17-7674218-T-C

Position:

• chr17-7674218-T-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.745A>G​(p.Arg249Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,690 control chromosomes in the GnomAD database, with no homozygous occurrence. 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.)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4 U:3
• Conservation: PhyloP100: 0.128

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]

TP53 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a region_of_interest Interaction with AXIN1 (size 176) in uniprot entity P53_HUMAN there are 53 pathogenic changes around while only 3 benign (95%) in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99
• PP5: Variant 17-7674218-T-C is Pathogenic according to our data. Variant chr17-7674218-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 376654.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=3, Pathogenic=1, Likely_pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TP53	NM_000546.6	c.745A>G	p.Arg249Gly	missense_variant	7/11	ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.745A>G	p.Arg249Gly	missense_variant	7/11	1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461690 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727156

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:4 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Li-Fraumeni syndrome 1 Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Feb 16, 2024	This variant is considered likely pathogenic. Functional studies indicate this variant impacts protein function [PMID: 23246812, 29979965]. This variant is expected to disrupt protein structure [Myriad internal data]. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 02, 2023	The p.R249G pathogenic mutation (also known as c.745A>G), located in coding exon 6 of the TP53 gene, results from an A to G substitution at nucleotide position 745. The arginine at codon 249 is replaced by glycine, an amino acid with dissimilar properties. This variant is in the DNA binding domain of the TP53 protein and is reported to have loss of transactivation capacity in yeast based functional 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 and has a dominant negative effect (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, as well as other alterations at codon 249, have been observed numerous times somatically in the cancerhotspots.org database (Chang MT et al. Cancer Discov. 2018 02;8:174-183), however germline observations have not been reported. This variant has been detected in at least one individual at an allele fraction that is suggestive of clonal hematopoiesis, a predictor of TP53 pathogenicity (Ambry internal data; Fortuno C et al. Genet Med. 2022 03;24:673-680). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -

not provided Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

Mayo Clinic Laboratories, Mayo Clinic

-

- -

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

- -

Li-Fraumeni syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 27, 2024

This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 249 of the TP53 protein (p.Arg249Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TP53-related conditions. ClinVar contains an entry for this variant (Variation ID: 376654). 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 with a positive predictive value of 97.5%. Experimental studies have shown that this missense change affects TP53 function (PMID: 12826609, 23246812, 26271412, 29979965, 30224644). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D;D;.;.;.;.;D;D;.;D;.;.;.;.;.;.;D;.;.;.
Eigen	Benign	-0.062
Eigen_PC	Benign	-0.26
FATHMM_MKL	Benign	0.41	N
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D
M_CAP	Pathogenic	0.78	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
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.3	.;.;.;.;.;.;.;.;.;M;.;M;M;M;.;.;M;.;.;.
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-6.2	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
REVEL	Pathogenic	0.89
Sift	Uncertain	0.0010	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;.;.;.
Vest4		0.97
MutPred		0.96		Loss of stability (P = 0.0171);Loss of stability (P = 0.0171);.;.;.;.;.;.;.;Loss of stability (P = 0.0171);.;Loss of stability (P = 0.0171);Loss of stability (P = 0.0171);Loss of stability (P = 0.0171);.;.;Loss of stability (P = 0.0171);.;.;.;
MVP		1.0
MPC		0.43
ClinPred		1.0	D
GERP RS		-0.023
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: rs587782082; hg19: chr17-7577536; COSMIC: COSV52676356; COSMIC: COSV52676356;