NM_020433.5:c.1363C>T

Variant names:

• chr20-44116312-G-A
• rs767514641
• NM_020433.5:c.1363C>T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020433.5(JPH2):​c.1363C>T​(p.Arg455Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000136 in 1,542,886 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: JPH2 NM_020433.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.99

Genes affected

JPH2 (HGNC:14202): (junctophilin 2) Junctional complexes between the plasma membrane and endoplasmic/sarcoplasmic reticulum are a common feature of all excitable cell types and mediate cross talk between cell surface and intracellular ion channels. The protein encoded by this gene is a component of junctional complexes and is composed of a C-terminal hydrophobic segment spanning the endoplasmic/sarcoplasmic reticulum membrane and a remaining cytoplasmic domain that shows specific affinity for the plasma membrane. This gene is a member of the junctophilin gene family. Alternative splicing has been observed at this locus and two variants encoding distinct isoforms are described. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
JPH2	NM_020433.5	c.1363C>T	p.Arg455Trp	missense_variant	Exon 4 of 6	ENST00000372980.4	NP_065166.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
JPH2	ENST00000372980.4	c.1363C>T	p.Arg455Trp	missense_variant	Exon 4 of 6	5	NM_020433.5	ENSP00000362071.3

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152132 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000588

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000122 AC: 17 AN: 1390754 Hom.: 0 Cov.: 34 AF XY: 0.0000131 AC XY: 9 AN XY: 686074

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000254

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000121

Gnomad4 OTH exome AF: 0.0000347

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152132 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74330

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000588

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:1

Aug 08, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 455 of the JPH2 protein (p.Arg455Trp). This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with JPH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 241294). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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

Nov 27, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R455W variant (also known as c.1363C>T), located in coding exon 4 of the JPH2 gene, results from a C to T substitution at nucleotide position 1363. The arginine at codon 455 is replaced by tryptophan, an amino acid with dissimilar properties. This amino acid position is well conserved in available vertebrate species. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.095	T
BayesDel_noAF	Benign	-0.37
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.17	T
Eigen	Benign	-0.16
Eigen_PC	Benign	-0.35
FATHMM_MKL	Benign	0.084	N
LIST_S2	Benign	0.71	T
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.65	D
MetaSVM	Benign	-0.88	T
MutationAssessor	Benign	1.9	L
PrimateAI	Pathogenic	0.88	D
PROVEAN	Benign	-2.0	N
REVEL	Benign	0.13
Sift	Uncertain	0.010	D
Sift4G	Uncertain	0.015	D
Polyphen		1.0	D
Vest4		0.54
MutPred		0.31		Loss of solvent accessibility (P = 0.0199);
MVP		0.74
ClinPred		0.83	D
GERP RS		2.2
Varity_R		0.10
gMVP		0.45

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: rs767514641; hg19: chr20-42744952;