chr16-23607927-T-C

Variant names:

• chr16-23607927-T-C
• rs786201142
• NM_024675.4:c.3287A>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_024675.4(PALB2):​c.3287A>G​(p.Asn1096Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N1096K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 5.26
• Publications: 2 publications found

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]

PALB2 Gene-Disease associations (from GenCC):

• hereditary breast carcinoma

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
• Fanconi anemia complementation group N

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
• pancreatic cancer, susceptibility to, 3

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• familial ovarian cancer

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ENSG00000261723 (HGNC:58305):

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 39 uncertain in NM_024675.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.78

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024675.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PALB2	NM_024675.4	MANE Select	c.3287A>G	p.Asn1096Ser	missense	Exon 12 of 13	NP_078951.2
	PALB2	NM_001407296.1		c.3227A>G	p.Asn1076Ser	missense	Exon 11 of 12	NP_001394225.1
	PALB2	NM_001407297.1		c.3215A>G	p.Asn1072Ser	missense	Exon 11 of 12	NP_001394226.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PALB2	ENST00000261584.9	TSL:1 MANE Select	c.3287A>G	p.Asn1096Ser	missense	Exon 12 of 13	ENSP00000261584.4
	PALB2	ENST00000568219.5	TSL:1	c.2402A>G	p.Asn801Ser	missense	Exon 12 of 13	ENSP00000454703.2
	PALB2	ENST00000561514.3	TSL:5	c.3293A>G	p.Asn1098Ser	missense	Exon 12 of 13	ENSP00000460666.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461882 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727244

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0296732), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:2

May 13, 2019

Leiden Open Variation Database

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: curation

Curators: Marc Tischkowitz, Arleen D. Auerbach. Submitter to LOVD: Marc Tischkowitz.

Aug 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 1096 of the PALB2 protein (p.Asn1096Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with breast cancer (PMID: 25225577, 30638972). ClinVar contains an entry for this variant (Variation ID: 183891). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Hereditary cancer-predisposing syndrome Uncertain:2

Sep 06, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces asparagine with serine at codon 1096 of the PALB2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with bilateral breast cancer (PMID: 25225577). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.

Apr 14, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.N1096S variant (also known as c.3287A>G), located in coding exon 12 of the PALB2 gene, results from an A to G substitution at nucleotide position 3287. The asparagine at codon 1096 is replaced by serine, an amino acid with highly similar properties. This alteration was detected in a Portuguese high-risk breast cancer family but was not observed in a series of 311 additional Portuguese index cases (Hartley T, Hered Cancer Clin Pract 2014 ; 12(1):19). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Benign	-0.050	T
BayesDel_noAF	Benign	-0.31
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.13	T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Uncertain	0.87	D
M_CAP	Benign	0.026	D
MetaRNN	Pathogenic	0.78	D
MetaSVM	Benign	-0.43	T
MutationAssessor	Uncertain	2.0	M
PhyloP100		5.3
PrimateAI	Uncertain	0.59	T
PROVEAN	Uncertain	-4.2	D
REVEL	Uncertain	0.45
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.022	D
Polyphen		1.0	D
Vest4		0.87
MutPred		0.59		Loss of ubiquitination at K1098 (P = 0.0777)
MVP		0.80
MPC		0.25
ClinPred		1.0	D
GERP RS		6.1
Varity_R		0.87
gMVP		0.36

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

Other links and lift over

dbSNP: rs786201142; hg19: chr16-23619248; COSMIC: COSV106083106;