rs199472764

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1PM2PM5PP2PP3_StrongPP5

The NM_000218.3(KCNQ1):​c.1045T>C​(p.Ser349Pro) 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. 13/23 in silico tools predict a damaging 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. S349W) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)

Consequence

KCNQ1
NM_000218.3 missense

Scores

16
3
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:1O:1

Conservation

PhyloP100: 7.49

Publications

1 publications found
Variant links:
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]
KCNQ1 Gene-Disease associations (from GenCC):
  • long QT syndrome
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • long QT syndrome 1
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • Jervell and Lange-Nielsen syndrome
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • Jervell and Lange-Nielsen syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P
  • atrial fibrillation, familial, 3
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • short QT syndrome
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • short QT syndrome type 2
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • familial atrial fibrillation
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Jervell and Lange-Nielsen syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

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ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PM1
In a hotspot region, there are 19 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 14 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 chr11-2585225-C-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 52942.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 212 curated pathogenic missense variants (we use a threshold of 10). The gene has 12 curated benign missense variants. Gene score misZ: 1.8321 (below the threshold of 3.09). Trascript score misZ: 0.90233 (below the threshold of 3.09). GenCC associations: The gene is linked to short QT syndrome type 2, long QT syndrome 1, Jervell and Lange-Nielsen syndrome 1, long QT syndrome, short QT syndrome, Jervell and Lange-Nielsen syndrome, hypertrophic cardiomyopathy, familial atrial fibrillation, atrial fibrillation, familial, 3.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.989
PP5
Variant 11-2585224-T-C is Pathogenic according to our data. Variant chr11-2585224-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 52941.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ1NM_000218.3 linkc.1045T>C p.Ser349Pro missense_variant Exon 8 of 16 ENST00000155840.12 NP_000209.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNQ1ENST00000155840.12 linkc.1045T>C p.Ser349Pro missense_variant Exon 8 of 16 1 NM_000218.3 ENSP00000155840.2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
Cov.:
31
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Long QT syndrome Pathogenic:1Uncertain:1
May 29, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A different missense substitution at this codon (p.Ser349Trp) has been determined to be pathogenic (PMID: 10973849, 20662986, 22539601). This suggests that the serine residue is critical for KCNQ1 protein function and that other missense substitutions at this position may also be pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has been reported in individuals affected with long QT syndrome (PMID: 16414944). ClinVar contains an entry for this variant (Variation ID: 52941). This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with proline at codon 349 of the KCNQ1 protein (p.Ser349Pro). The serine residue is highly conserved and there is a moderate physicochemical difference between serine and proline. 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. -

Feb 22, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces serine with proline at codon 349 of the KCNQ1 protein. This variant is found within a highly conserved region in C-terminal cytoplasmic domain (a.a. 349-391). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with long QT syndrome (PMID: 16414944). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). A different missense variant occurring at the same codon, p.Ser349Trp, is known to be pathogenic (Clinvar variation ID 52942), indicating that serine at this position is important for KCNQ1 protein function. The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Congenital long QT syndrome Other:1
-
Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

This variant has been reported as associated with Long QT syndrome in the following publications (PMID:16414944). 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
1.0
CardioboostArm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.56
D
BayesDel_noAF
Pathogenic
0.56
CADD
Pathogenic
30
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.99
D;.
Eigen
Pathogenic
0.68
Eigen_PC
Uncertain
0.58
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.97
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
2.9
M;.
PhyloP100
7.5
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-4.7
D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;D
Vest4
0.99
MutPred
0.90
Loss of glycosylation at S349 (P = 0.0259);.;
MVP
0.98
MPC
1.3
ClinPred
1.0
D
GERP RS
3.8
Varity_R
0.99
gMVP
0.99
Mutation Taster
=5/95
disease causing

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

Other links and lift over

dbSNP: rs199472764; hg19: chr11-2606454; API