chr16-23635054-C-T

Position:

• chr16-23635054-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_024675.4(PALB2):​c.1492G>A​(p.Asp498Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D498Y) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: -0.262

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 Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.043456346).
• BP6: Variant 16-23635054-C-T is Benign according to our data. Variant chr16-23635054-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 410161.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PALB2	NM_024675.4	c.1492G>A	p.Asp498Asn	missense_variant	4/13	ENST00000261584.9	NP_078951.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PALB2	ENST00000261584.9	c.1492G>A	p.Asp498Asn	missense_variant	4/13	1	NM_024675.4	ENSP00000261584	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461880 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727238

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Familial cancer of breast;C1835817:Fanconi anemia complementation group N;C3150547:Pancreatic cancer, susceptibility to, 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Apr 22, 2022

- -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 30, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 498 of the PALB2 protein (p.Asp498Asn). This variant is not present in population databases (gnomAD no frequency). 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: 410161). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt PALB2 protein function. 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 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 14, 2024

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.39	T
BayesDel_noAF	Benign	-0.79
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Benign	0.020	T;T
Eigen	Benign	-0.90
Eigen_PC	Benign	-0.90
FATHMM_MKL	Benign	0.062	N
LIST_S2	Benign	0.53	T;T
M_CAP	Benign	0.0091	T
MetaRNN	Benign	0.043	T;T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	0.49	.;N
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.25	T
PROVEAN	Benign	-1.5	N;N
REVEL	Benign	0.10
Sift	Benign	0.26	T;T
Sift4G	Benign	0.34	T;T
Polyphen		0.019	.;B
Vest4		0.062
MutPred		0.14		.;Gain of MoRF binding (P = 0.0509);
MVP		0.21
MPC		0.053
ClinPred		0.10	T
GERP RS		-0.22
Varity_R		0.042
gMVP		0.12

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: rs75023630; hg19: chr16-23646375;