rs777648103

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_005477.3(HCN4):​c.2830G>T​(p.Ala944Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000218 in 1,373,074 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A944T) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

1
2
16

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.36

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: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.13132012).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.2830G>T p.Ala944Ser missense_variant Exon 8 of 8 ENST00000261917.4 NP_005468.1 Q9Y3Q4
HCN4XM_011521148.3 linkc.1612G>T p.Ala538Ser 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.2830G>T p.Ala944Ser missense_variant Exon 8 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.0000144
AC:
2
AN:
139332
AF XY:
0.0000269
show subpopulations
Gnomad AFR exome
AF:
0.00
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:
0.0000342
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000218
AC:
3
AN:
1373074
Hom.:
0
Cov.:
34
AF XY:
0.00000297
AC XY:
2
AN XY:
672678
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31924
American (AMR)
AF:
0.00
AC:
0
AN:
33024
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
22126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
37940
South Asian (SAS)
AF:
0.00
AC:
0
AN:
73350
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
44926
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5204
European-Non Finnish (NFE)
AF:
0.00000281
AC:
3
AN:
1067792
Other (OTH)
AF:
0.00
AC:
0
AN:
56788
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.558
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33
ExAC
AF:
0.00000869
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Brugada syndrome 8 Uncertain:1
May 05, 2022
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 serine, which is neutral and polar, at codon 944 of the HCN4 protein (p.Ala944Ser). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. 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. 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. This variant has not been reported in the literature in individuals affected with HCN4-related conditions. -

Cardiovascular phenotype Uncertain:1
Apr 04, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A944S variant (also known as c.2830G>T), located in coding exon 8 of the HCN4 gene, results from a G to T substitution at nucleotide position 2830. The alanine at codon 944 is replaced by serine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.069
BayesDel_addAF
Benign
-0.11
T
BayesDel_noAF
Benign
-0.29
CADD
Benign
5.7
DANN
Benign
0.44
DEOGEN2
Benign
0.21
T
Eigen
Benign
-1.2
Eigen_PC
Benign
-1.3
FATHMM_MKL
Benign
0.035
N
LIST_S2
Benign
0.37
T
M_CAP
Pathogenic
0.70
D
MetaRNN
Benign
0.13
T
MetaSVM
Uncertain
-0.19
T
MutationAssessor
Benign
0.20
N
PhyloP100
1.4
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
-0.070
N
REVEL
Benign
0.19
Sift
Benign
0.47
T
Sift4G
Benign
0.63
T
Polyphen
0.011
B
Vest4
0.075
MutPred
0.18
Gain of phosphorylation at A944 (P = 0.0041);
MVP
0.59
MPC
0.16
ClinPred
0.0085
T
GERP RS
0.99
Varity_R
0.029
gMVP
0.15
Mutation Taster
=94/6
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: rs777648103; hg19: chr15-73615604; API