rs998387579

Positions:

• chr15-73329715-C-T

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 2P and 7B. PM1 BP4_Moderate BP6 BS2

The NM_005477.3(HCN4):​c.1448G>A​(p.Arg483Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,614,044 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R483W) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 34)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: HCN4 NM_005477.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 3.47

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]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 9 uncertain in NM_005477.3
• BP4: Computational evidence support a benign effect (MetaRNN=0.2178742).
• BP6: Variant 15-73329715-C-T is Benign according to our data. Variant chr15-73329715-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 470648.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.
• BS2: High AC in GnomAdExome4 at 21 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HCN4	NM_005477.3	c.1448G>A	p.Arg483Gln	missense_variant	4/8	ENST00000261917.4
HCN4	XM_011521148.3	c.230G>A	p.Arg77Gln	missense_variant	3/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HCN4	ENST00000261917.4	c.1448G>A	p.Arg483Gln	missense_variant	4/8	1	NM_005477.3	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152220 Hom.: 0 Cov.: 34

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000578

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

GnomAD3 exomes AF: 0.0000279 AC: 7 AN: 251328 Hom.: 0 AF XY: 0.0000368 AC XY: 5 AN XY: 135866

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000381

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000144 AC: 21 AN: 1461824 Hom.: 0 Cov.: 32 AF XY: 0.0000179 AC XY: 13 AN XY: 727212

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000302

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000719

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152220 Hom.: 0 Cov.: 34 AF XY: 0.0000269 AC XY: 2 AN XY: 74372

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000578

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000491

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 02, 2022

The p.R483Q variant (also known as c.1448G>A), located in coding exon 4 of the HCN4 gene, results from a G to A substitution at nucleotide position 1448. The arginine at codon 483 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Brugada syndrome 8 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.085
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.20
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.73	D
Eigen	Benign	-0.48
Eigen_PC	Benign	-0.36
FATHMM_MKL	Benign	0.66	D
LIST_S2	Uncertain	0.91	D
M_CAP	Uncertain	0.096	D
MetaRNN	Benign	0.22	T
MetaSVM	Uncertain	-0.028	T
MutationAssessor	Benign	0.81	L
MutationTaster	Benign	0.98	D
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-1.2	N
REVEL	Uncertain	0.31
Sift	Benign	0.47	T
Sift4G	Benign	0.31	T
Polyphen		0.0010	B
Vest4		0.20
MutPred		0.53		Loss of sheet (P = 0.302);
MVP		0.86
MPC		1.2
ClinPred		0.092	T
GERP RS		1.8
Varity_R		0.14
gMVP		0.73

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

LitVar

Other links and lift over

dbSNP: rs998387579; hg19: chr15-73622056; COSMIC: COSV56086816;