PKP2

Chr 12AD

plakophilin 2

Also known as: ARVD9

This gene encodes plakophilin-2, a desmosomal protein that maintains cell-cell adhesion in cardiac myocytes and is required for proper cardiac electrical conduction and structural integrity. Mutations cause arrhythmogenic right ventricular dysplasia, an inherited cardiomyopathy that typically presents in adolescence or young adulthood with ventricular arrhythmias and sudden cardiac death risk. The condition follows autosomal dominant inheritance with variable penetrance and expressivity.

Summary from RefSeq, OMIM, UniProt
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Primary Disease Associations & Inheritance

Arrhythmogenic right ventricular dysplasia 9MIM #609040
AD
7
Active trials
61
Pubs (1 yr)
86
P/LP submissions
3%
P/LP missense
1.06
LOEUF
LOF
Mechanism· G2P
Clinical SummaryPKP2
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Gene-Disease Validity (ClinGen)
catecholaminergic polymorphic ventricular tachycardia · ADDisputed

Disputed — evidence questions this relationship

4 total gene-disease associations curated

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
75 unique Pathogenic / Likely Pathogenic· 276 VUS of 500 total submissions
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Clinical Trials
7 active or recruiting trials — potential therapeutic options may be available
📖
GeneReview available — PKP2
Authoritative clinical overview · Recommended first read
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Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.06LOEUF
pLI 0.000
Z-score 1.25
OE 0.79 (0.591.06)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.21Z-score
OE missense 1.03 (0.951.10)
513 obs / 499.6 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.79 (0.591.06)
00.351.4
Missense OE1.03 (0.951.10)
00.61.4
Synonymous OE0.98
01.21.6
LoF obs/exp: 32 / 40.6Missense obs/exp: 513 / 499.6Syn Z: 0.22
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitivePKP2-related arrhythmogenic right ventricular cardiomyopathyLOFAD
limitedPKP2-related dilated cardiomyopathyOTHERAD
limitedPKP2-related catecholaminergic polymorphic ventricular tachycardiaOTHERAD
limitedPKP2-related Brugada syndromeOTHERAD
DN
0.6259th %ile
GOF
0.5759th %ile
LOF
0.54top 25%

This gene has evidence for multiple mechanisms of pathogenicity (loss-of-function and dominant-negative). The Badonyi & Marsh model scores dominant-negative highest among its predictions, but genomic evidence (constraint, ClinVar variant spectrum, and literature) most strongly supports loss-of-function (haploinsufficiency). Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

LOF1 literature citation · 51% of P/LP variants are LoF
DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Literature Evidence

LOFPKP2 haploinsufficiency leads to I(Na) deficit in murine hearts.PMID:22764151

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.

ClinVar Variant Classifications

500 submitted variants in ClinVar

Classification Summary

Pathogenic46
Likely Pathogenic29
VUS276
Likely Benign132
Benign1
Conflicting4
46
Pathogenic
29
Likely Pathogenic
276
VUS
132
Likely Benign
1
Benign
4
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
22
0
24
0
46
Likely Pathogenic
16
2
11
0
29
VUS
3
246
27
0
276
Likely Benign
0
13
40
79
132
Benign
0
0
1
0
1
Conflicting
4
Total4126110379488

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

PKP2 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

PKP2 Arrhythmogenic Cardiomyopathy (PKP2-ACM)

A Phase 1, Dose Escalation Trial of RP-A601 in Subjects With PKP2 Variant-Mediated Arrhythmogenic Cardiomyopathy (PKP2-ACM)

RECRUITING
NCT05885412Phase PHASE1Rocket Pharmaceuticals Inc.Started 2023-08-29
RP-A601
Arrhythmogenic Right Ventricular Cardiomyopathy

Non-interventional Study of Seroprevalence of Pre-existing Antibodies Against Adenovirus-associated Virus Vector (AAV9) and the Progression of Disease in Patients With Plakophilin 2 (PKP2)-Associated Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

RECRUITING
NCT06311708Tenaya TherapeuticsStarted 2023-01-31
Arrhythmogenic CardiomyopathyPKP2-ACMPKP2-ARVC

Gene Therapy for ACM Due to a PKP2 Pathogenic Variant

ACTIVE NOT RECRUITING
NCT06109181Phase PHASE1, PHASE2Lexeo TherapeuticsStarted 2024-02-29
LX2020
Arrhythmogenic CardiomyopathyPKP2-ACMPKP2-ARVC

Long-term Follow-up Study of Gene Therapy for Arrhythmogenic Cardiomyopathy Due to a Plakophilin-2 Pathogenic Variant

ENROLLING BY INVITATION
NCT07050160Lexeo TherapeuticsStarted 2025-08-29
Arrhythmogenic Cardiomyopathies

Tissue and Metabolic Characterization of Arrhythmogenic Cardiomyopathies by Hybrid PET-MRI Imaging, Impact of the Observed Profiles on the Phenotype and on the Evolution of Cardiomyopathy

RECRUITING
NCT05450783Nantes University HospitalStarted 2022-09-01
Biocollection
Arrhythmogenic Right Ventricular Cardiomyopathy

Open-label, Dose Escalation Study of Safety and Preliminary Efficacy of TN-401 in Adults With PKP2 Mutation-associated ARVC

RECRUITING
NCT06228924Phase PHASE1Tenaya TherapeuticsStarted 2024-03-26
TN-401
Arrhythmogenic CardiomyopathyPKP2-ACMPKP2-ARVC

A Study to Assess Real-world Patient Characteristics and Clinical Course for Symptomatic Patients With PKP2-ACM

RECRUITING
NCT06976606Lexeo TherapeuticsStarted 2024-01-23
Clinical Literature
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