7-150950165-T-G

Variant names:

• chr7-150950165-T-G
• rs1554425151
• NM_000238.4:c.2398+3A>C

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM5 PP2 PP3_Moderate

The NM_172056.3(KCNH2):​c.2401A>C​(p.Met801Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M801T) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000040 (0 hom., cov: 28)
  • Exomes 𝑓: 0.00013 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: KCNH2 NM_172056.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.69
• Publications: 1 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.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 12 uncertain in NM_172056.3
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-150950163-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 200446.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in the KCNH2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 158 curated pathogenic missense variants (we use a threshold of 10). The gene has 38 curated benign missense variants. Gene score misZ: 3.3724 (above the threshold of 3.09). Trascript score misZ: 3.4405 (above the threshold of 3.09). GenCC associations: The gene is linked to long QT syndrome 2, short QT syndrome type 1, short QT syndrome, Brugada syndrome, long QT syndrome.
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_172056.3. 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.2398+3A>C		splice_region intron	N/A	NP_000229.1	A0A090N8Q0
	KCNH2	NM_172056.3		c.2401A>C	p.Met801Leu	missense	Exon 9 of 9	NP_742053.1	Q12809-5
	KCNH2	NM_001406755.1		c.2224A>C	p.Met742Leu	missense	Exon 9 of 9	NP_001393684.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.2398+3A>C		splice_region intron	N/A	ENSP00000262186.5	Q12809-1
	KCNH2	ENST00000330883.9	TSL:1	c.1378+3A>C		splice_region intron	N/A	ENSP00000328531.4	Q12809-2
	KCNH2	ENST00000461280.2	TSL:1	n.1699A>C		non_coding_transcript_exon	Exon 5 of 5

Frequencies

GnomAD3 genomes AF: 0.0000400 AC: 5 AN: 124990 Hom.: 0 Cov.: 28

Gnomad AFR AF: 0.0000298

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000266

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000339

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.000130 AC: 79 AN: 609120 Hom.: 0 Cov.: 23 AF XY: 0.000120 AC XY: 39 AN XY: 325108

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

African (AFR) AF: 0.000126 AC: 2 AN: 15864

American (AMR) AF: 0.000103 AC: 4 AN: 38656

Ashkenazi Jewish (ASJ) AF: 0.000126 AC: 2 AN: 15904

East Asian (EAS) AF: 0.000268 AC: 6 AN: 22358

South Asian (SAS) AF: 0.0000142 AC: 1 AN: 70408

European-Finnish (FIN) AF: 0.000266 AC: 10 AN: 37548

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 3584

European-Non Finnish (NFE) AF: 0.000127 AC: 48 AN: 377962

Other (OTH) AF: 0.000224 AC: 6 AN: 26836

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Data not reliable, filtered out with message: AS_VQSR AF: 0.0000400 AC: 5 AN: 125042 Hom.: 0 Cov.: 28 AF XY: 0.0000497 AC XY: 3 AN XY: 60350

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

African (AFR) AF: 0.0000298 AC: 1 AN: 33564

American (AMR) AF: 0.00 AC: 0 AN: 12422

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3078

East Asian (EAS) AF: 0.00 AC: 0 AN: 3502

South Asian (SAS) AF: 0.00 AC: 0 AN: 3032

European-Finnish (FIN) AF: 0.000266 AC: 2 AN: 7530

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 210

European-Non Finnish (NFE) AF: 0.0000339 AC: 2 AN: 59072

Other (OTH) AF: 0.00 AC: 0 AN: 1796

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Benign	-0.074	T
BayesDel_noAF	Benign	-0.34
CADD	Benign	14
DANN	Uncertain	0.98
DEOGEN2	Benign	0.26	T
Eigen	Benign	-0.32
Eigen_PC	Benign	-0.12
FATHMM_MKL	Benign	0.63	D
LIST_S2	Benign	0.68	T
M_CAP	Uncertain	0.087	D
MetaRNN	Benign	0.21	T
MetaSVM	Uncertain	0.13	D
PhyloP100		2.7
REVEL	Uncertain	0.39
Sift4G	Uncertain	0.017	D
Vest4		0.30
MVP		0.26
ClinPred		0.70	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=16/84	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.87		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.87		Position offset: 3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1554425151; hg19: chr7-150647253;