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.2329G>A
Protein Change
D777N
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
0.00159 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: 25225577

The PALB2 c.2329G>A (p.Asp777Asn) variant has been reported in the published literature in individuals affected with breast and/or ovarian cancer (PMID: 30309218 (2018)), as well as colorectal cancer (PMID: 28944238 (2017), 33309985 (2020)). It has also been identified in affected and reportedly healthy individuals in large-scale breast cancer association studies (PMIDs: 30287823 (2018), 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/)). The frequency of this variant in the general population (Genome Aggregation Database, http://gnomad.broadinstitute.org) is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant.

Clinical Statement

"This variant has been reported in ClinVar as Likely benign (3 clinical laboratories) and as Uncertain significance (5 clinical laboratories)."

COSMIC Somatic Evidence

Open
COSMIC ID
COSM1219154
Recurrence
2 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 D777N 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
0.0
Threshold: ≥0.75 = PP3 applied

SpliceAI Scores

Window: ±500bp
Effect Type Score Position
- Acceptor Loss (AL) 0.01 134 bp
- Donor Loss (DL) 0.0 -185 bp
+ Acceptor Gain (AG) 0.0 -94 bp
+ Donor Gain (DG) 0.0 -291 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, the rule for PVS1 is: "Use PALB2 PVS1 Decision Tree Modification Type: Gene-specific,Strength." The evidence shows this variant is a missense change (D777N) not predicted to cause loss of function. Therefore, this criterion is not applied.

PS1

PS1 (Not Applied)

According to VCEP guidelines, the rule for PS1 is: "Strong Use PALB2 PS1 Splicing table Modification Type: General recommendation." The evidence shows no previously established pathogenic variant results in the same D777N amino acid change. Therefore, this criterion is not applied.

PS2

PS2 (Not Applied)

According to standard ACMG guidelines, the rule for PS2 is: "De novo (both maternity and paternity confirmed) in a patient with the disease and no family history." There is no de novo data available for this variant. Therefore, this criterion is not applied.

PS3

PS3 (Not Applied)

According to standard ACMG guidelines, the rule for PS3 is: "Well-established functional studies show a deleterious effect on the gene or gene product." No functional assays have been performed for PALB2 D777N. Therefore, this criterion is not applied.

PS4

PS4 (Not Applied)

According to VCEP guidelines, the rule for PS4 is: "Strong Case-control studies; p-value ≤.05 AND (Odds ratio, hazard ratio, or relative risk ≥3 OR lower 95% CI ≥1.5)." No case-control data are available. Therefore, this criterion is not applied.

PM1

PM1 (Not Applied)

According to standard ACMG guidelines, the rule for PM1 is: "Located in a mutational hot spot and/or critical and well‐established functional domain without benign variation." D777N does not lie in a recognized PALB2 hotspot or critical domain. Therefore, this criterion is not applied.

PM2

PM2 (Not Applied)

According to VCEP guidelines, the rule for PM2 (Supporting) is: "Variant absent in gnomAD or present in ≤1/300,000 alleles." The variant MAF=0.00159% (4/251,432), which exceeds 1/300,000 (0.00033%). Therefore, this criterion is not applied.

PM3

PM3 (Not Applied)

According to VCEP guidelines, the rule for PM3 is: "Use Fanconi Anemia PM3 tables (Strong/Moderate/Supporting)." No evidence of the variant in trans with another pathogenic PALB2 variant exists. Therefore, this criterion is not applied.

PM4

PM4 (Not Applied)

According to standard ACMG guidelines, the rule for PM4 is: "Protein length changes due to in‐frame deletions/insertions in a non‐repeat region or stop‐loss variants." This is a missense variant without protein length change. Therefore, this criterion is not applied.

PM5

PM5 (Not Applied)

According to VCEP guidelines, the rule for PM5 is: "Supporting Apply to frameshifting or truncating variants with premature termination codons upstream of p.Tyr1183." This is a missense variant. Therefore, this criterion is not applied.

PM6

PM6 (Not Applied)

According to standard ACMG guidelines, the rule for PM6 is: "Assumed de novo, but without confirmation of paternity and maternity." No such data are available. Therefore, this criterion is not applied.

PP1

PP1 (Not Applied)

According to VCEP guidelines, the rule for PP1 is: "LOD ≥0.3 for Supporting, ≥0.6 for Moderate, ≥1.26 for Strong based on segregation evidence." No familial segregation data are available. Therefore, this criterion is not applied.

PP2

PP2 (Not Applied)

According to standard ACMG guidelines, the rule for PP2 is: "Missense variant in a gene with a low rate of benign missense variation and where missense variants are a common mechanism of disease." PALB2 pathogenicity is driven primarily by loss‐of‐function, and missense variants are not established as a common mechanism. Therefore, this criterion is not applied.

PP3

PP3 (Not Applied)

According to VCEP guidelines, the rule for PP3 is: "Protein: Do not use; RNA: At least one well‐established in silico predictor shows impact on splicing." In silico splicing prediction (SpliceAI) shows no impact. Therefore, this criterion is not applied.

PP4

PP4 (Not Applied)

According to standard ACMG guidelines, the rule for PP4 is: "Patient’s phenotype or family history is highly specific for a disease with a single genetic etiology." No phenotype or clinical data are provided. Therefore, this criterion is not applied.

PP5

PP5 (Not Applied)

According to standard ACMG guidelines, the rule for PP5 is: "Reputable source reports variant as pathogenic without available evidence." ClinVar submissions are conflicting (Likely benign and VUS) and this rule is discouraged. Therefore, this criterion is not applied.

BA1

BA1 (Not Applied)

According to VCEP guidelines, the rule for BA1 (Stand Alone) is: "GnomAD Filtering Allele Frequency >0.1%." The variant MAF=0.00159% is below 0.1%. Therefore, this criterion is not applied.

BS1

BS1 (Not Applied)

According to VCEP guidelines, the rule for BS1 (Strong) is: "GnomAD Filtering Allele Frequency >0.01%." The variant MAF=0.00159% is below 0.01%. Therefore, this criterion is not applied.

BS2

BS2 (Not Applied)

According to VCEP guidelines, the rule for BS2 is: "Per Fanconi Anemia BS2 tables (Strong/Moderate/Supporting)." No observations in healthy adults have been reported. Therefore, this criterion is not applied.

BS3

BS3 (Not Applied)

According to standard ACMG guidelines, the rule for BS3 is: "Well-established functional studies show no deleterious effect." No functional data exist. Therefore, this criterion is not applied.

BS4

BS4 (Not Applied)

According to VCEP guidelines, the rule for BS4 is: "LOD ≤-1.28 for Strong, ≤-0.64 for Moderate, ≤-0.32 for Supporting based on non‐segregation." No non‐segregation data are available. Therefore, this criterion is not applied.

BP1

BP1 (Supporting)

According to VCEP guidelines, the rule for BP1 (Supporting) is: "Apply to all missense variants." D777N is a missense variant. Therefore, this criterion is applied at Supporting strength.

BP2

BP2 (Not Applied)

According to standard ACMG guidelines, the rule for BP2 is: "Observed in trans with a pathogenic variant for a fully penetrant dominant disorder." No such data exist. Therefore, this criterion is not applied.

BP3

BP3 (Not Applied)

According to standard ACMG guidelines, the rule for BP3 is: "In‐frame deletions/insertions in a repetitive region without a known function." This is a missense variant. Therefore, this criterion is not applied.

BP4

BP4 (Supporting)

According to VCEP guidelines, the rule for BP4 (Supporting) is: "RNA: At least one well‐established in silico predictor (e.g. SpliceAI) shows no impact on splicing." SpliceAI predicts no splice impact (max score 0.01). Therefore, this criterion is applied at Supporting strength.

BP5

BP5 (Not Applied)

According to standard ACMG guidelines, the rule for BP5 is: "Variant found in a case with an alternate molecular basis for disease." No such case information is available. Therefore, this criterion is not applied.

BP6

BP6 (Not Applied)

According to standard ACMG guidelines, the rule for BP6 is: "Reputable source reports variant as benign without available evidence." ClinVar submissions are conflicting and this rule is discouraged. Therefore, this criterion is not applied.

BP7

BP7 (Not Applied)

According to standard ACMG guidelines, the rule for BP7 is: "Synonymous and deep intronic variants with no predicted impact on splicing." This is a missense variant. Therefore, this criterion is not applied.