11-2445100-T-C

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000218.3(KCNQ1):c.2T>C(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000032 in 936,200 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 not provided (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000032 (0 hom.)
• Consequence: KCNQ1 NM_000218.3 start_lost
• Clinical Significance: not provided no classification provided O:1
• Conservation: PhyloP100: 0.379

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 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3	c.2T>C	p.Met1?	start_lost	1/16	ENST00000155840.12
KCNQ1	NM_001406836.1	c.2T>C	p.Met1?	start_lost	1/15
KCNQ1	NM_001406838.1	c.2T>C	p.Met1?	start_lost	1/11
KCNQ1	NM_001406837.1	c.-361T>C		5_prime_UTR_variant	1/17

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12	c.2T>C	p.Met1?	start_lost	1/16	1	NM_000218.3	P1
KCNQ1	ENST00000646564.2	c.2T>C	p.Met1?	start_lost	1/11
KCNQ1	ENST00000496887.7	c.24-283T>C		intron_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000320 AC: 3 AN: 936200 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 440548

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000363

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: not provided

Submissions summary: Other:1

Revision: no classification provided

Submissions by phenotype

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 in the following publications (PMID:21380488). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.38
Cadd	Benign	21
Dann	Benign	0.94
DEOGEN2	Benign	0.34	T
Eigen	Benign	-0.58
Eigen_PC	Benign	-0.59
FATHMM_MKL	Benign	0.023	N
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.99	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.92	D
MutationTaster	Benign	1.0	D
PROVEAN	Benign	-0.55	N
REVEL	Uncertain	0.59
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.043	B
Vest4		0.67
MutPred		0.97		Gain of glycosylation at M1 (P = 0.0029);
MVP		0.95
ClinPred		0.38	T
GERP RS		2.1
Varity_R		0.86
gMVP		0.56

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

LitVar

Other links and lift over

dbSNP: rs199473485; hg19: chr11-2466330;