16-23635138-T-C
Variant summary
Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong
The NM_024675.4(PALB2):āc.1408A>Gā(p.Thr470Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000681 in 1,614,238 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_024675.4 missense
Scores
Clinical Significance
Conservation
Publications
- hereditary breast carcinomaInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
- Fanconi anemia complementation group NInheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
- pancreatic cancer, susceptibility to, 3Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- familial ovarian cancerInheritance: AD Classification: MODERATE Submitted by: ClinGen
- Fanconi anemiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- hereditary nonpolyposis colon cancerInheritance: AD Classification: LIMITED Submitted by: ClinGen
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -4 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| PALB2 | NM_024675.4 | c.1408A>G | p.Thr470Ala | missense_variant | Exon 4 of 13 | ENST00000261584.9 | NP_078951.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| PALB2 | ENST00000261584.9 | c.1408A>G | p.Thr470Ala | missense_variant | Exon 4 of 13 | 1 | NM_024675.4 | ENSP00000261584.4 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152236Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.0000119 AC: 3AN: 251132 AF XY: 0.00000737 show subpopulations
GnomAD4 exome AF: 0.00000684 AC: 10AN: 1461884Hom.: 0 Cov.: 32 AF XY: 0.00000688 AC XY: 5AN XY: 727240 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000656 AC: 1AN: 152354Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74506 show subpopulations ā ļø The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
ClinVar
Submissions by phenotype
not specified Uncertain:2
Variant summary: PALB2 c.1408A>G (p.Thr470Ala) 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 1.2e-05 in 251132 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1408A>G has been reported in the literature in individuals affected with breast cancer and Wilms tumor, without strong evidence of causality (Pedro_2020, Doddato_2021, Ciceri_2018). These reports do not provide unequivocal conclusions about association of the variant with Breast Cancer. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
- -
not provided Uncertain:2
The PALB2 c.1408A>G (p.Thr470Ala) variant has been reported in the published literature in individuals with breast cancer (PMID: 35534704 (2022)), suspected hereditary breast/ovarian cancer (PMIDs: 35980532 (2022), 34026625 (2021)), gastric cancer (PMID: 34326862 (2021)), and Wilms tumor (PMID: 30344923 (2018)). It has also been identified in an individual affected with thyroid cancer, breast cancer, and cervical paraganglioma (PMID: 32408270 (2020)). In a case-control study, this variant was observed in 3 individuals with breast cancer and in 3 reportedly healthy individuals (PMID: 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/)). The frequency of this variant in the general population, 0.000012 (3/251132 chromosomes (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. -
This variant is denoted PALB2 c.1408A>G at the cDNA level, p.Thr470Ala (T470A) at the protein level, and results in the change of a Threonine to an Alanine (ACA>GCA). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. PALB2 Thr470Ala was not observed at a significant allele frequency in large population cohorts (Lek 2016). PALB2 Thr470Ala is not located in a known functional domain. In-silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function. Based on currently available evidence, it is unclear whether PALB2 Thr470Ala is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -
Familial cancer of breast Uncertain:1Benign:1
This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 470 of the PALB2 protein (p.Thr470Ala). This variant is present in population databases (rs150636811, gnomAD 0.003%). This missense change has been observed in individual(s) with Wilms tumor, paraganglioma, breast cancer, and thyroid cancer (PMID: 30344923, 32408270, 34026625, 34326862, 35534704, 35980532). ClinVar contains an entry for this variant (Variation ID: 185197). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt PALB2 protein function with a negative predictive value of 80%. 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. -
- -
Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
This missense variant replaces threonine with alanine at codon 470 of the PALB2 protein. Computational prediction suggests that this variant may not impact protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with breast cancer and an individual affected with breast, ovarian or pancreatic cancer (PMID: 32408270, 34026625) and a breast cancer case-control meta-analysis has reported this variant in 3/60466 cases and 3/53461 unaffected individuals (PMID: 33471991; Leiden Open Variation Database DB-ID PALB2_011035). This variant also has been reported in an individual affected with Wilm's tumor (PMID: 30344923). This variant has been identified in 3/251132 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. -
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Inherited breast cancer and ovarian cancer Uncertain:1
BP1 -
Breast-ovarian cancer, familial, susceptibility to, 5 Uncertain:1
- -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at