rs370669201

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_005477.3(HCN4):c.2695G>A(p.Val899Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000295 in 1,595,036 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign 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. V899G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: -0.807

Variant links:

Genes affected

HCN4 (HGNC:16882): (hyperpolarization activated cyclic nucleotide gated potassium channel 4) This gene encodes a member of the hyperpolarization-activated cyclic nucleotide-gated potassium channels. The encoded protein shows slow kinetics of activation and inactivation, and is necessary for the cardiac pacemaking process. This channel may also mediate responses to sour stimuli. Mutations in this gene have been linked to sick sinus syndrome 2, also known as atrial fibrillation with bradyarrhythmia or familial sinus bradycardia. Two pseudogenes have been identified on chromosome 15. [provided by RefSeq, Oct 2008]

HCN4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.071670234).

BS2

High AC in GnomAd at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HCN4	NM_005477.3 linkuse as main transcript	c.2695G>A	p.Val899Ile	missense_variant	8/8	ENST00000261917.4
HCN4	XM_011521148.3 linkuse as main transcript	c.1477G>A	p.Val493Ile	missense_variant	7/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HCN4	ENST00000261917.4 linkuse as main transcript	c.2695G>A	p.Val899Ile	missense_variant	8/8	1	NM_005477.3	P1

Frequencies

GnomAD3 genomes

AF:

0.0000724

AC:

AN:

151846

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000145

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000208

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000589

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000240

AC:

AN:

208016

Hom.:

AF XY:

0.0000263

AC XY:

AN XY:

114162

show subpopulations

Gnomad AFR exome

AF:

0.0000840

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000349

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000337

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000249

AC:

AN:

1443074

Hom.:

Cov.:

AF XY:

0.0000265

AC XY:

AN XY:

716420

show subpopulations

Gnomad4 AFR exome

AF:

0.000151

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000257

Gnomad4 SAS exome

AF:

0.0000590

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000217

Gnomad4 OTH exome

AF:

0.0000168

GnomAD4 genome

AF:

0.0000724

AC:

AN:

151962

Hom.:

Cov.:

AF XY:

0.0000942

AC XY:

AN XY:

74278

show subpopulations

Gnomad4 AFR

AF:

0.000145

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000208

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000589

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000100

Hom.:

Bravo

AF:

0.0000642

ESP6500AA

AF:

0.000241

AC:

ESP6500EA

AF:

0.00

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Aug 26, 2020

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 470657; Landrum et al., 2016) -

Brugada syndrome 8

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 20, 2023

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 899 of the HCN4 protein (p.Val899Ile). This variant is present in population databases (rs370669201, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with HCN4-related conditions. ClinVar contains an entry for this variant (Variation ID: 470657). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt HCN4 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 16, 2022

The p.V899I variant (also known as c.2695G>A), located in coding exon 8 of the HCN4 gene, results from a G to A substitution at nucleotide position 2695. The valine at codon 899 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.068

BayesDel_addAF

Benign

-0.42

BayesDel_noAF

Benign

-0.64

Cadd

Benign

0.18

Dann

Benign

0.61

DEOGEN2

Benign

0.19

Eigen

Benign

-1.9

Eigen_PC

Benign

-2.0

FATHMM_MKL

Benign

0.019

LIST_S2

Benign

0.33

M_CAP

Pathogenic

0.39

MetaRNN

Benign

0.072

MetaSVM

Benign

-0.98

MutationAssessor

Benign

0.0

MutationTaster

Benign

1.0

PrimateAI

Pathogenic

0.79

PROVEAN

Benign

-0.25

REVEL

Benign

0.12

Sift

Benign

0.45

Sift4G

Benign

0.44

Polyphen

0.0040

Vest4

0.020

MVP

0.33

MPC

0.14

ClinPred

0.0084

GERP RS

-6.7

Varity_R

0.017

gMVP

0.059

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