rs1060502763

Positions:

• chr16-23629209-A-C
• chr16-23629209-A-T

Variant summary

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

The NM_024675.4(PALB2):​c.2581T>G​(p.Leu861Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts 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. L861F) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.21

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: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PALB2	NM_024675.4	c.2581T>G	p.Leu861Val	missense_variant	6/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.2581T>G	p.Leu861Val	missense_variant	6/13	1	NM_024675.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 19, 2016

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a PALB2-related disease. This sequence change replaces leucine with valine at codon 861 of the PALB2 protein (p.Leu861Val). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and valine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 30, 2024

The p.L861V variant (also known as c.2581T>G), located in coding exon 6 of the PALB2 gene, results from a T to G substitution at nucleotide position 2581. The leucine at codon 861 is replaced by valine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Benign	-0.041	T
BayesDel_noAF	Benign	-0.30
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Benign	0.074	T;T
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Benign	0.84	T;T
M_CAP	Benign	0.039	D
MetaRNN	Benign	0.40	T;T
MetaSVM	Benign	-0.51	T
MutationAssessor	Uncertain	2.5	.;M
MutationTaster	Benign	1.0	D
PrimateAI	Benign	0.48	T
PROVEAN	Benign	-1.9	N;N
REVEL	Benign	0.21
Sift	Uncertain	0.0090	D;D
Sift4G	Uncertain	0.051	T;D
Polyphen		1.0	.;D
Vest4		0.52
MutPred		0.24		.;Gain of methylation at K862 (P = 0.0336);
MVP		0.64
MPC		0.30
ClinPred		0.91	D
GERP RS		6.2
Varity_R		0.42
gMVP		0.38

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.95		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.95		Position offset: 1
DS_DL_spliceai		0.20		Position offset: -5

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1060502763; hg19: chr16-23640530;