chr16-23638081-C-G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP6

The NM_024675.4(PALB2):​c.97G>C​(p.Ala33Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,666 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. A33D) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PALB2
NM_024675.4 missense

Scores

2
12
5

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: 1.64

Publications

3 publications found
Variant links:
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]
PALB2 Gene-Disease associations (from GenCC):
  • hereditary breast carcinoma
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
  • Fanconi anemia complementation group N
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
  • pancreatic cancer, susceptibility to, 3
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • familial ovarian cancer
    Inheritance: AD Classification: MODERATE Submitted by: ClinGen
  • Fanconi anemia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hereditary nonpolyposis colon cancer
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP6
Variant 16-23638081-C-G is Benign according to our data. Variant chr16-23638081-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 569340.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PALB2NM_024675.4 linkc.97G>C p.Ala33Pro missense_variant Exon 2 of 13 ENST00000261584.9 NP_078951.2 Q86YC2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PALB2ENST00000261584.9 linkc.97G>C p.Ala33Pro missense_variant Exon 2 of 13 1 NM_024675.4 ENSP00000261584.4 Q86YC2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461666
Hom.:
0
Cov.:
30
AF XY:
0.00
AC XY:
0
AN XY:
727142
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111806
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Familial cancer of breast Uncertain:1
Dec 21, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 569340). 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 alanine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 33 of the PALB2 protein (p.Ala33Pro). -

Hereditary breast ovarian cancer syndrome Benign:1
Jan 08, 2024
German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:curation

BP1; BP4; PM2_sup; BS2_sup. According to the ACMG standard criteria we chose these criteria: PM2 (supporting pathogenic): Absent from gnomAD, BP1 (supporting benign): True missense pathogenic variants in PALB2 are not yet confirmed or refuted but are thought to be exceedingly rare, BP4 (supporting benign): Splice prediction benign , BS3 (supporting benign): Own RNA-Analysis (blood derived RNA) revealed biallelic expression of variant in WT-transcript -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.16
D
BayesDel_noAF
Uncertain
-0.010
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.45
T;T
Eigen
Uncertain
0.67
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.86
D;T
M_CAP
Benign
0.024
T
MetaRNN
Uncertain
0.48
T;T
MetaSVM
Benign
-0.82
T
MutationAssessor
Uncertain
2.8
M;.
PhyloP100
1.6
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-3.1
D;.
REVEL
Benign
0.18
Sift
Uncertain
0.010
D;.
Sift4G
Uncertain
0.013
D;.
Polyphen
1.0
D;.
Vest4
0.61
MutPred
0.27
Gain of relative solvent accessibility (P = 0.0479);.;
MVP
0.88
MPC
0.38
ClinPred
0.99
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.77
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

Other links and lift over

dbSNP: rs747302288; hg19: chr16-23649402; API