rs397517030

Positions:

• chr12-32877896-TCCCCCTGCGGCCGCCTGGCCGACAGTCAAGTGC-TGT

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001005242.3(PKP2):​c.951_983delinsAC​(p.His318GlnfsTer24) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. A317A) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PKP2 NM_001005242.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.68

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-32877897-CCCCCTGCGGCCGCCTGGCCGACAGTCAAGTGC-GT is Pathogenic according to our data. Variant chr12-32877897-CCCCCTGCGGCCGCCTGGCCGACAGTCAAGTGC-GT is described in ClinVar as [Pathogenic]. Clinvar id is 45091.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PKP2	NM_001005242.3	c.951_983delinsAC	p.His318GlnfsTer24	frameshift_variant	3/13	ENST00000340811.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PKP2	ENST00000340811.9	c.951_983delinsAC	p.His318GlnfsTer24	frameshift_variant	3/13	1	NM_001005242.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Arrhythmogenic right ventricular cardiomyopathy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Dec 15, 2021

The p.His318fsX24 variant in PKP2 has been identified in one individual with arrhythmogenic right ventricular cardiomyopathy (ARVC) and segregated with disease in at least 3 affected relatives, including one obligate carrier (LMM data). It was absent from large population studies. This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 318 and leads to a premature termination codon 24 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the ARVC gene is an established disease mechanism in autosomal dominant ARVC. In summary, this variant meets criteria to be classified as pathogenic for autosomal dominant ARVC. ACMG/AMP Criteria applied: PVS1; PM2_Supporting, PP1. -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs397517030; hg19: chr12-33030831;