Genetic Variant NM_000218.3:c.671C>T (chr11-2571391-C-T) – ACMG Classification: Pathogenic (16 pts)

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PS3PM1PP2PP3PP5_Very_Strong

The NM_000218.3(KCNQ1):c.671C>T(p.Thr224Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000137 in 1,611,626 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 Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV001390833: Experimental studies have shown that this missense change affects KCNQ1 function (PMID:33141630).; SCV005203435: The variant results in a loss of channel function (Streeten_2020). PMID:32470535, PMID:33141630; SCV001360190: A functional study has shown that this variant causes a significant reduction in total activating and deactivating currents (PMID:33141630).; SCV002102626: Published functional studies showed that p.(T224M) generates significantly less current than wild type channel; additional studies are warranted to validate the functional effect of this variant in vivo (PMID:33141630); SCV003941016: Functional studies suggest this variant may result in a reduction in current; however, these types of studies do not always reflect physiological significance (Streeten, 2020).". Synonymous variant affecting the same amino acid position (i.e. T224T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 5.66

Publications

6 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: G2P, Labcorp Genetics (formerly Invitae)
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

KCNQ1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PS3

PS3 evidence extracted from ClinVar submissions: SCV001390833: Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 33141630).; SCV005203435: The variant results in a loss of channel function (Streeten_2020). PMID:32470535, PMID:33141630; SCV001360190: A functional study has shown that this variant causes a significant reduction in total activating and deactivating currents (PMID: 33141630).; SCV002102626: Published functional studies showed that p.(T224M) generates significantly less current than wild type channel; additional studies are warranted to validate the functional effect of this variant in vivo (PMID: 33141630); SCV003941016: Functional studies suggest this variant may result in a reduction in current; however, these types of studies do not always reflect physiological significance (Streeten, 2020).

PM1

In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 15 uncertain in NM_000218.3

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, Jervell and Lange-Nielsen syndrome 1, long QT syndrome 1, familial atrial fibrillation, short QT syndrome type 2, long QT syndrome, atrial fibrillation, familial, 3, Jervell and Lange-Nielsen syndrome, hypertrophic cardiomyopathy.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.775

PP5

Variant 11-2571391-C-T is Pathogenic according to our data. Variant chr11-2571391-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 67096.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
KCNQ1	NM_000218.3	MANE Select	c.671C>T	p.Thr224Met	missense	Exon 4 of 16	NP_000209.2
KCNQ1	NM_001406836.1		c.671C>T	p.Thr224Met	missense	Exon 4 of 15	NP_001393765.1
KCNQ1	NM_001406837.1		c.401C>T	p.Thr134Met	missense	Exon 5 of 17	NP_001393766.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
KCNQ1	ENST00000155840.12	TSL:1 MANE Select	c.671C>T	p.Thr224Met	missense	Exon 4 of 16	ENSP00000155840.2	P51787-1
KCNQ1	ENST00000335475.6	TSL:1	c.290C>T	p.Thr97Met	missense	Exon 4 of 16	ENSP00000334497.5	P51787-2
KCNQ1	ENST00000910997.1		c.668C>T	p.Thr223Met	missense	Exon 4 of 16	ENSP00000581056.1

Frequencies

GnomAD3 genomes

AF:

0.0000986

AC:

AN:

152124

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.0165

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

GnomAD2 exomes

AF:

0.00000402

AC:

AN:

248566

AF XY:

0.00000741

show subpopulations

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 FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000889

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000480

AC:

AN:

1459502

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

726174

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33478

American (AMR)

AF:

0.00

AC:

AN:

44718

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26132

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86254

European-Finnish (FIN)

AF:

0.00

AC:

AN:

51216

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.00000630

AC:

AN:

1111866

Other (OTH)

AF:

0.00

AC:

AN:

60374

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.475

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.0000986

AC:

AN:

152124

Hom.:

Cov.:

AF XY:

0.0000808

AC XY:

AN XY:

74282

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41432

American (AMR)

AF:

0.00

AC:

AN:

15278

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5172

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10616

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68008

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.492

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.0000869

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

ClinVar submissions

Significance:Pathogenic/Likely pathogenic

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Long QT syndrome (3)

not provided (2)

Cardiac arrhythmia (1)

Cardiovascular phenotype (1)

Congenital long QT syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.44

CardioboostArm

Pathogenic

1.0

BayesDel_addAF

Pathogenic

0.52

BayesDel_noAF

Pathogenic

0.51

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.98

Eigen

Uncertain

0.56

Eigen_PC

Uncertain

0.53

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

1.0

M_CAP

Pathogenic

0.88

MetaRNN

Pathogenic

0.77

MetaSVM

Pathogenic

1.1

MutationAssessor

Benign

1.8

PhyloP100

5.7

PrimateAI

Pathogenic

0.79

PROVEAN

Pathogenic

-5.1

REVEL

Pathogenic

0.95

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.95

MutPred

0.85

Loss of sheet (P = 0.0063)

MVP

0.98

MPC

1.2

ClinPred

0.99

GERP RS

4.3

Varity_R

0.87

gMVP

0.91

Mutation Taster

=5/95

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

Splicevardb

2.0

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over