rs876657834

Variant names:

• chr20-44186330-C-T
• rs876657834
• NM_020433.5:c.376G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_020433.5(JPH2):​c.376G>A​(p.Gly126Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: JPH2 NM_020433.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.52

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
JPH2	NM_020433.5	c.376G>A	p.Gly126Arg	missense_variant	Exon 1 of 6	ENST00000372980.4	NP_065166.2
JPH2	NM_175913.4	c.376G>A	p.Gly126Arg	missense_variant	Exon 1 of 2		NP_787109.2
JPH2	XM_006723833.5	c.376G>A	p.Gly126Arg	missense_variant	Exon 1 of 2		XP_006723896.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
JPH2	ENST00000372980.4	c.376G>A	p.Gly126Arg	missense_variant	Exon 1 of 6	5	NM_020433.5	ENSP00000362071.3
JPH2	ENST00000342272.3	c.376G>A	p.Gly126Arg	missense_variant	Exon 1 of 2	1		ENSP00000344590.3

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1459216 Hom.: 0 Cov.: 63 AF XY: 0.00 AC XY: 0 AN XY: 725982

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 30

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Dec 10, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Gly126Arg variant in JPH2 has not been previously reported in individuals with cardiomyopathy or in large population studies. Computational prediction too ls and conservation analysis suggest that the p.Gly126Arg variant may impact the protein, though this information is not predictive enough to determine pathogen icity. In summary, the clinical significance of the p.Gly126Arg variant is uncer tain. -

Hypertrophic cardiomyopathy Uncertain:1

Jan 24, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 126 of the JPH2 protein (p.Gly126Arg). This variant is not present in population databases (gnomAD no frequency). 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: 228753). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.69	D;.
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.71	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Uncertain	0.66	D
MutationAssessor	Uncertain	2.4	M;M
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-6.3	D;D
REVEL	Pathogenic	0.89
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;D
Vest4		0.83
MutPred		0.92		Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);
MVP		0.95
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.90
gMVP		0.63

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: rs876657834; hg19: chr20-42814970; COSMIC: COSV60696547;