NM_000546.6:c.725G>T

Variant names:

• chr17-7674238-C-A
• rs121912655
• NM_000546.6:c.725G>T

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.725G>T​(p.Cys242Phe) 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. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1 O:1
• Conservation: PhyloP100: 7.91

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 17-7674238-C-A is Pathogenic according to our data. Variant chr17-7674238-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 376578.We mark this variant Likely_pathogenic, oryginal submissions are: {other=1, Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TP53	NM_000546.6	c.725G>T	p.Cys242Phe	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.725G>T	p.Cys242Phe	missense_variant	Exon 7 of 11	1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.84e-7 AC: 1 AN: 1461830 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727230

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 30

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1

Sep 13, 2023

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.C242F pathogenic mutation (also known as c.725G>T), located in coding exon 6 of the TP53 gene, results from a G to T substitution at nucleotide position 725. The cysteine at codon 242 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This alteration has been identified in an Indian breast/ovarian cancer cohort (Singh J et al. Breast Cancer Res. Treat., 2018 Jul;170:189-196). This alteration has been reported as a germline alteration and as a somatic alteration in various tumors by the IARC TP53 database (Bouaoun L et al. IARC TP53 database [version 20, July 2019]. Hum. Mutat. 2016 Sep;37:865-76). This alteration 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 are equivocal about this variant's ability to suppress cell growth (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). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Ovarian neoplasm Pathogenic:1

Dec 01, 2018

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

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Li-Fraumeni syndrome Uncertain:1

Sep 21, 2023

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 function (PMID: 12826609, 29979965). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 12826609, 29979965, 30224644) indicates that this missense variant is expected to disrupt TP53 function. ClinVar contains an entry for this variant (Variation ID: 376578). This missense change has been observed in individual(s) with breast or ovarian cancer (PMID: 29470806). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces cysteine, which is neutral and slightly polar, with phenylalanine, which is neutral and non-polar, at codon 242 of the TP53 protein (p.Cys242Phe). -

Neoplasm Other:1

Mar 04, 2025

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Significance: -

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D;D;.;.;.;.;D;D;.;D;.;.;.;.;.;.;D;.;.;.;D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.81
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	0.74	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	Uncertain	0.78	T
PROVEAN	Pathogenic	-10	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D
REVEL	Pathogenic	0.98
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		0.97
MutPred		0.97		Loss of stability (P = 0.0461);Loss of stability (P = 0.0461);.;.;.;.;.;.;.;Loss of stability (P = 0.0461);.;Loss of stability (P = 0.0461);Loss of stability (P = 0.0461);Loss of stability (P = 0.0461);.;.;Loss of stability (P = 0.0461);.;.;.;.;
MVP		0.99
MPC		0.47
ClinPred		1.0	D
GERP RS		4.6
Varity_R		1.0
gMVP		0.91

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: rs121912655; hg19: chr17-7577556; COSMIC: COSV52677418; COSMIC: COSV52677418;