1-155282563-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_020897.3(HCN3):c.431A>G(p.Asn144Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,894 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: HCN3 NM_020897.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32

Genes affected

HCN3 (HGNC:19183): (hyperpolarization activated cyclic nucleotide gated potassium channel 3) This gene encodes a multi-pass membrane protein that functions as a voltage gated cation channel. The encoded protein is a member of a family of closely related cyclic adenosine monophosphate-binding channel proteins. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.887

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HCN3	NM_020897.3	c.431A>G	p.Asn144Ser	missense_variant	2/8	ENST00000368358.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HCN3	ENST00000368358.4	c.431A>G	p.Asn144Ser	missense_variant	2/8	1	NM_020897.3	P1
HCN3	ENST00000467204.1	n.26A>G		non_coding_transcript_exon_variant	1/5	5
HCN3	ENST00000496230.5	n.323A>G		non_coding_transcript_exon_variant	2/8	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251474 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135912

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

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: 0.00000205 AC: 3 AN: 1461894 Hom.: 0 Cov.: 36 AF XY: 0.00000413 AC XY: 3 AN XY: 727248

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 14, 2023

The c.431A>G (p.N144S) alteration is located in exon 2 (coding exon 2) of the HCN3 gene. This alteration results from a A to G substitution at nucleotide position 431, causing the asparagine (N) at amino acid position 144 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	0.060
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.75	D
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Uncertain	0.16	D
MetaRNN	Pathogenic	0.89	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.5	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-4.7	D
REVEL	Pathogenic	0.91
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.048	D
Polyphen		0.99	D
Vest4		0.95
MutPred		0.54		Loss of stability (P = 0.1031);
MVP		0.99
MPC		1.2
ClinPred		0.99	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.63
gMVP		0.88

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1172005432; hg19: chr1-155252354;