12-32796295-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001005242.3(PKP2):​c.2171A>G​(p.Lys724Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,610,284 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign 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. K724T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000067 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PKP2
NM_001005242.3 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.376

Publications

5 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: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.12200627).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PKP2NM_001005242.3 linkc.2171A>G p.Lys724Arg missense_variant Exon 11 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.2171A>G p.Lys724Arg missense_variant Exon 11 of 13 1 NM_001005242.3 ENSP00000342800.5 Q99959-2

Frequencies

GnomAD3 genomes
AF:
0.00000666
AC:
1
AN:
150176
Hom.:
0
Cov.:
32
show subpopulations
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460108
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
726504
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33428
American (AMR)
AF:
0.00
AC:
0
AN:
44704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26114
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86164
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1110480
Other (OTH)
AF:
0.00
AC:
0
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
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
AF:
0.00000666
AC:
1
AN:
150176
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
73150
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
40470
American (AMR)
AF:
0.00
AC:
0
AN:
15090
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
4892
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4644
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10458
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67862
Other (OTH)
AF:
0.00
AC:
0
AN:
2074
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 9 Uncertain:1
Dec 06, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 768 of the PKP2 protein (p.Lys768Arg). This variant is not present in population databases (gnomAD no frequency). 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: 1789317). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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
Aug 20, 2019
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.K768R variant (also known as c.2303A>G), located in coding exon 12 of the PKP2 gene, results from an A to G substitution at nucleotide position 2303. The lysine at codon 768 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species, and arginine is the reference amino acid in other 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
0.076
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.63
CADD
Benign
14
DANN
Benign
0.97
DEOGEN2
Benign
0.17
.;T
Eigen
Benign
-0.63
Eigen_PC
Benign
-0.46
FATHMM_MKL
Benign
0.38
N
LIST_S2
Benign
0.77
T;T
M_CAP
Benign
0.0046
T
MetaRNN
Benign
0.12
T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
0.28
.;N
PhyloP100
0.38
PrimateAI
Benign
0.42
T
PROVEAN
Benign
-0.76
N;N
REVEL
Benign
0.065
Sift
Benign
0.57
T;T
Sift4G
Benign
0.97
T;T
Polyphen
0.0
B;B
Vest4
0.27
MutPred
0.29
.;Loss of ubiquitination at K768 (P = 0.0161);
MVP
0.57
MPC
0.13
ClinPred
0.19
T
GERP RS
0.10
Varity_R
0.042
gMVP
0.14
Mutation Taster
=71/29
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs201487421; hg19: chr12-32949229; API