rs587781702

Positions:

• chr17-7673609-C-A
• chr17-7673609-C-G
• chr17-7673609-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000546.6(TP53):​c.920-1G>T variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. 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 Pathogenic (★★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: TP53 NM_000546.6 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5 O:1
• Conservation: PhyloP100: 1.46

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 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.6, offset of 32, new splice context is: acaccagctcctctccccAGcca. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-7673609-C-A is Pathogenic according to our data. Variant chr17-7673609-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 480765.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TP53	NM_000546.6	c.920-1G>T		splice_acceptor_variant, intron_variant		ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.920-1G>T		splice_acceptor_variant, intron_variant		1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 06, 2017	The c.920-1G>T intronic pathogenic mutation results from a G to T substitution one nucleotide upstream from coding exon 8 of the TP53 gene. This altetation, designated as IVS8-1G>T, has been reported in a family that met Chompret criteria (Gonzalez KD et al. J. Med. Genet., 2009 Oct;46:689-93). This nucleotide position is highly conserved in available vertebrate species. Using the BDGP and ESEfinder splice site prediction tools, this alteration is predicted to abolish the native splice acceptor site; however, direct evidence is unavailable. 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 a disease-causing mutation. -

Li-Fraumeni syndrome 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Jun 18, 2022

- -

Li-Fraumeni syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 26, 2021

Variant summary: TP53 c.920-1G>T is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: 4/4 predict the variant abolishes a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251470 control chromosomes (gnomAD). c.920-1G>T has been reported in the literature in multiple families/individuals affected with tumors belonging to the Li-Fraumeni Syndrome tumor spectrum (e.g. Gonzalez_2009, Wu_2011, Rana_2019). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014, and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Ovarian neoplasm Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

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

Dec 01, 2018

- -

not provided Other:1

not provided, no classification provided

research

MutSpliceDB: a database of splice sites variants effects on splicing, NIH

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Benign	0.47	N
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.79
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.84		Position offset: -20
DS_AL_spliceai		1.0		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs587781702; hg19: chr17-7576927; COSMIC: COSV52664150; COSMIC: COSV52664150;