rs199798661

Variant summary

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

The NM_005477.3(HCN4):​c.2978C>T​(p.Thr993Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000069 in 1,594,172 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). Synonymous variant affecting the same amino acid position (i.e. T993T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000065 ( 0 hom. )

Consequence

HCN4
NM_005477.3 missense

Scores

2
1
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:1

Conservation

PhyloP100: 0.911

Publications

2 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=0.07574952).
BP6
Variant 15-73323115-G-A is Benign according to our data. Variant chr15-73323115-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 538076.
BS2
High AC in GnomAd4 at 16 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HCN4NM_005477.3 linkc.2978C>T p.Thr993Met missense_variant Exon 8 of 8 ENST00000261917.4 NP_005468.1 Q9Y3Q4
HCN4XM_011521148.3 linkc.1760C>T p.Thr587Met 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.2978C>T p.Thr993Met missense_variant Exon 8 of 8 1 NM_005477.3 ENSP00000261917.3 Q9Y3Q4

Frequencies

GnomAD3 genomes
AF:
0.000105
AC:
16
AN:
152100
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.000847
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000123
AC:
26
AN:
210654
AF XY:
0.000146
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000322
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00102
Gnomad NFE exome
AF:
0.0000545
Gnomad OTH exome
AF:
0.000196
GnomAD4 exome
AF:
0.0000652
AC:
94
AN:
1441954
Hom.:
0
Cov.:
34
AF XY:
0.0000629
AC XY:
45
AN XY:
715752
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32916
American (AMR)
AF:
0.0000478
AC:
2
AN:
41872
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25060
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39346
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83184
European-Finnish (FIN)
AF:
0.00115
AC:
58
AN:
50496
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5690
European-Non Finnish (NFE)
AF:
0.0000236
AC:
26
AN:
1104010
Other (OTH)
AF:
0.000135
AC:
8
AN:
59380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
7
13
20
26
33
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:
0.000105
AC:
16
AN:
152218
Hom.:
0
Cov.:
33
AF XY:
0.000161
AC XY:
12
AN XY:
74420
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41526
American (AMR)
AF:
0.00
AC:
0
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5142
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.000847
AC:
9
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68002
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
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

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:
0.0000563
Hom.:
0
Bravo
AF:
0.0000151
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000248
AC:
2
ExAC
AF:
0.000151
AC:
18

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1
Apr 05, 2022
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 supports that this missense variant does not alter protein structure/function -

Cardiovascular phenotype Uncertain:1
May 31, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.T993M variant (also known as c.2978C>T), located in coding exon 8 of the HCN4 gene, results from a C to T substitution at nucleotide position 2978. The threonine at codon 993 is replaced by methionine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. 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. -

Brugada syndrome 8 Benign:1
Dec 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.090
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.24
CADD
Benign
18
DANN
Benign
0.97
DEOGEN2
Benign
0.22
T
Eigen
Benign
-0.72
Eigen_PC
Benign
-0.72
FATHMM_MKL
Benign
0.092
N
LIST_S2
Benign
0.65
T
M_CAP
Pathogenic
0.87
D
MetaRNN
Benign
0.076
T
MetaSVM
Uncertain
0.17
D
MutationAssessor
Benign
0.34
N
PhyloP100
0.91
PrimateAI
Pathogenic
0.87
D
PROVEAN
Benign
-0.30
N
REVEL
Benign
0.20
Sift
Benign
0.088
T
Sift4G
Benign
0.15
T
Polyphen
0.037
B
Vest4
0.092
MVP
0.78
MPC
0.18
ClinPred
0.021
T
GERP RS
2.8
Varity_R
0.047
gMVP
0.40
Mutation Taster
=98/2
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: rs199798661; hg19: chr15-73615456; API