16-23624011-G-C

Position:

• chr16-23624011-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The ENST00000261584.9(PALB2):​c.2832C>G​(p.Ile944Met) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000657 in 152,092 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. I944N) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: PALB2 ENST00000261584.9 missense, splice_region
• Scores: Splicing: ADA: 0.9401
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.98

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]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PALB2	NM_024675.4	c.2832C>G	p.Ile944Met	missense_variant, splice_region_variant	8/13	ENST00000261584.9	NP_078951.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PALB2	ENST00000261584.9	c.2832C>G	p.Ile944Met	missense_variant, splice_region_variant	8/13	1	NM_024675.4	ENSP00000261584	P1
	ENST00000561764.1	n.531G>C		non_coding_transcript_exon_variant	4/4	2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152092 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000656

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.: 29

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152092 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74286

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000656

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

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

Sep 05, 2017

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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with PALB2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces isoleucine with methionine at codon 944 of the PALB2 protein (p.Ile944Met). The isoleucine residue is highly conserved and there is a small physicochemical difference between isoleucine and methionine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 24, 2021

The p.I944M variant (also known as c.2832C>G), located in coding exon 8 of the PALB2 gene, results from a C to G substitution at nucleotide position 2832. The isoleucine at codon 944 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is conserved. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Uncertain	0.012	T
BayesDel_noAF	Benign	-0.22
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.14	T;T
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.87	D;D
M_CAP	Benign	0.018	T
MetaRNN	Uncertain	0.56	D;D
MetaSVM	Benign	-0.76	T
MutationAssessor	Uncertain	2.6	.;M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.57	T
PROVEAN	Uncertain	-2.5	N;D
REVEL	Benign	0.18
Sift	Uncertain	0.0030	D;D
Sift4G	Uncertain	0.0090	D;D
Polyphen		1.0	.;D
Vest4		0.60
MutPred		0.22		.;Gain of helix (P = 0.062);
MVP		0.67
MPC		0.34
ClinPred		0.93	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.66
gMVP		0.55

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.94
dbscSNV1_RF	Benign	0.63
SpliceAI score (max)		0.020		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: rs1555459704; hg19: chr16-23635332;