16-23635230-C-G

Position:

• chr16-23635230-C-G

Variant summary

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

The ENST00000261584.9(PALB2):​c.1316G>C​(p.Gly439Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000041 in 1,461,844 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G439V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: PALB2 ENST00000261584.9 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 0.0800

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 -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.12510431).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PALB2	NM_024675.4	c.1316G>C	p.Gly439Ala	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.1316G>C	p.Gly439Ala	missense_variant	4/13	1	NM_024675.4	ENSP00000261584	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000400 AC: 1 AN: 249874 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135530

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

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: 0.00000410 AC: 6 AN: 1461844 Hom.: 0 Cov.: 33 AF XY: 0.00000550 AC XY: 4 AN XY: 727224

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000348

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

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	May 02, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 02, 2023	The p.G439A variant (also known as c.1316G>C), located in coding exon 4 of the PALB2 gene, results from a G to C substitution at nucleotide position 1316. The glycine at codon 439 is replaced by alanine, an amino acid with similar properties. This amino acid position is poorly 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 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 03, 2022	This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 439 of the PALB2 protein (p.Gly439Ala). This variant is present in population databases (no rsID available, gnomAD 0.003%). 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: 818890). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 25, 2023	- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 11, 2019

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.27	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	11
DANN	Benign	0.93
DEOGEN2	Benign	0.14	T;T
Eigen	Benign	-0.56
Eigen_PC	Benign	-0.76
FATHMM_MKL	Benign	0.35	N
LIST_S2	Benign	0.78	T;T
M_CAP	Benign	0.026	D
MetaRNN	Benign	0.13	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	2.0	.;M
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.32	T
PROVEAN	Uncertain	-3.1	D;D
REVEL	Benign	0.040
Sift	Uncertain	0.022	D;D
Sift4G	Benign	1.0	T;T
Polyphen		0.84	.;P
Vest4		0.26
MutPred		0.22		.;Gain of helix (P = 0.027);
MVP		0.35
MPC		0.34
ClinPred		0.55	D
GERP RS		-2.3
Varity_R		0.12
gMVP		0.40

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: rs537258442; hg19: chr16-23646551;