rs773676799

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4BS2

The NM_005477.3(HCN4):​c.581C>T​(p.Ala194Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000749 in 1,601,672 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A194E) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

1
4
14

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.62

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: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.29073948).
BS2
High AC in GnomAdExome4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.581C>T p.Ala194Val missense_variant Exon 1 of 8 ENST00000261917.4 NP_005468.1 Q9Y3Q4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HCN4ENST00000261917.4 linkc.581C>T p.Ala194Val missense_variant Exon 1 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152086
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000861
AC:
2
AN:
232162
AF XY:
0.00000778
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000585
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000552
AC:
8
AN:
1449586
Hom.:
0
Cov.:
32
AF XY:
0.00000277
AC XY:
2
AN XY:
721496
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33456
American (AMR)
AF:
0.0000672
AC:
3
AN:
44662
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26088
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86178
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
42210
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5624
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111536
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60152
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
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

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:
0.0000263
AC:
4
AN:
152086
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41448
American (AMR)
AF:
0.0000655
AC:
1
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67982
Other (OTH)
AF:
0.00
AC:
0
AN:
2080
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
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:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000168
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Brugada syndrome 8 Uncertain:1
Jan 20, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 194 of the HCN4 protein (p.Ala194Val). This variant is present in population databases (rs773676799, gnomAD 0.006%). 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: 578100). 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.083
BayesDel_addAF
Benign
-0.067
T
BayesDel_noAF
Benign
-0.16
CADD
Benign
23
DANN
Uncertain
1.0
DEOGEN2
Benign
0.23
T
Eigen
Benign
-0.27
Eigen_PC
Benign
-0.20
FATHMM_MKL
Uncertain
0.85
D
LIST_S2
Benign
0.70
T
M_CAP
Pathogenic
0.32
D
MetaRNN
Benign
0.29
T
MetaSVM
Uncertain
0.042
D
MutationAssessor
Benign
0.34
N
PhyloP100
1.6
PrimateAI
Uncertain
0.71
T
PROVEAN
Benign
-0.82
N
REVEL
Benign
0.29
Sift
Benign
0.19
T
Sift4G
Benign
0.21
T
Polyphen
0.60
P
Vest4
0.16
MutPred
0.27
Loss of sheet (P = 0.0457);
MVP
0.93
MPC
1.1
ClinPred
0.16
T
GERP RS
1.2
Varity_R
0.073
gMVP
0.27
Mutation Taster
=77/23
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: rs773676799; hg19: chr15-73660031; API