16-23629683-CA-C

Position:

• chr16-23629683-CA-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_024675.4(PALB2):​c.2470del​(p.Cys824ValfsTer27) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,892 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: 6.8e-7 (0 hom.)
• Consequence: PALB2 NM_024675.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: -0.397

Genes affected

PALB2 (HGNC:26144): (partner and localizer of BRCA2) This gene encodes a protein that may function in tumor suppression. This protein binds to and colocalizes with the breast cancer 2 early onset protein (BRCA2) in nuclear foci and likely permits the stable intranuclear localization and accumulation of BRCA2. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 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 16-23629683-CA-C is Pathogenic according to our data. Variant chr16-23629683-CA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 230043.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-23629683-CA-C is described in Lovd as [Likely_pathogenic]. Variant chr16-23629683-CA-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PALB2	NM_024675.4	c.2470del	p.Cys824ValfsTer27	frameshift_variant	5/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.2470del	p.Cys824ValfsTer27	frameshift_variant	5/13	1	NM_024675.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461892 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727248

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jul 29, 2023	This sequence change creates a premature translational stop signal (p.Cys824Valfs*27) in the PALB2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PALB2 are known to be pathogenic (PMID: 17200668, 17200671, 17200672, 24136930, 25099575). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 230043). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. This variant is not present in population databases (gnomAD no frequency). -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Sep 12, 2023	This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Oct 17, 2023	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 16, 2022	This variant deletes 1 nucleotide in exon 5 of the PALB2 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. To our knowledge, this variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of PALB2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 14, 2023	The c.2470delT pathogenic mutation, located in coding exon 5 of the PALB2 gene, results from a deletion of one nucleotide at nucleotide position 2470, causing a translational frameshift with a predicted alternate stop codon (p.C824Vfs*27). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Jan 14, 2021

This frameshift variant causes the premature termination of PALB2 protein synthesis. It has been reported along with PALB2 c.2834+2T>C in an individual with Fanconi anemia in the published literature (PMID: 30792206 (2019)). Therefore, the variant is classified as pathogenic. -

Gastric cancer Pathogenic:1

Pathogenic, no assertion criteria provided

research

Laboratory for Genotyping Development, RIKEN

Jul 01, 2021

- -

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: rs876658348; hg19: chr16-23641004;