chr20-44116020-G-A

Position:

• chr20-44116020-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_020433.5(JPH2):​c.1655C>T​(p.Pro552Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000007 in 1,428,790 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: JPH2 NM_020433.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.04

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3030964).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
JPH2	NM_020433.5	c.1655C>T	p.Pro552Leu	missense_variant	4/6	ENST00000372980.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
JPH2	ENST00000372980.4	c.1655C>T	p.Pro552Leu	missense_variant	4/6	5	NM_020433.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.00e-7 AC: 1 AN: 1428790 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 709790

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: 9.06e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jan 26, 2016

The p.Pro552Leu variant in JPH2 has not been previously reported in individuals with cardiomyopathy and data from large population studies is insufficient to as sess the frequency of this variant. Computational prediction tools and conservat ion analysis do not provide strong support for or against an impact to the prote in. In summary, the clinical significance of the p.Pro552Leu variant is uncertai n. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Dec 24, 2019

Has not been previously published as pathogenic or benign to our knowledge; Reported in ClinVar as a variant of uncertain significance by another clinical laboratory (ClinVar Variant ID# 228752; Landrum et al., 2016); Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 23, 2022

The p.P552L variant (also known as c.1655C>T), located in coding exon 4 of the JPH2 gene, results from a C to T substitution at nucleotide position 1655. The proline at codon 552 is replaced by leucine, an amino acid with 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.093
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.45
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Benign	0.17	T
Eigen	Benign	-0.17
Eigen_PC	Benign	-0.24
FATHMM_MKL	Benign	0.22	N
LIST_S2	Benign	0.54	T
M_CAP	Uncertain	0.28	D
MetaRNN	Benign	0.30	T
MetaSVM	Benign	-0.91	T
MutationAssessor	Benign	1.7	L
MutationTaster	Benign	0.98	D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-0.95	N
REVEL	Benign	0.095
Sift	Benign	0.18	T
Sift4G	Benign	0.14	T
Polyphen		0.90	P
Vest4		0.32
MutPred		0.22		Loss of glycosylation at P552 (P = 0.0081);
MVP		0.82
ClinPred		0.36	T
GERP RS		2.9
Varity_R		0.076
gMVP		0.33

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: rs876657833; hg19: chr20-42744660;