chr16-23635040-C-G

Variant names:

• chr16-23635040-C-G
• rs371142570
• NM_024675.4:c.1506G>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_024675.4(PALB2):​c.1506G>C​(p.Lys502Asn) 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 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 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. K502R) has been classified as Uncertain significance.

• 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:3 B:2
• Conservation: PhyloP100: -2.10
• Publications: 3 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

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.05523923).
• BP6: Variant 16-23635040-C-G is Benign according to our data. Variant chr16-23635040-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 482009.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PALB2	NM_024675.4	c.1506G>C	p.Lys502Asn	missense_variant	Exon 4 of 13	ENST00000261584.9	NP_078951.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PALB2	ENST00000261584.9	c.1506G>C	p.Lys502Asn	missense_variant	Exon 4 of 13	1	NM_024675.4	ENSP00000261584.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251468 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727244

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

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: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000233 AC: 2

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Familial cancer of breast Uncertain:2

Oct 06, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 07, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 502 of the PALB2 protein (p.Lys502Asn). This variant is present in population databases (rs371142570, gnomAD 0.0009%). 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: 482009). 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 not expected to disrupt PALB2 protein function with a negative 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. -

Hereditary cancer-predisposing syndrome Benign:2

May 19, 2017

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 23, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

not provided Uncertain:1

Feb 13, 2025

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 indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 35585550) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.36
BayesDel_addAF	Benign	-0.40	T
BayesDel_noAF	Benign	-0.81
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Benign	0.030	T;T
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.088	N
LIST_S2	Benign	0.76	T;T
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.055	T;T
MetaSVM	Benign	-0.97	T
MutationAssessor	Benign	1.7	.;L
PhyloP100		-2.1
PrimateAI	Benign	0.35	T
PROVEAN	Benign	-1.5	N;N
REVEL	Benign	0.032
Sift	Benign	0.14	T;T
Sift4G	Benign	0.72	T;T
Polyphen		0.16	.;B
Vest4		0.12
MutPred		0.28		.;Loss of ubiquitination at K502 (P = 8e-04);
MVP		0.17
MPC		0.21
ClinPred		0.086	T
GERP RS		-1.3
Varity_R		0.057
gMVP		0.21

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: rs371142570; hg19: chr16-23646361;