16-23634993-G-C

Position:

• chr16-23634993-G-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.1553C>G​(p.Ser518Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PALB2 NM_024675.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 3.12

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 16-23634993-G-C is Pathogenic according to our data. Variant chr16-23634993-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 410213.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.1553C>G	p.Ser518Ter	stop_gained	4/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.1553C>G	p.Ser518Ter	stop_gained	4/13	1	NM_024675.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jul 25, 2023	This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Ser518*) 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). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. ClinVar contains an entry for this variant (Variation ID: 410213). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Sep 11, 2023	This variant is considered pathogenic. This variant creates a termination codon and is predicted to result in premature protein truncation. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 05, 2022	The p.S518* pathogenic mutation (also known as c.1553C>G), located in coding exon 4 of the PALB2 gene, results from a C to G substitution at nucleotide position 1553. This changes the amino acid from a serine to a stop codon within coding exon 4. 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	Nov 23, 2020	This variant changes 1 nucleotide in exon 4 of the PALB2 gene, creating a 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. -

PALB2-related disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

May 30, 2023

The PALB2 c.1553C>G (p.Ser518Ter) nonsense variant results in the loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. To our knowledge, this variant has not been reported in the peer-reviewed literature. This variant is not observed in version 2.1.1 or version 3.1.2 of the Genome Aggregation Database. The c.1553C>G variant has been classified as pathogenic by at least three submitters in ClinVar. Based on the available evidence, the c.1553C>G (p.Ser518Ter) variant is classified as pathogenic for PALB2-related cancer susceptibility. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Uncertain	0.96	D
MutationTaster	Benign	1.0	A
Vest4		0.77
GERP RS		4.7

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: rs1060502805; hg19: chr16-23646314; COSMIC: COSV55169206; COSMIC: COSV55169206;