Genetic Variant KCNH8:p.Arg164Trp (chr3-19342634-C-T) – ACMG Classification: Uncertain_significance (3 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_144633.3(KCNH8):c.490C>T(p.Arg164Trp) variant causes a missense change. The variant allele was found at a frequency of 0.0000168 in 1,610,730 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R164Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

KCNH8
NM_144633.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.81

Variant links:

Genes affected

KCNH8 (HGNC:18864): (potassium voltage-gated channel subfamily H member 8) Voltage-gated potassium (Kv) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a member of the potassium channel, voltage-gated, subfamily H. This member is a pore-forming (alpha) subunit. [provided by RefSeq, Jul 2008]

KCNH8 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.819

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNH8	NM_144633.3 link	c.490C>T	p.Arg164Trp	missense_variant	Exon 4 of 16	ENST00000328405.7	NP_653234.2	Q96L42-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNH8	ENST00000328405.7 link	c.490C>T	p.Arg164Trp	missense_variant	Exon 4 of 16	1	NM_144633.3	ENSP00000328813.2		Q96L42-1
KCNH8	ENST00000452398.5 link	n.490C>T		non_coding_transcript_exon_variant	Exon 4 of 16	1		ENSP00000412141.1		F8WCG6

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152036

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.000479

GnomAD3 exomes

AF:

0.0000240

AC:

AN:

250166

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

135204

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000266

Gnomad OTH exome

AF:

0.000328

GnomAD4 exome

AF:

0.0000165

AC:

AN:

1458694

Hom.:

Cov.:

AF XY:

0.0000193

AC XY:

AN XY:

725752

show subpopulations

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:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000198

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152036

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74258

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.000479

Bravo

AF:

0.0000227

ExAC

AF:

0.0000330

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000178

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Sep 17, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.490C>T (p.R164W) alteration is located in exon 4 (coding exon 4) of the KCNH8 gene. This alteration results from a C to T substitution at nucleotide position 490, causing the arginine (R) at amino acid position 164 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.85

BayesDel_addAF

Pathogenic

0.32

BayesDel_noAF

Pathogenic

0.41

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.60

Eigen

Uncertain

0.62

Eigen_PC

Uncertain

0.59

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.99

M_CAP

Uncertain

0.19

MetaRNN

Pathogenic

0.82

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.6

PrimateAI

Uncertain

0.79

PROVEAN

Pathogenic

-6.7

REVEL

Pathogenic

0.74

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.78

MutPred

0.44

Loss of disorder (P = 0.0019);

MVP

0.97

MPC

0.29

ClinPred

0.85

GERP RS

4.9

Varity_R

0.59

gMVP

0.73

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over