rs199472694
Variant summary
Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BS3_SupportingBS1BS4
This summary comes from the ClinGen Evidence Repository: NM_000218.3(KCNQ1):c.514G>A is a missense variant that substitutes valine with methionine at codon 172 (p.Val172Met). This variant is present in gnomAD v.4.1.0 at a maximum allele frequency of 0.0001317, with 12 alleles / 91,084 total alleles in the South Asian population, which is higher than the ClinGen Potassium Channel Arrhythmia VCEP BS1 threshold of >0.0001 (BS1). At least two patients affected with long QT syndrome have been identified with the p.Val172Met and p.Arg293Cys variants in cis, in the homozygous state (PMID:28944242, PMID:28438721). However, PM3 is not met because the variant is not sufficiently rare. The variant has been observed in a family with long QT syndrome but fails to segregate with the disease phenotype in at least 2 affected members (PMID:28438721; BS4). This variant has been observed in at least 2 probands with a possible alternate molecular basis for disease, however, the alternative variants are located within KCNQ1 itself and the phenotype does not match another form of LQTS, so this evidence is not considered eligible for the BP5 code (PMID:28944242, PMID:28438721). Exogenously expressed KCNQ1 harboring this variant has an IKs of 1.117 (expressed as a fraction of the wild-type), which indicates higher-than-wild-type activity within the near-normal range (PMID:30571187). The Meiler Lab functional impact predictor gave this variant a classification of normal for IKs, V1/2_classification, Tau of activation, and Tau of deactviation, consistent with benign impact on the protein product (PMID:29021305, BS3_Moderate). In summary, this variant meets the criteria to be classified as benign for long QT syndrome 1 based on the ACMG/AMP criteria applied, as specified by the ClinGen Potassium Channel Arrhythmia VCEP: BS1, BS4, and BS3_Moderate. (VCEP specifications version 1.0.0; date of approval 03/04/2025). LINK:https://erepo.genome.network/evrepo/ui/classification/CA007311/MONDO:0100316/112
Frequency
Consequence
NM_000218.3 missense
Scores
Clinical Significance
Conservation
Publications
- long QT syndromeInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- long QT syndrome 1Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
- Jervell and Lange-Nielsen syndromeInheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
- Jervell and Lange-Nielsen syndrome 1Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
- atrial fibrillation, familial, 3Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
- short QT syndromeInheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet
- short QT syndrome type 2Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
- familial atrial fibrillationInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Jervell and Lange-Nielsen syndromeInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- hypertrophic cardiomyopathyInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
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ACMG classification
Our verdict: Benign. The variant received -9 ACMG points.
Variant Effect in Transcripts
ACMG analysis was done for transcript: NM_000218.3. You can select a different transcript below to see updated ACMG assignments.
RefSeq Transcripts
Ensembl Transcripts
| Sel. | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| KCNQ1 | TSL:1 MANE Select | c.514G>A | p.Val172Met | missense | Exon 3 of 16 | ENSP00000155840.2 | P51787-1 | ||
| KCNQ1 | TSL:1 | c.133G>A | p.Val45Met | missense | Exon 3 of 16 | ENSP00000334497.5 | P51787-2 | ||
| KCNQ1 | c.511G>A | p.Val171Met | missense | Exon 3 of 16 | ENSP00000581056.1 |
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152196Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000521 AC: 13AN: 249562 AF XY: 0.0000739 show subpopulations
GnomAD4 exome AF: 0.0000336 AC: 49AN: 1460330Hom.: 0 Cov.: 32 AF XY: 0.0000509 AC XY: 37AN XY: 726558 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152196Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1AN XY: 74350 show subpopulations
Age Distribution
ClinVar
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at