rs199473412

Positions:

• chr11-2585290-G-A
• chr11-2585290-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000218.3(KCNQ1):​c.1111G>A​(p.Ala371Thr) variant causes a missense change involving the alteration of a 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 not provided (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: KCNQ1 NM_000218.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 9.33

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 8 ACMG points.

• 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, 0.973

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNQ1	NM_000218.3	c.1111G>A	p.Ala371Thr	missense_variant	8/16	ENST00000155840.12	NP_000209.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNQ1	ENST00000155840.12	c.1111G>A	p.Ala371Thr	missense_variant	8/16	1	NM_000218.3	ENSP00000155840.2
KCNQ1	ENST00000335475.6	c.730G>A	p.Ala244Thr	missense_variant	8/16	1		ENSP00000334497.5
KCNQ1	ENST00000496887.7	c.771+1745G>A		intron_variant		5		ENSP00000434560.2
KCNQ1	ENST00000646564.2	c.588+1745G>A		intron_variant				ENSP00000495806.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cardiovascular phenotype Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 24, 2024

The p.A371T variant (also known as c.1111G>A), located in coding exon 8 of the KCNQ1 gene, results from a G to A substitution at nucleotide position 1111. The alanine at codon 371 is replaced by threonine, an amino acid with similar properties. This variant was reported in individuals with features consistent with long QT syndrome (Donger C et al. Circulation, 1997 Nov;96:2778-81; Mazzadi AN et al. Am J Physiol Heart Circ Physiol, 2003 Sep;285:H1286-93; Ambry internal data). Functional studies suggest this variant may impair channel function; however, additional evidence is needed to confirm this finding (Shamgar L et al. Circ Res, 2006 Apr;98:1055-63). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Congenital long QT syndrome Other:1

not provided, no classification provided

literature only

Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust

-

This variant has been reported as associated with Long QT syndrome in the following publications (PMID:9386136). This is a literature report, and does not necessarily reflect the clinical interpretation of the Imperial College / Royal Brompton Cardiovascular Genetics laboratory. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.94	D;.
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.96	D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	2.9	M;.
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-3.8	D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.81
MutPred		0.80		Loss of MoRF binding (P = 0.1284);.;
MVP		0.98
MPC		1.1
ClinPred		1.0	D
GERP RS		3.8
Varity_R		0.90
gMVP		0.98

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

LitVar

Other links and lift over

dbSNP: rs199473412; hg19: chr11-2606520;