chr15-73323398-C-T

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

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. 15/22 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. V899L) 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

2
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: -0.807

Publications

0 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: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.071670234).
BP6
Variant 15-73323398-C-T is Benign according to our data. Variant chr15-73323398-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 470657.
BS2
High AC in GnomAd4 at 11 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005477.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HCN4
NM_005477.3
MANE Select
c.2695G>Ap.Val899Ile
missense
Exon 8 of 8NP_005468.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HCN4
ENST00000261917.4
TSL:1 MANE Select
c.2695G>Ap.Val899Ile
missense
Exon 8 of 8ENSP00000261917.3

Frequencies

GnomAD3 genomes
AF:
0.0000724
AC:
11
AN:
151846
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.0000240
AC:
5
AN:
208016
AF XY:
0.0000263
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000337
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000249
AC:
36
AN:
1443074
Hom.:
0
Cov.:
35
AF XY:
0.0000265
AC XY:
19
AN XY:
716420
show subpopulations
African (AFR)
AF:
0.000151
AC:
5
AN:
33178
American (AMR)
AF:
0.00
AC:
0
AN:
41434
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25808
East Asian (EAS)
AF:
0.0000257
AC:
1
AN:
38876
South Asian (SAS)
AF:
0.0000590
AC:
5
AN:
84774
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49882
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5680
European-Non Finnish (NFE)
AF:
0.0000217
AC:
24
AN:
1103780
Other (OTH)
AF:
0.0000168
AC:
1
AN:
59662
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000724
AC:
11
AN:
151962
Hom.:
0
Cov.:
33
AF XY:
0.0000942
AC XY:
7
AN XY:
74278
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41424
American (AMR)
AF:
0.00
AC:
0
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5120
South Asian (SAS)
AF:
0.000208
AC:
1
AN:
4810
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000589
AC:
4
AN:
67938
Other (OTH)
AF:
0.00
AC:
0
AN:
2104
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.000100
Hom.:
0
Bravo
AF:
0.0000642
ESP6500AA
AF:
0.000241
AC:
1
ESP6500EA
AF:
0.00
AC:
0
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1
Nov 05, 2024
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 indicates that this missense variant does not alter protein structure/function

Brugada syndrome 8 Uncertain:1
Dec 23, 2024
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 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). 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.

HCN4-related disorder Uncertain:1
May 01, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The HCN4 c.2695G>A variant is predicted to result in the amino acid substitution p.Val899Ile. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.015% of alleles in individuals of African descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Cardiovascular phenotype Benign:1
Jan 10, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.068
BayesDel_addAF
Benign
-0.42
T
BayesDel_noAF
Benign
-0.64
CADD
Benign
0.18
DANN
Benign
0.61
DEOGEN2
Benign
0.19
T
Eigen
Benign
-1.9
Eigen_PC
Benign
-2.0
FATHMM_MKL
Benign
0.019
N
LIST_S2
Benign
0.33
T
M_CAP
Pathogenic
0.39
D
MetaRNN
Benign
0.072
T
MetaSVM
Benign
-0.98
T
MutationAssessor
Benign
0.0
N
PhyloP100
-0.81
PrimateAI
Pathogenic
0.79
T
PROVEAN
Benign
-0.25
N
REVEL
Benign
0.12
Sift
Benign
0.45
T
Sift4G
Benign
0.44
T
Polyphen
0.0040
B
Vest4
0.020
MVP
0.33
MPC
0.14
ClinPred
0.0084
T
GERP RS
-6.7
Varity_R
0.017
gMVP
0.059
Mutation Taster
=97/3
polymorphism

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

Other links and lift over

dbSNP: rs370669201; hg19: chr15-73615739; COSMIC: COSV56084243; API