rs376631391

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_005477.3(HCN4):​c.2197G>A​(p.Val733Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000929 in 1,603,796 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V733A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000098 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

6
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:1

Conservation

PhyloP100: 3.10

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • sick sinus syndrome 2, autosomal dominant
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • Brugada syndrome 8
    Inheritance: AD Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • familial sick sinus syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • Brugada syndrome 1
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.2265509).
BS2
High AC in GnomAd4 at 7 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.2197G>A p.Val733Ile missense_variant Exon 8 of 8 ENST00000261917.4 NP_005468.1 Q9Y3Q4
HCN4XM_011521148.3 linkc.979G>A p.Val327Ile missense_variant Exon 7 of 7 XP_011519450.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HCN4ENST00000261917.4 linkc.2197G>A p.Val733Ile missense_variant Exon 8 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152198
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000588
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000787
AC:
19
AN:
241316
AF XY:
0.0000913
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000868
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000144
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000978
AC:
142
AN:
1451480
Hom.:
0
Cov.:
35
AF XY:
0.000104
AC XY:
75
AN XY:
722498
show subpopulations
African (AFR)
AF:
0.000119
AC:
4
AN:
33476
American (AMR)
AF:
0.0000895
AC:
4
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
43174
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000112
AC:
124
AN:
1111928
Other (OTH)
AF:
0.000133
AC:
8
AN:
60330
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.476
Heterozygous variant carriers
0
11
22
32
43
54
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152316
Hom.:
0
Cov.:
33
AF XY:
0.0000671
AC XY:
5
AN XY:
74490
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41566
American (AMR)
AF:
0.00
AC:
0
AN:
15312
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68014
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.454
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000120
Hom.:
0
Bravo
AF:
0.0000756
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.00
EpiControl
AF:
0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Jul 20, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 30, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis supports that this missense variant does not alter protein structure/function -

Cardiac arrest Uncertain:1
Nov 16, 2015
Blueprint Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sick sinus syndrome 2, autosomal dominant;C2751083:Brugada syndrome 8;C5561983:Epilepsy, idiopathic generalized, susceptibility to, 18 Uncertain:1
Aug 25, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Brugada syndrome 8 Uncertain:1
Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 733 of the HCN4 protein (p.Val733Ile). This variant is present in population databases (rs376631391, 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: 222648). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) 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
Nov 02, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V733I variant (also known as c.2197G>A), located in coding exon 8 of the HCN4 gene, results from a G to A substitution at nucleotide position 2197. The valine at codon 733 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is conserved. 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. -

not specified Benign:1
Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BS1, BP4, BP5 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.17
T
BayesDel_noAF
Benign
-0.27
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Benign
0.24
T
Eigen
Benign
0.068
Eigen_PC
Benign
0.074
FATHMM_MKL
Uncertain
0.78
D
LIST_S2
Uncertain
0.87
D
M_CAP
Benign
0.069
D
MetaRNN
Benign
0.23
T
MetaSVM
Uncertain
-0.21
T
MutationAssessor
Benign
2.0
M
PhyloP100
3.1
PrimateAI
Uncertain
0.54
T
PROVEAN
Benign
-0.59
N
REVEL
Benign
0.29
Sift
Benign
0.042
D
Sift4G
Uncertain
0.059
T
Polyphen
0.96
D
Vest4
0.26
MVP
0.85
MPC
0.14
ClinPred
0.050
T
GERP RS
3.5
Varity_R
0.090
gMVP
0.69
Mutation Taster
=88/12
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs376631391; hg19: chr15-73616237; API