rs876658196

chr16-23603628-A-Gchr16-23603628-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM5 BP4

The NM_024675.4(PALB2):c.3392T>C(p.Ile1131Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000684 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. I1131V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:9
• Conservation: PhyloP100: 5.84

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 1 ACMG points.

• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-23603628-A-CC is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2580969.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.29310337).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PALB2	NM_024675.4	c.3392T>C	p.Ile1131Thr	missense_variant	13/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.3392T>C	p.Ile1131Thr	missense_variant	13/13	1	NM_024675.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461882 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 727240

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: 0.00000809

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:9

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:4

Uncertain significance, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 30, 2023	This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	May 04, 2017	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 07, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jul 08, 2023	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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This variant disrupts the WD40-like repeats of the PALB2 protein, which are required for interactions with the BRCA2, POLH, and RAD51C proteins (PMID: 24141787, 24485656). While functional studies have not been performed to directly test the effect of this variant on PALB2 protein function, this suggests that disruption of this region of the protein is causative of disease. This variant disrupts the WD40-like repeats of the PALB2 protein, which are required for interactions with the BRCA2, POLH, and RAD51C proteins (PMID: 24141787, 24485656). While functional studies have not been performed to directly test the effect of this variant on PALB2 protein function, this suggests that disruption of this region of the protein is causative of disease. ClinVar contains an entry for this variant (Variation ID: 229790). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1131 of the PALB2 protein (p.Ile1131Thr). -

Hereditary cancer-predisposing syndrome Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 07, 2023	This missense variant replaces isoleucine with threonine at codon 1131 of the PALB2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with PALB2-related disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 03, 2022	The p.I1131T variant (also known as c.3392T>C), located in coding exon 13 of the PALB2 gene, results from a T to C substitution at nucleotide position 3392. The isoleucine at codon 1131 is replaced by threonine, 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. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Jun 12, 2021	- -

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	May 16, 2016	Variant summary: The PALB2 c.3392T>C (p.Ile1131Thr) variant involves the alteration of a conserved nucleotide. 3/4 in silico tools predict a damaging outcome. This variant is absent in approximately 121182 control chromosomes from the large and broad populations of ExAC. The variant of interest has not, to our knowledge, been reported in affected individuals via publications and/or reputable databases/clinical diagnostic laboratories; nor evaluated for functional impact by in vivo/vitro studies. Because of the absence of clinical information and the lack of functional studies, the variant has currently been classified as a variant of uncertain significance (VUS) until additional information becomes available. -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 16, 2022	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 24485656, 19609323, 20871615) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.59
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.41
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Benign	0.019	T;T
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.51
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.82	T;T
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.29	T;T
MetaSVM	Benign	-0.93	T
MutationTaster	Benign	0.71	D
PrimateAI	Benign	0.35	T
PROVEAN	Uncertain	-2.4	N;D
Sift	Uncertain	0.014	D;D
Sift4G	Uncertain	0.0090	D;D
Polyphen		0.60	.;P
Vest4		0.49
MutPred		0.55		.;Loss of stability (P = 0.0087);
MVP		0.62
MPC		0.19
ClinPred		0.89	D
GERP RS		5.6
Varity_R		0.38
gMVP		0.39

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: rs876658196; hg19: chr16-23614949;