16-23614003-C-G
Variant summary
Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_024675.4(PALB2):c.3201+1G>C variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.000000686 in 1,457,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).
Frequency
Consequence
NM_024675.4 splice_donor, intron
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Pathogenic. Variant got 18 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 exome AF: 6.86e-7 AC: 1AN: 1457000Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1AN XY: 725110
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Familial cancer of breast Pathogenic:4
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Curators: Marc Tischkowitz, Arleen D. Auerbach. Submitter to LOVD: Marc Tischkowitz. -
This sequence change affects a donor splice site in intron 11 of the PALB2 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and may result in an absent or altered protein product. This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with clinical features of PALB2-related conditions (PMID: 22241545, 25099575, 28888541, 29753700, 32081490). This variant is also known as c.3202+1G>C. ClinVar contains an entry for this variant (Variation ID: 143972). Studies have shown that disruption of this splice site alters mRNA splicing and is expected to lead to the loss of protein expression (PMID: 34846068; internal data). For these reasons, this variant has been classified as Pathogenic. -
This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -
not provided Pathogenic:3
The variant disrupts a canonical splice site, and is therefore predicted to result in the loss of a functional protein. Found in at least one patient with expected phenotype for this gene, and not found in general population data. -
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Canonical splice site variant predicted to result in a null allele in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Observed in individuals with bilateral breast cancer, ovarian cancer, and other cancers (PMID: 28888541, 22241545, 25099575, 32081490); This variant is associated with the following publications: (PMID: 23935381, 22241545, 25099575, 28152038, 32081490, 29753700, 30890586, 36497448, 28888541) -
Hereditary cancer-predisposing syndrome Pathogenic:3
This variant causes a G>C nucleotide substitution at the +1 position of intron 11 of the PALB2 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although this prediction has not been confirmed in published RNA studies, this variant is expected to result in an absent or disrupted protein product. This variant has been reported in individuals affected with breast cancer (PMID: 22241545, 23935381) and gastric cancer (PMID: 28024868). Additionally, this variant has been reported in individuals affected with medulloblastoma, uveal melanoma and renal cell carcinoma (PMID: 29753700, 32081490). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of PALB2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Likely Pathogenic. -
The c.3201+1G>C intronic variant results from a G to C substitution one nucleotide after coding exon 11 of the PALB2 gene. This alteration has been detected as germline in multiple families with hereditary breast cancer (Tischkowitz M et al. Hum. Mutat., 2012 Apr;33:674-80; Antoniou AC et al. N. Engl. J. Med., 2014 Aug;371:497-506). This variant was also identified as germline in a 5 year old with medulloblastoma whose tumor demonstrated loss of heterozygosity (Waszak SM et al. Lancet Oncol, 2018 06;19:785-798). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -
The PALB2 c.3201+1G>C variant occurs in a canonical splice site (donor) and is therefore predicted to disrupt or distort the normal gene product. This variant, also referred to as c.3202+1G>C, has been reported in a heterozygous state in one individual with contralateral breast cancer (Tischkowitz et al. 2012). In addition, a variant at the same position, but with a different nucleotide change (c.3201+1G>T) was detected in a heterozygous state in an individual with hereditary diffuse gastric cancer (Sahasrabudhe et al. 2017). Family histories of the respective cancers were also reported for both individuals in first- and/or second- degree relatives (Tischkowitz et al. 2012; Sahasrabudhe et al. 2017). This variant is not observed at a significant frequency in version 4.0.0 of the Genome Aggregation Database. Based on the evidence he c.3201+1G>C variant is classified as pathogenic for PALB2-related disorders. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at