17-7675238-T-C

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PM2 PP3_Strong PP5_Very_Strong

The NM_000546.6(TP53):c.376-2A>G variant causes a splice acceptor change. The variant was absent in control chromosomes in GnomAD project. 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:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TP53 NM_000546.6 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8 O:1
• Conservation: PhyloP100: 6.01

Genes affected

TP53 (HGNC:11998): (tumor protein p53) This gene encodes a tumor suppressor protein containing transcriptional activation, DNA binding, and oligomerization domains. The encoded protein responds to diverse cellular stresses to regulate expression of target genes, thereby inducing cell cycle arrest, apoptosis, senescence, DNA repair, or changes in metabolism. Mutations in this gene are associated with a variety of human cancers, including hereditary cancers such as Li-Fraumeni syndrome. Alternative splicing of this gene and the use of alternate promoters result in multiple transcript variants and isoforms. Additional isoforms have also been shown to result from the use of alternate translation initiation codons from identical transcript variants (PMIDs: 12032546, 20937277). [provided by RefSeq, Dec 2016]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-7675238-T-C is Pathogenic according to our data. Variant chr17-7675238-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 186236.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TP53	NM_000546.6	c.376-2A>G		splice_acceptor_variant		ENST00000269305.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TP53	ENST00000269305.9	c.376-2A>G		splice_acceptor_variant		1	NM_000546.6	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461636 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 727098

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Li-Fraumeni syndrome 1 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Feb 13, 2024	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. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -

Hereditary cancer-predisposing syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	May 22, 2023	The c.376-2A>G intronic variant results from an A to G substitution two nucleotides upstream from coding exon 4 in the TP53 gene. This alteration was identified once in a series of LFS families; however, clinical details were not provided (Wu CC et al. Hum. Genet., 2011 Jun;129:663-73). In addition, this alteration has been identified in individuals diagnosed with colorectal cancer, breast cancer, and B-CLL (Athanasakis E et al. Oncotarget, 2014 Dec;5:12635-45; Siraj AK et al. Hum. Genet., 2017 11;136:1431-1444; Li JY et al. Int. J. Cancer, 2019 01;144:281-289). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site and will result in the creation or strengthening of a novel splice acceptor site. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). 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. -

not provided Pathogenic:1 Other:1

not provided, no classification provided	in vitro	MutSpliceDB: a database of splice sites variants effects on splicing, NIH	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 18, 2022	Canonical splice site variant expected to result in aberrant splicing and demonstrated to result in an in-frame loss of seven amino acids (Chappuis 1999, Athanasakis 2014); Functional assays performed on tumor cells harboring this variant found reduced or absent transactivation of typical TP53 targets (Chappuis 1999, Athanasakis 2014, Agnoletto 2015); Observed in a kindred reported to have features of Li-Fraumeni syndrome and also identified in individuals with breast, colorectal, or ovarian cancer (Kupryjanczyk 1993, Wu 2011, Siraj 2017, Li 2019); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25525159, 21305319, 27189670, 10567903, 11595686, 24729566, 26857262, 25544776, 28497333, 8506342, 28975465, 15510160, 33790576, 29751042, 30720243, 29752822, 29070607, 25587027, 10864200) -

Li-Fraumeni syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Apr 26, 2023

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 186236). Disruption of this splice site has been observed in individual(s) with clinical features of Li-Fraumeni syndrome (PMID: 21305319, 25544776, 25587027, 29752822; Invitae). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This sequence change affects an acceptor splice site in intron 4 of the TP53 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in TP53 are known to be pathogenic (PMID: 20522432). -

Neoplasm of ovary Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne

Dec 01, 2018

- -

Gallbladder cancer Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

Institute of Medical Sciences, Banaras Hindu University

Oct 30, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.31
Cadd	Pathogenic	34
Dann	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D;D;D;D
GERP RS		4.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.91
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.96		Position offset: -23
DS_AL_spliceai		1.0		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs786202799; hg19: chr17-7578556; COSMIC: COSV52689235; COSMIC: COSV52689235;