chr12-32877906-G-A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM1BP4_ModerateBS2_Supporting

The NM_001005242.3(PKP2):​c.974C>T​(p.Ala325Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000458 in 1,614,028 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. A325G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000046 ( 0 hom. )

Consequence

PKP2
NM_001005242.3 missense

Scores

5
14

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 4.09

Publications

2 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_benign. The variant received -1 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 10 uncertain in NM_001005242.3
BP4
Computational evidence support a benign effect (MetaRNN=0.25400215).
BS2
High AC in GnomAd4 at 7 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PKP2NM_001005242.3 linkc.974C>T p.Ala325Val missense_variant Exon 3 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.974C>T p.Ala325Val missense_variant Exon 3 of 13 1 NM_001005242.3 ENSP00000342800.5 Q99959-2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152190
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.0000294
Gnomad OTH
AF:
0.000956
GnomAD2 exomes
AF:
0.0000400
AC:
10
AN:
250080
AF XY:
0.0000369
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000622
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000458
AC:
67
AN:
1461838
Hom.:
0
Cov.:
33
AF XY:
0.0000371
AC XY:
27
AN XY:
727222
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33478
American (AMR)
AF:
0.0000894
AC:
4
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53408
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000522
AC:
58
AN:
1111984
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
4
9
13
18
22
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.000131
AC:
2
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68036
Other (OTH)
AF:
0.000956
AC:
2
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000825
Hom.:
0
Bravo
AF:
0.0000378
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:2
Mar 07, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces alanine with valine at codon 325 of the PKP2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with Brugada syndrome, who also carried a pathogenic variant in the SCN5A gene that could explain the observed phenotype (PMID: 31189615). This variant has also been observed in an individual affected with dilated cardiomyopathy (PMID: 37904629). This variant has also been identified in 12/281476 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Mar 16, 2016
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Arrhythmogenic right ventricular dysplasia 9 Uncertain:1
Jan 22, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 325 of the PKP2 protein (p.Ala325Val). This variant is present in population databases (rs201803918, gnomAD 0.006%). 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: 568756). 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 tolerated. 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

This missense variant replaces alanine with valine at codon 325 of the PKP2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with Brugada syndrome, who also carried a pathogenic variant in the SCN5A gene that could explain the observed phenotype (PMID: 31189615). This variant has also been observed in an individual affected with dilated cardiomyopathy (PMID: 37904629). This variant has also been identified in 12/281476 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not provided Uncertain:1
May 19, 2020
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 568756; Landrum et al., 2016) -

Cardiovascular phenotype Uncertain:1
Jan 08, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.974C>T (p.A325V) alteration is located in exon 3 (coding exon 3) of the PKP2 gene. This alteration results from a C to T substitution at nucleotide position 974, causing the alanine (A) at amino acid position 325 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Benign
-0.056
T
BayesDel_noAF
Benign
-0.14
CADD
Benign
17
DANN
Uncertain
0.99
DEOGEN2
Benign
0.20
.;T
Eigen
Benign
-0.11
Eigen_PC
Benign
-0.0041
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Benign
0.73
T;T
M_CAP
Uncertain
0.14
D
MetaRNN
Benign
0.25
T;T
MetaSVM
Benign
-0.60
T
MutationAssessor
Benign
2.0
M;M
PhyloP100
4.1
PrimateAI
Uncertain
0.53
T
PROVEAN
Benign
-1.0
N;N
REVEL
Uncertain
0.39
Sift
Benign
0.062
T;T
Sift4G
Benign
0.25
T;T
Polyphen
0.021
B;B
Vest4
0.39
MVP
0.88
MPC
0.17
ClinPred
0.19
T
GERP RS
5.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.063
gMVP
0.61
Mutation Taster
=74/26
polymorphism

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: rs201803918; hg19: chr12-33030840; COSMIC: COSV50736709; API