rs397517005

Positions:

• chr12-32824141-AG-A

Variant summary

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

The NM_001005242.3(PKP2):​c.1577delC​(p.Ala526fs) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000137 in 1,460,116 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: PKP2 NM_001005242.3 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.51

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 (HGNC:):

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 12-32824141-AG-A is Pathogenic according to our data. Variant chr12-32824141-AG-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 45041.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr12-32824141-AG-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PKP2	NM_001005242.3	c.1577delC	p.Ala526fs	frameshift_variant	7/13	ENST00000340811.9	NP_001005242.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PKP2	ENST00000340811.9	c.1577delC	p.Ala526fs	frameshift_variant	7/13	1	NM_001005242.3	ENSP00000342800.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460116 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726484

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Arrhythmogenic right ventricular cardiomyopathy Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 15, 2010

The Ala570fs variant is predicted to cause a frameshift, which alters the protei n's amino acid sequence beginning at codon 570 and leads to a premature stop cod on 7 amino acids downstream. This alteration is then predicted to lead to a trun cated or absent protein (loss of function). Loss of function variants in the PKP 2 gene are common in patients with ARVC, increasing the likelihood that the Ala5 70fs variant is disease causing. In addition, the variant has been reported in one individual with a clinical diagnosis of ARVD/C as well as in the father, who was an obligate carrier. It was absent from 400 control chromosomes, supportin g a pathogenic role (Syrris 2006, please note that the authors refer to this var iant as Val570fs). In summary, the Ala570fs variant is likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

LitVar

Other links and lift over

dbSNP: rs397517005; hg19: chr12-32977075;