Genetic Information

Gene & Transcript Details

Gene
PALB2
Transcript
NM_024675.4 MANE Select
Total Exons
Reference Sequence
NC_000016.9
Alternative Transcripts
IDStatusDetails
NM_024675.4 MANE Select 4008 nt | 154–3714
NM_024675.3 RefSeq Select 4069 nt | 201–3761

Variant Details

HGVS Notation
NM_024675.4:c.2474G>C
Protein Change
R825T
Location
Exon 5 (Exon 5 of )
5
5'Exon Structure3'
Functional Consequence
Loss of Function
Alternate Identifiers

Clinical & Population Data

Population Frequency

gnomAD
Global Frequency
0.0163 in 100,000
Extremely Rare
ACMG Criteria Applied PM2
This variant is absent or extremely rare in population databases (PM2 criteria applies).

ClinVar

Open
Classification
Uncertain Significance (VUS)
2 publications
Publications List
PMID: 26689913

Variant summary: PALB2 c.2474G>C (p.Arg825Thr) 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 0.00016 in 251430 control chromosomes, predominantly at a frequency of 0.0022 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 14.079 fold of the estimated maximal expected allele frequency for a pathogenic variant in PALB2 causing Hereditary Breast And Ovarian Cancer Syndrome phenotype (0.00016), strongly suggesting that the variant is a benign polymorphism found primarily in populations of East Asian origin. c.2474G>C has been reported in the literature in individuals affected with various types of cancers includin leiomyosarcoma, stomach adenocarcinoma, breast cancer and urothelial carcinoma, all without strong evidence for causality (Yang_2015, Lu_2015, Kwong_2020, Xie_2018, Yang_2021). These reports do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Eight clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation; four classified as VUS while four classified as likely benign. Based on the evidence outlined above, the variant was classified as likely benign.

PMID: 25085752

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].

Clinical Statement

"This variant has been reported in ClinVar as Uncertain significance (3 clinical laboratories) and as Likely benign (9 clinical laboratories)."

COSMIC Somatic Evidence

Open
COSMIC ID
Recurrence
0 occurrences
PM1 Criteria
Not Applied
COSMIC Database Preview
COSMIC Preview
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Functional Impact & Domains

Functional Domain

Hotspot Status
Not a hotspot
Domain Summary
This variant is not located in a mutational hotspot or critical domain.
Related Variants in This Domain
No evidence of other pathogenic variants at this position in gene PALB2.

Functional Studies & Therapeutic Relevance

Functional Summary

The PALB2 R825T variant has not been functionally characterized.

Database Previews
OncoKB
OncoKB Preview
JAX-CKB
JAX-CKB Preview

Click on previews to view full database entries. External databases may require institutional access.

Computational Analysis

Pathogenicity Predictions

SpliceAI
Predictor Consensus
Mixed/VUS
PP3 Applied
No
REVEL Score
0.03
Threshold: ≥0.75 = PP3 applied

SpliceAI Scores

Window: ±500bp
Effect Type Score Position
- Acceptor Loss (AL) 0.0 -405 bp
- Donor Loss (DL) 0.01 -40 bp
+ Acceptor Gain (AG) 0.0 279 bp
+ Donor Gain (DG) 0.01 -146 bp
High impact (≥0.5) Medium impact (0.2-0.49) Low impact (<0.2)

VCEP Guidelines

Applied ACMG/AMP Criteria (VCEP Specific)

Filter Criteria:
PVS1

PVS1 (Not Applied)

According to VCEP guidelines, PVS1 is for null variants in PALB2 per the PVS1 decision tree. The rule for PVS1 is: "Very Strong Use PALB2 PVS1 Decision Tree". The evidence shows this variant is a missense change (p.R825T), not a null variant. Therefore, this criterion is not applied.

PS1

PS1 (Not Applied)

According to VCEP guidelines, PS1 applies when the same amino acid change as a previously established pathogenic variant is observed. The rule for PS1 is: "Strong: Same amino acid change as a previously established pathogenic variant regardless of nucleotide change". No such pathogenic R825T change has been reported. Therefore, this criterion is not applied.

PS2

PS2 (Not Applied)

According to standard ACMG guidelines, PS2 applies for confirmed de novo occurrences. There is no de novo evidence. Therefore, this criterion is not applied.

PS3

PS3 (Not Applied)

According to standard ACMG guidelines, PS3 requires well-established functional studies showing a deleterious effect. No functional data are available for p.R825T. Therefore, this criterion is not applied.

PS4

PS4 (Not Applied)

According to VCEP guidelines, PS4 requires case-control studies meeting specific statistical thresholds. There are no such data for p.R825T. Therefore, this criterion is not applied.

PM1

PM1 (Not Applied)

According to standard ACMG guidelines, PM1 applies to variants in mutational hotspots or critical functional domains. No evidence places R825 in a known hotspot or domain. Therefore, this criterion is not applied.

PM2

PM2 (Not Applied)

According to VCEP guidelines, PM2_Supporting requires absence or ≤1/300,000 alleles in gnomAD. The rule: "Supporting: Variant absent in gnomAD or present in ≤1/300,000 alleles". The observed global MAF is 0.0163% (46/282,834), exceeding the threshold. Therefore, this criterion is not applied.

PM3

PM3 (Not Applied)

According to VCEP guidelines, PM3 applies to variants in trans with a pathogenic variant for recessive disorders. No evidence of trans occurrence is available. Therefore, this criterion is not applied.

PM4

PM4 (Not Applied)

According to standard ACMG guidelines, PM4 applies to protein length changes due to in‐frame indels or stop-loss. The variant is a missense change. Therefore, this criterion is not applied.

PM5

PM5 (Not Applied)

According to VCEP guidelines, PM5_Supporting applies to frameshifting or truncating variants upstream of p.Tyr1183. The rule: "Supporting: Apply to frameshifting or truncating variants with premature termination codons upstream of p.Tyr1183". p.R825T is a missense variant. Therefore, this criterion is not applied.

PM6

PM6 (Not Applied)

According to standard ACMG guidelines, PM6 applies to assumed de novo occurrences without confirmation. No de novo evidence is available. Therefore, this criterion is not applied.

PP1

PP1 (Not Applied)

According to VCEP guidelines, PP1 applies for segregation evidence. No family segregation data are available. Therefore, this criterion is not applied.

PP2

PP2 (Not Applied)

According to standard ACMG guidelines, PP2 applies to missense variants in genes with low rates of benign missense and where missense is a common disease mechanism. PALB2 pathogenesis is primarily loss‐of‐function; missense contribution is unclear. Therefore, this criterion is not applied.

PP3

PP3 (Not Applied)

According to VCEP guidelines, PP3 for protein predictions is not used; for RNA, it requires impact on splicing. The SpliceAI score is 0.01 (no impact). Therefore, PP3 is not applied.

PP4

PP4 (Not Applied)

According to standard ACMG guidelines, PP4 applies to highly specific phenotype–genotype correlations. No phenotype data are provided. Therefore, this criterion is not applied.

PP5

PP5 (Not Applied)

According to standard ACMG guidelines, PP5 (reputable source) is discouraged. Although ClinVar includes Likely benign assertions, ACMG recommends not applying PP5. Therefore, this criterion is not applied.

BA1

BA1 (Not Applied)

According to VCEP guidelines, BA1 requires filtering allele frequency >0.1%. The observed MAF is 0.0163%, below 0.1%. Therefore, this criterion is not applied.

BS1

BS1 (Strong)

According to VCEP guidelines, BS1_Strong: "GnomAD Filtering Allele Frequency greater than expected for disease >0.01%". The observed global MAF is 0.0163%, which is >0.01%. Therefore, this criterion is applied at Strong strength.

BS2

BS2 (Not Applied)

According to VCEP guidelines, BS2 applies when observed in healthy adult individuals for dominant disorders. No such data are available. Therefore, this criterion is not applied.

BS3

BS3 (Not Applied)

According to standard ACMG guidelines, BS3 requires well‐established functional studies showing no deleterious effect. No functional data are available. Therefore, this criterion is not applied.

BS4

BS4 (Not Applied)

According to VCEP guidelines, BS4 applies for non‐segregation in affected members. No segregation data are available. Therefore, this criterion is not applied.

BP1

BP1 (Supporting)

According to VCEP guidelines, BP1_Supporting: "Apply to all missense variants" in PALB2. The variant is a missense change (p.R825T). Therefore, this criterion is applied at Supporting strength.

BP2

BP2 (Not Applied)

According to standard ACMG guidelines, BP2 applies when a variant is observed in trans with a pathogenic variant for a dominant disorder or in cis with a benign variant. No such data are available. Therefore, this criterion is not applied.

BP3

BP3 (Not Applied)

According to standard ACMG guidelines, BP3 applies to in‐frame indels in repetitive regions. The variant is a missense change. Therefore, this criterion is not applied.

BP4

BP4 (Supporting)

According to VCEP guidelines, BP4_Supporting for RNA: "At least one well-established in silico predictor shows no impact on splicing". The SpliceAI score is 0.01, indicating negligible splicing impact. Therefore, this criterion is applied at Supporting strength.

BP5

BP5 (Not Applied)

According to standard ACMG guidelines, BP5 applies when a variant is found in a case with an alternate molecular basis for disease. No such data are available. Therefore, this criterion is not applied.

BP6

BP6 (Not Applied)

According to standard ACMG guidelines, BP6 (reputable source benign) is discouraged. ClinVar assertions exist but ACMG advises against. Therefore, this criterion is not applied.

BP7

BP7 (Not Applied)

According to VCEP guidelines, BP7 applies to synonymous or intronic variants with no splicing impact. The variant is missense. Therefore, this criterion is not applied.