17-7674239-A-G

Variant names:

• chr17-7674239-A-G
• rs1057519982
• NM_000546.6:c.724T>C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000546.6(TP53):​c.724T>C​(p.Cys242Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 31)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4 U:1
• Conservation: PhyloP100: 9.32

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 Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a region_of_interest Interaction with the 53BP2 SH3 domain (size 7) in uniprot entity P53_HUMAN there are 9 pathogenic changes around while only 0 benign (100%) in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 17-7674239-A-G is Pathogenic according to our data. Variant chr17-7674239-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 449512.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1, Pathogenic=3}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TP53	NM_000546.6	c.724T>C	p.Cys242Arg	missense_variant	Exon 7 of 11	ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.724T>C	p.Cys242Arg	missense_variant	Exon 7 of 11	1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:2

Apr 22, 2022

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published functional studies demonstrate a damaging effect: non-functional transactivation and impaired growth suppression ability (Kato 2003, Kotler 2018); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 30840781, 19367287, 20581117, 20805372, 12209590, 24550057, 17947339, 23772609, 18511570, 25896519, 29979965, 15541116, 34099734, 15510160, Sasa_2022, 21059199) -

Nov 03, 2021

Institute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU Dresden

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Li-Fraumeni syndrome 1 Pathogenic:1

Feb 16, 2024

Myriad Genetics, Inc.

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely pathogenic. Functional studies indicate this variant impacts protein function [PMID: 29979965]. This variant is expected to disrupt protein structure [Myriad internal data]. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Feb 20, 2020

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.C242R pathogenic mutation (also known as c.724T>C), located in coding exon 6 of the TP53 gene, results from a T to C substitution at nucleotide position 724. The cysteine at codon 242 is replaced by arginine, an amino acid with highly dissimilar properties. This pathogenic mutation has been reported in multiple early onset breast cancer patients including one woman who was diagnosed with phyllodes breast tumor at age 22, liposarcoma at age 26, contralateral breat cancer at age 29 and ipsilateral recurrence within the radiation field at age 33, and chest wall angiosarcoma at age 35 (Wilson JR et al. J. Med. Genet. 2010 Nov;47:771-4; Heymann S et al. Radiat Oncol. 2010 Nov;5:104). This variant is in the DNA binding domain of the TP53 protein and is reported to have loss of transactivation in yeast based assays (IARC TP53 database: Kato S et al. Proc. Natl. Acad. Sci. USA 2003 Jul;100:8424-9). Studies conducted in human cell lines indicate this alteration is deficient at growth suppression (Kotler E et al. Mol. Cell. 2018 Jul;71:178-190.e8; Giacomelli AO et al. Nat. Genet. 2018 Oct;50:1381-1387). This alteration is located in the functionally critical DNA binding domain, and it is one of four amino acid residues required for zinc binding and protein stabilization (Cho Y et al. Science. 1994 Jul;265:346-55). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Li-Fraumeni syndrome Uncertain:1

Jul 30, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Experimental studies have shown that this missense change affects TP53 protein function (PMID: 12826609, 29979965, 30224644). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TP53 protein function. ClinVar contains an entry for this variant (Variation ID: 449512). This missense change has been observed in individual(s) with clinical features of Li-Fraumeni syndrome (PMID: 18511570, 20805372, 21059199, 25896519). This variant is not present in population databases (ExAC no frequency). This sequence change replaces cysteine with arginine at codon 242 of the TP53 protein (p.Cys242Arg). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D;D;.;.;.;.;D;D;.;D;.;.;.;.;.;.;D;.;.;.;D
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.85	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Pathogenic	3.3	.;.;.;.;.;.;.;.;.;M;.;M;M;M;.;.;M;.;.;.;.
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-11	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.
Polyphen		1.0	D;.;.;.;.;.;.;.;.;D;.;D;D;D;.;.;D;.;.;.;D
Vest4		0.98
MutPred		0.96		Loss of stability (P = 0.0076);Loss of stability (P = 0.0076);.;.;.;.;.;.;.;Loss of stability (P = 0.0076);.;Loss of stability (P = 0.0076);Loss of stability (P = 0.0076);Loss of stability (P = 0.0076);.;.;Loss of stability (P = 0.0076);.;.;.;.;
MVP		0.99
MPC		0.50
ClinPred		1.0	D
GERP RS		4.6
Varity_R		0.99
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1057519982; hg19: chr17-7577557; COSMIC: COSV52660956; COSMIC: COSV52660956;