rs763937788
Variant summary
Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_024675.4(PALB2):c.2028T>G(p.Ile676Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,614,046 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I676T) has been classified as Benign.
Frequency
Consequence
NM_024675.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Uncertain_significance. Variant got 0 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152174Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.00000398 AC: 1AN: 251442Hom.: 0 AF XY: 0.00 AC XY: 0AN XY: 135898
GnomAD4 exome AF: 6.84e-7 AC: 1AN: 1461872Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 727238
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152174Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74352
ClinVar
Submissions by phenotype
Familial cancer of breast Uncertain:2
This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 676 of the PALB2 protein (p.Ile676Met). This variant is present in population databases (rs763937788, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with PALB2-related conditions. ClinVar contains an entry for this variant (Variation ID: 410134). 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. -
The PALB2 c.2028T>G (p.Ile676Met) missense change has a maximum subpopulation frequency of 0.0028% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL predicts a benign effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. To our knowledge, this variant has not been reported in individuals with PALB2-associated conditions. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
Hereditary cancer-predisposing syndrome Uncertain:1
The p.I676M variant (also known as c.2028T>G), located in coding exon 5 of the PALB2 gene, results from a T to G substitution at nucleotide position 2028. The isoleucine at codon 676 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is not well conserved in available 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. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at