rs768734319

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BS2

The NM_005477.3(HCN4):​c.597G>T​(p.Gln199His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000015 in 1,604,428 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q199K) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

3
6
10

Clinical Significance

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

Conservation

PhyloP100: 1.07

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 -4 ACMG points.

BS2
High AC in GnomAd4 at 9 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.597G>T p.Gln199His 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.597G>T p.Gln199His missense_variant Exon 1 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
AF:
0.0000592
AC:
9
AN:
152112
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000193
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000129
AC:
3
AN:
232552
AF XY:
0.0000155
show subpopulations
Gnomad AFR exome
AF:
0.000148
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:
0.00000946
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1452316
Hom.:
0
Cov.:
32
AF XY:
0.00000830
AC XY:
6
AN XY:
722790
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33464
American (AMR)
AF:
0.00
AC:
0
AN:
44672
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86212
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
44996
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5696
European-Non Finnish (NFE)
AF:
0.0000108
AC:
12
AN:
1111390
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60104
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.518
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.0000592
AC:
9
AN:
152112
Hom.:
0
Cov.:
32
AF XY:
0.0000942
AC XY:
7
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.000193
AC:
8
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15288
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:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67988
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
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:
0.00
Hom.:
0
Bravo
AF:
0.0000378
ExAC
AF:
0.0000169
AC:
2

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
Oct 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 199 of the HCN4 protein (p.Gln199His). This variant is present in population databases (rs768734319, gnomAD 0.02%). 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: 538075). 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
Oct 06, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Q199H variant (also known as c.597G>T), located in coding exon 1 of the HCN4 gene, results from a G to T substitution at nucleotide position 597. The glutamine at codon 199 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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
0.21
BayesDel_addAF
Benign
-0.079
T
BayesDel_noAF
Benign
-0.10
CADD
Benign
17
DANN
Uncertain
0.98
DEOGEN2
Benign
0.38
T
Eigen
Benign
0.0082
Eigen_PC
Benign
-0.036
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.43
T
M_CAP
Pathogenic
0.54
D
MetaRNN
Uncertain
0.60
D
MetaSVM
Pathogenic
0.81
D
MutationAssessor
Benign
1.8
L
PhyloP100
1.1
PrimateAI
Pathogenic
0.79
T
PROVEAN
Benign
-1.5
N
REVEL
Uncertain
0.52
Sift
Uncertain
0.027
D
Sift4G
Uncertain
0.0060
D
Polyphen
0.98
D
Vest4
0.39
MutPred
0.26
Loss of loop (P = 0.0374);
MVP
0.96
MPC
1.0
ClinPred
0.17
T
GERP RS
2.3
Varity_R
0.088
gMVP
0.65
Mutation Taster
=84/16
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: rs768734319; hg19: chr15-73660015; API