rs1555460671

chr16-23630409-GATAA-G

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.1741_1744del(p.Leu581ProfsTer17) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L581L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PALB2 NM_024675.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 2.69

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 16-23630409-GATAA-G is Pathogenic according to our data. Variant chr16-23630409-GATAA-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 482018.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PALB2	NM_024675.4	c.1741_1744del	p.Leu581ProfsTer17	frameshift_variant	5/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.1741_1744del	p.Leu581ProfsTer17	frameshift_variant	5/13	1	NM_024675.4	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/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 30, 2023	The c.1741_1744delTTAT pathogenic mutation, located in coding exon 5 of the PALB2 gene, results from a deletion of 4 nucleotides at nucleotide positions 1741 to 1744, causing a translational frameshift with a predicted alternate stop codon (p.L581Pfs*17). 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. -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 14, 2022	This variant deletes 4 nucleotides 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. -

Familial cancer of breast Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Mar 19, 2022	For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 482018). 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). This sequence change creates a premature translational stop signal (p.Leu581Profs*17) 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). -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Sep 11, 2023	This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Apr 26, 2017

This deletion of four nucleotides in PALB2 is denoted c.1741_1744delTTAT at the cDNA level and p.Leu581ProfsX17 (L581PfsX17) at the protein level. The normal sequence, with the bases that are deleted in brackets, is TTAT[delTTAT]CCTT. The deletion causes a frameshift which changes a Leucine to a Proline at codon 581, and creates a premature stop codon at position 17 of the new reading frame. Although this variant has not, to our knowledge, been reported in the literature, it is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. Based on the currently available information, we consider this deletion to be a likely pathogenic variant. -

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: rs1555460671; hg19: chr16-23641730;