15-73367674-C-G

Variant names:

• chr15-73367674-C-G
• rs768734319
• NM_005477.3:c.597G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_005477.3(HCN4):​c.597G>C​(p.Gln199His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,452,318 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: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HCN4 NM_005477.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.07
• Publications: 1 publications found

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: DEFINITIVE, STRONG Submitted by: ClinGen, Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Brugada syndrome 8

  Inheritance: AD Classification: MODERATE, LIMITED Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• familial sick sinus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Brugada syndrome 1

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005477.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HCN4	NM_005477.3	MANE Select	c.597G>C	p.Gln199His	missense	Exon 1 of 8	NP_005468.1	Q9Y3Q4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HCN4	ENST00000261917.4	TSL:1 MANE Select	c.597G>C	p.Gln199His	missense	Exon 1 of 8	ENSP00000261917.3	Q9Y3Q4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000430 AC: 1 AN: 232552 AF XY: 0.00000775

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000568

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1452318 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 722792

African (AFR) AF: 0.00 AC: 0 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: 0.00 AC: 0 AN: 1111392

Other (OTH) AF: 0.0000166 AC: 1 AN: 60104

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000113

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Cardiovascular phenotype (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Benign	-0.021	T
BayesDel_noAF	Benign	-0.10
CADD	Benign	17
DANN	Uncertain	0.99
DEOGEN2	Benign	0.38	T
Eigen	Benign	0.0082
Eigen_PC	Benign	-0.036
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Benign	0.43	T
M_CAP	Pathogenic	0.54	D
MetaRNN	Uncertain	0.56	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		0.43	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

Other links and lift over

dbSNP: rs768734319; hg19: chr15-73660015;