rs45585833

Positions:

• chr16-23635690-G-A
• chr16-23635690-G-C
• chr16-23635690-G-T

Variant summary

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

The NM_024675.4(PALB2):​c.856C>T​(p.Pro286Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 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. P286L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000020 (0 hom.)
• Consequence: PALB2 NM_024675.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7 B:1
• Conservation: PhyloP100: -0.233

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=0.09268662).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PALB2	NM_024675.4	c.856C>T	p.Pro286Ser	missense_variant	4/13	ENST00000261584.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PALB2	ENST00000261584.9	c.856C>T	p.Pro286Ser	missense_variant	4/13	1	NM_024675.4	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152178 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251406 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135886

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 SAS 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: 0.0000198 AC: 29 AN: 1461816 Hom.: 0 Cov.: 32 AF XY: 0.0000165 AC XY: 12 AN XY: 727202

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: 0.0000252

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152178 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74336

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Familial cancer of breast Uncertain:2 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Nov 27, 2023	This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 286 of the PALB2 protein (p.Pro286Ser). This variant is present in population databases (rs45585833, gnomAD 0.0009%). This missense change has been observed in individual(s) with breast cancer (PMID: 17200668, 27328445). ClinVar contains an entry for this variant (Variation ID: 128147). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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	Counsyl	May 10, 2016	- -
Likely benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 31, 2023	This variant is considered likely benign. This variant is strongly associated with less severe personal and family histories of cancer, typical for individuals without pathogenic variants in this gene [PMID: 25085752]. -

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Apr 03, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Sep 28, 2023	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Observed in control individuals in a breast cancer case-control study (Rahman et al., 2007); This variant is associated with the following publications: (PMID: 27328445, 19369211, 25085752, 17200668) -

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Sep 08, 2020	This missense variant replaces proline with serine at codon 286 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 hereditary cancer in the literature. This variant has been identified in 1/251406 chromosomes 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	May 18, 2023	The p.P286S variant (also known as c.856C>T), located in coding exon 4 of the PALB2 gene, results from a C to T substitution at nucleotide position 856. The proline at codon 286 is replaced by serine, an amino acid with similar properties. In one study, this alteration was identified in 0/923 familial breast cancer cases and 2/1084 controls (Rahman N et al. Nat. Genet. 2007 Feb;39:165-7). This amino acid position is not well conserved in available vertebrate species, and serine is the reference amino acid in other 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. -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Mar 30, 2023

Variant summary: PALB2 c.856C>T (p.Pro286Ser) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251406 control chromosomes, exclusively observed in 1 female individual within the (non-Finnish) European subpopulation (gnomAD v2.1.1). In addition, the variant was reported in 1 (non-Finnish) European male control individual in gnomAD v3 while, it was also reported in 3/7325 European American women, older than age 70 years, who have never had cancer (FLOSSIES database). Lastly, c.856C>T has been reported in the literature in a familial breast cancer study conducted in Great Britain, where it was found in 2/1084 healthy control individuals (all 48 years of age), and in none of the 923 familial breast cancer cases (Rahman 2007). In summary, this variant has been reported in 7 healthy controls of European descent so far but it has not been reported in patients. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.72
CADD	Benign	1.0
DANN	Uncertain	0.98
DEOGEN2	Benign	0.31	T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.12	N
LIST_S2	Benign	0.60	T
M_CAP	Benign	0.018	T
MetaRNN	Benign	0.093	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.4	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.20	T
PROVEAN	Uncertain	-2.5	N
REVEL	Benign	0.014
Sift	Benign	0.52	T
Sift4G	Benign	0.52	T
Polyphen		0.14	B
Vest4		0.16
MutPred		0.59		Gain of sheet (P = 0.0344);
MVP		0.25
MPC		0.065
ClinPred		0.057	T
GERP RS		-1.2
Varity_R		0.037
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

Publications

LitVar

Other links and lift over

dbSNP: rs45585833; hg19: chr16-23647011;