rs199472844

Variant names:

• chr7-150974854-G-A
• rs199472844
• NM_000238.4:c.164C>T

Your query was ambiguous. Multiple possible variants found:

• chr7-150974854-G-A
• chr7-150974854-G-C
• chr7-150974854-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PP3_Strong PP5

The NM_001406755.1(KCNH2):​c.-14C>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,458,400 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: KCNH2 NM_001406755.1 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1 O:1
• Conservation: PhyloP100: 7.97
• Publications: 10 publications found

Genes affected

KCNH2 (HGNC:6251): (potassium voltage-gated channel subfamily H member 2) This gene encodes a component of a voltage-activated potassium channel found in cardiac muscle, nerve cells, and microglia. Four copies of this protein interact with one copy of the KCNE2 protein to form a functional potassium channel. Mutations in this gene can cause long QT syndrome type 2 (LQT2). Transcript variants encoding distinct isoforms have been identified. [provided by RefSeq, May 2022]

KCNH2 Gene-Disease associations (from GenCC):

• long QT syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• long QT syndrome 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• short QT syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• short QT syndrome type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• Brugada syndrome

  Inheritance: AD Classification: MODERATE, NO_KNOWN Submitted by: ClinGen, Genomics England PanelApp

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.971
• PP5: Variant 7-150974854-G-A is Pathogenic according to our data. Variant chr7-150974854-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 67224.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001406755.1. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	NM_000238.4	MANE Select	c.164C>T	p.Ser55Leu	missense	Exon 2 of 15	NP_000229.1	A0A090N8Q0
	KCNH2	NM_001406755.1		c.-14C>T		5_prime_UTR_premature_start_codon_gain	Exon 2 of 9	NP_001393684.1
	KCNH2	NM_172056.3		c.164C>T	p.Ser55Leu	missense	Exon 2 of 9	NP_742053.1	Q12809-5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.164C>T	p.Ser55Leu	missense	Exon 2 of 15	ENSP00000262186.5	Q12809-1
	KCNH2	ENST00000713710.1		c.164C>T	p.Ser55Leu	missense	Exon 2 of 15	ENSP00000519013.1	A0AAQ5BGR0
	KCNH2	ENST00000945647.1		c.164C>T	p.Ser55Leu	missense	Exon 2 of 14	ENSP00000615706.1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1458400 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 725420

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33378

American (AMR) AF: 0.00 AC: 0 AN: 44506

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26052

East Asian (EAS) AF: 0.00 AC: 0 AN: 39574

South Asian (SAS) AF: 0.00 AC: 0 AN: 85974

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52246

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5654

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1110836

Other (OTH) AF: 0.00 AC: 0 AN: 60180

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 34

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	-	-	Cardiovascular phenotype (1)
-	1	-	Long QT syndrome (1)
1	-	-	Long QT syndrome 2 (1)
1	-	-	not provided (1)
-	-	-	Congenital long QT syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.59
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.1	M
PhyloP100		8.0
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.5	D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		0.38	B
Vest4		0.89
MutPred		0.80		Loss of catalytic residue at S55 (P = 0.0055)
MVP		1.0
MPC		1.5
ClinPred		1.0	D
GERP RS		4.4
Varity_R		0.87
gMVP		0.96
Mutation Taster		=23/77	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs199472844; hg19: chr7-150671942;