names:

• chr11-2585280-G-C
• NM_000218.3:c.1101G>C

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PS1 PM1 PM2 PP3_Strong PP5

The NM_000218.3(KCNQ1):​c.1101G>C​(p.Gln367His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in Lovd.

• Frequency: Genomes: not found (cov: 33)
• Consequence: KCNQ1 NM_000218.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 2.37

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 Pathogenic. Variant got 13 ACMG points.

• PS1: Transcript NM_000218.3 (KCNQ1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM1: In a helix (size 25) in uniprot entity KCNQ1_HUMAN there are 25 pathogenic changes around while only 1 benign (96%) in NM_000218.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.967
• PP5: Variant 11-2585280-G-C is Pathogenic according to our data. Variant chr11-2585280-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1203515.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNQ1	NM_000218.3	c.1101G>C	p.Gln367His	missense_variant	Exon 8 of 16	ENST00000155840.12	NP_000209.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNQ1	ENST00000155840.12	c.1101G>C	p.Gln367His	missense_variant	Exon 8 of 16	1	NM_000218.3	ENSP00000155840.2
KCNQ1	ENST00000335475.6	c.720G>C	p.Gln240His	missense_variant	Exon 8 of 16	1		ENSP00000334497.5
KCNQ1	ENST00000496887.7	c.771+1735G>C		intron_variant	Intron 8 of 15	5		ENSP00000434560.2
KCNQ1	ENST00000646564.2	c.588+1735G>C		intron_variant	Intron 3 of 10			ENSP00000495806.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Long QT syndrome Pathogenic:1

Jan 12, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 367 of the KCNQ1 protein (p.Gln367His). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with long QT syndrome (PMID: 17438609). ClinVar contains an entry for this variant (Variation ID: 1203515). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt KCNQ1 protein function with a positive predictive value of 95%. This variant disrupts the p.Gln367 amino acid residue in KCNQ1. Other variant(s) that disrupt this residue have been determined to be pathogenic (internal data). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided Uncertain:1

Apr 27, 2021

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 23158531) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;.
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M;.
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-4.0	D;D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0070	D;D
Polyphen		1.0	D;D
Vest4		0.87
MutPred		0.80		Loss of MoRF binding (P = 0.0982);.;
MVP		0.98
MPC		1.1
ClinPred		1.0	D
GERP RS		3.8
Varity_R		0.92
gMVP		0.94

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr11-2606510;