Genetic Variant PALB2:p.Pro758Arg (chr16-23629881-G-C) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_024675.4(PALB2):c.2273C>G(p.Pro758Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,614,022 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign 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. P758T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

PALB2
NM_024675.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 1.45

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.1827513).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PALB2	NM_024675.4 link	c.2273C>G	p.Pro758Arg	missense_variant	Exon 5 of 13	ENST00000261584.9	NP_078951.2	Q86YC2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PALB2	ENST00000261584.9 link	c.2273C>G	p.Pro758Arg	missense_variant	Exon 5 of 13	1	NM_024675.4	ENSP00000261584.4		Q86YC2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152128

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000385

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251494

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135922

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461894

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000101

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152128

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74312

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000385

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

May 10, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 22941656, 28825143, 33471991) -

Jan 27, 2023

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The frequency of this variant in the general population, 0.0000071 (2/282892 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in an individual with breast cancer (PMID: 28825143 (2017)) and in individuals with breast cancer as well as in unaffected controls in a breast cancer association study (PMID: 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/genes/PALB2)). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded conflicting predictions that this variant is benign or damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -

Hereditary cancer-predisposing syndrome

Uncertain:2

Jan 18, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces proline with arginine at codon 758 of the PALB2 protein. Computational prediction suggests that this variant may not impact protein structure and function. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 28825143) and in a breast cancer case-control meta-analysis in 6/60466 cases and 2/53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID PALB2_010919). This variant has been identified in 2/282892 chromosomes 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. -

Sep 12, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P758R variant (also known as c.2273C>G), located in coding exon 5 of the PALB2 gene, results from a C to G substitution at nucleotide position 2273. The proline at codon 758 is replaced by arginine, an amino acid with dissimilar properties. This variant was reported in 6/60,466 breast cancer cases and in 2/53,461 controls (Dorling et al. N Engl J Med. 2021 02;384:428-439). In another study, this alteration was detected in a Chinese individual diagnosed with breast cancer (Zhang K et al. Breast Cancer Res. Treat., 2017 Dec;166:865-873). This amino acid position is not well 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. -

Familial cancer of breast;C1835817:Fanconi anemia complementation group N;C3150547:Pancreatic cancer, susceptibility to, 3

Uncertain:1

Aug 06, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Familial cancer of breast

Uncertain:1

Dec 08, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 758 of the PALB2 protein (p.Pro758Arg). This variant is present in population databases (rs746117401, gnomAD 0.01%). This missense change has been observed in individual(s) with breast cancer (PMID: 28825143). ClinVar contains an entry for this variant (Variation ID: 230502). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt PALB2 protein function with a positive predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

-0.26

BayesDel_noAF

Benign

-0.45

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Benign

0.21

T;D

Eigen

Benign

0.18

Eigen_PC

Benign

0.028

FATHMM_MKL

Benign

0.36

LIST_S2

Benign

0.73

T;T

M_CAP

Benign

0.012

MetaRNN

Benign

0.18

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

1.4

.;L

PrimateAI

Benign

0.27

PROVEAN

Uncertain

-4.0

D;D

REVEL

Benign

0.15

Sift

Uncertain

0.0040

D;D

Sift4G

Uncertain

0.0060

D;D

Polyphen

0.98

.;D

Vest4

0.35

MutPred

0.38

.;Loss of disorder (P = 0.1402);

MVP

0.62

MPC

0.31

ClinPred

0.64

GERP RS

6.0

Varity_R

0.099

gMVP

0.35

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over