rs982016034

Variant summary

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

The NM_005477.3(HCN4):​c.3218C>T​(p.Pro1073Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000203 in 1,475,900 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. P1073R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

2
5
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 3.11

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=0.29060838).
BS2
High AC in GnomAdExome4 at 27 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.3218C>T p.Pro1073Leu missense_variant Exon 8 of 8 ENST00000261917.4 NP_005468.1 Q9Y3Q4
HCN4XM_011521148.3 linkc.2000C>T p.Pro667Leu 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.3218C>T p.Pro1073Leu missense_variant Exon 8 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152090
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000207
AC:
2
AN:
96392
AF XY:
0.0000200
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000861
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000232
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000204
AC:
27
AN:
1323810
Hom.:
0
Cov.:
35
AF XY:
0.0000186
AC XY:
12
AN XY:
644806
show subpopulations
African (AFR)
AF:
0.0000331
AC:
1
AN:
30242
American (AMR)
AF:
0.00
AC:
0
AN:
23844
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
19402
East Asian (EAS)
AF:
0.0000529
AC:
2
AN:
37782
South Asian (SAS)
AF:
0.0000608
AC:
4
AN:
65766
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
38260
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5116
European-Non Finnish (NFE)
AF:
0.0000172
AC:
18
AN:
1048532
Other (OTH)
AF:
0.0000365
AC:
2
AN:
54866
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.532
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000197
AC:
3
AN:
152090
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74302
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41416
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5158
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000000000000888178), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.392
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:
0.0000227
ExAC
AF:
0.0000185
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Dec 12, 2023
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; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function -

Sick sinus syndrome 2, autosomal dominant Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Brugada syndrome 8 Uncertain:1
Jun 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 1073 of the HCN4 protein (p.Pro1073Leu). 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. 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: 538077). 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 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
Apr 18, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.P1073L variant (also known as c.3218C>T), located in coding exon 8 of the HCN4 gene, results from a C to T substitution at nucleotide position 3218. The proline at codon 1073 is replaced by leucine, an amino acid with similar properties. This amino acid position is well 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
0.093
BayesDel_addAF
Uncertain
0.065
T
BayesDel_noAF
Benign
-0.15
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.34
T
Eigen
Benign
-0.37
Eigen_PC
Benign
-0.30
FATHMM_MKL
Benign
0.75
D
LIST_S2
Benign
0.58
T
M_CAP
Pathogenic
0.86
D
MetaRNN
Benign
0.29
T
MetaSVM
Uncertain
0.33
D
MutationAssessor
Benign
1.0
L
PhyloP100
3.1
PrimateAI
Pathogenic
0.88
D
PROVEAN
Benign
-0.84
N
REVEL
Benign
0.27
Sift
Uncertain
0.0020
D
Sift4G
Uncertain
0.013
D
Polyphen
0.013
B
Vest4
0.31
MVP
0.85
MPC
0.71
ClinPred
0.60
D
GERP RS
2.8
Varity_R
0.060
gMVP
0.37
Mutation Taster
=81/19
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: rs982016034; hg19: chr15-73615216; API