chr12-32868935-G-C

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2PM5PP3_Strong

The NM_001005242.3(PKP2):​c.1162C>G​(p.Arg388Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,734 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R388Q) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PKP2
NM_001005242.3 missense

Scores

4
8
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.91

Publications

13 publications found
Variant links:
Genes affected
PKP2 (HGNC:9024): (plakophilin 2) This gene encodes a member of the arm-repeat (armadillo) and plakophilin gene families. Plakophilin proteins contain numerous armadillo repeats, localize to cell desmosomes and nuclei, and participate in linking cadherins to intermediate filaments in the cytoskeleton. This gene may regulate the signaling activity of beta-catenin and is required to maintain transcription of genes that control intracellular calcium cycling including ryanodine receptor 2, ankyrin-B, triadin, and calcium channel, voltage-dependent, L type, alpha 1C. Mutations in this gene are associated with different inherited cardiac conditions including Arrythmogenic Cardiomyopathy, Brugada Syndrome, and Idiopathic Ventricular Fibrillation. A processed pseudogene with high similarity to this gene has been mapped to chromosome 12p13. [provided by RefSeq, May 2022]
PKP2 Gene-Disease associations (from GenCC):
  • arrhythmogenic right ventricular cardiomyopathy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • arrhythmogenic right ventricular dysplasia 9
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • left ventricular noncompaction
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Brugada syndrome
    Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp
  • Brugada syndrome 1
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
  • catecholaminergic polymorphic ventricular tachycardia
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
  • dilated cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr12-32868935-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 201979.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.948

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PKP2NM_001005242.3 linkc.1162C>G p.Arg388Gly missense_variant Exon 4 of 13 ENST00000340811.9 NP_001005242.2 Q99959-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PKP2ENST00000340811.9 linkc.1162C>G p.Arg388Gly missense_variant Exon 4 of 13 1 NM_001005242.3 ENSP00000342800.5 Q99959-2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251320
AF XY:
0.00
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460734
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
726700
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33450
American (AMR)
AF:
0.0000224
AC:
1
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86190
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53298
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4976
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111962
Other (OTH)
AF:
0.00
AC:
0
AN:
60304
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 9 Uncertain:1
Oct 01, 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 glycine, which is neutral and non-polar, at codon 388 of the PKP2 protein (p.Arg388Gly). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with PKP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 2564437). 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. This variant disrupts the p.Arg388 amino acid residue in PKP2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19880068, 20152563, 24967631). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Arrhythmogenic right ventricular cardiomyopathy Uncertain:1
Sep 23, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Apr 18, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R388G variant (also known as c.1162C>G), located in coding exon 4 of the PKP2 gene, results from a C to G substitution at nucleotide position 1162. The arginine at codon 388 is replaced by glycine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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
Pathogenic
0.93
BayesDel_addAF
Uncertain
0.062
T
BayesDel_noAF
Uncertain
-0.070
CADD
Uncertain
23
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.51
.;D
Eigen
Benign
-0.029
Eigen_PC
Benign
-0.027
FATHMM_MKL
Benign
0.63
D
LIST_S2
Benign
0.84
T;T
M_CAP
Pathogenic
0.34
D
MetaRNN
Pathogenic
0.95
D;D
MetaSVM
Benign
-0.60
T
MutationAssessor
Benign
1.7
L;L
PhyloP100
2.9
PrimateAI
Uncertain
0.48
T
PROVEAN
Pathogenic
-4.6
D;D
REVEL
Uncertain
0.45
Sift
Uncertain
0.0020
D;D
Sift4G
Uncertain
0.010
D;D
Polyphen
0.27
B;P
Vest4
0.90
MutPred
0.82
Loss of MoRF binding (P = 0.0209);Loss of MoRF binding (P = 0.0209);
MVP
0.79
MPC
0.67
ClinPred
0.98
D
GERP RS
4.0
Varity_R
0.87
gMVP
0.68
Mutation Taster
=31/69
disease causing

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

Other links and lift over

dbSNP: rs766209297; hg19: chr12-33021869; API