16-23603601-C-G

Position:

• chr16-23603601-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_024675.4(PALB2):​c.3419G>C​(p.Trp1140Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000658 in 151,962 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. W1140G) has been classified as Likely benign.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 4.92

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.915

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PALB2	NM_024675.4	c.3419G>C	p.Trp1140Ser	missense_variant	13/13	ENST00000261584.9	NP_078951.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PALB2	ENST00000261584.9	c.3419G>C	p.Trp1140Ser	missense_variant	13/13	1	NM_024675.4	ENSP00000261584	P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151962 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000242

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

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

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151962 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74198

Gnomad4 AFR AF: 0.0000242

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jan 04, 2021	This missense variant replaces tryptophan with serine at codon 1140 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 not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 1/31380 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 30, 2018	The p.W1140S variant (also known as c.3419G>C), located in coding exon 13 of the PALB2 gene, results from a G to C substitution at nucleotide position 3419. The tryptophan at codon 1140 is replaced by serine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 10, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 410219). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.01%). This sequence change replaces tryptophan, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 1140 of the PALB2 protein (p.Trp1140Ser). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Benign	0.11	T;T
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.82	T;T
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.91	D;D
MetaSVM	Benign	-0.50	T
MutationAssessor	Uncertain	2.1	.;M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.67	T
PROVEAN	Pathogenic	-12	D;D
REVEL	Uncertain	0.45
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.87
MutPred		0.75		.;Gain of glycosylation at T1136 (P = 0.1113);
MVP		0.81
MPC		0.42
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.97
gMVP		0.84

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: rs1060502809; hg19: chr16-23614922;