rs763098116

chr17-7673790-C-Achr17-7673790-C-Gchr17-7673790-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_000546.6(TP53):c.830G>T(p.Cys277Phe) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,856 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C277R) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:3
• Conservation: PhyloP100: 6.08

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 11 ACMG points.

• PM1: In a hotspot region, there are 17 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 16 uncertain in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-7673791-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 421804.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Likely_pathogenic=3}.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 17-7673790-C-A is Pathogenic according to our data. Variant chr17-7673790-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 458567.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=3, Likely_pathogenic=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TP53	NM_000546.6	c.830G>T	p.Cys277Phe	missense_variant	8/11	ENST00000269305.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TP53	ENST00000269305.9	c.830G>T	p.Cys277Phe	missense_variant	8/11	1	NM_000546.6	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251308 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135834

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461856 Hom.: 0 Cov.: 33 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.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Li-Fraumeni syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Mar 04, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Oct 13, 2023	This sequence change replaces cysteine, which is neutral and slightly polar, with phenylalanine, which is neutral and non-polar, at codon 277 of the TP53 protein (p.Cys277Phe). This variant is present in population databases (rs763098116, gnomAD 0.0009%). 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: 458567). 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. Experimental studies have shown that this missense change affects TP53 function (PMID: 9407971, 12826609, 19850740, 26070072, 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. -

Li-Fraumeni syndrome 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Feb 20, 2024

This variant is considered likely pathogenic. Functional studies indicate this variant impacts protein function [PMID: 18524770, 27813088, 29979965]. This variant is expected to disrupt protein structure [Myriad internal data]. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 23, 2023

The p.C277F variant (also known as c.830G>T), located in coding exon 7 of the TP53 gene, results from a G to T substitution at nucleotide position 830. The cysteine at codon 277 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This alteration has been shown to have a loss of transactivation activity in yeast based functional studies (IARC TP53 database: Kato S et al. Proc. Natl. Acad. Sci. U.S.A., 2003 Jul;100:8424-9; Kucab JE et al. DNA Repair (Amst.), 2016 Mar;39:21-33; Paget V et al. PLoS ONE, 2012 Feb;7:e30921). 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). Another alteration at the same codon, p.C277R (c.829T>C), has been detected an individual with a personal history of adrenocortical carcinoma and shown to segregate with disease in three affected family members in one family with early-onset breast cancer tested by our laboratory (Ambry internal data). This amino acid position is well conserved in available vertebrate species. The p.C277F alteration has been observed numerous times as a somatic mutation in the cancerhotspots.org database (Chang MT et al. Cancer Discov. 2018 02;8:174-183). 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 variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD) non-cancer dataset. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

TP53-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Jun 23, 2023

The TP53 c.830G>T variant is predicted to result in the amino acid substitution p.Cys277Phe. To our knowledge, this variant has not been reported in the literature in association with TP53-related disease. Functional studies in vitro indicate that this variant affects protein function (see for example, Kato et al. 2003. PubMed ID: 12826609; Malcikova et al. 2009. PubMed ID: 19850740; Giacomelli AO et al. 2018. PMID: 30224644). This variant is reported in 0.00088% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/17-7577108-C-A). In ClinVar, it is classified as a variant of uncertain significance (https://www.ncbi.nlm.nih.gov/clinvar/variation/458567/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
Cadd	Pathogenic	28
Dann	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D
M_CAP	Pathogenic	0.52	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.93	D
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-10	D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
Polyphen		1.0, 1.0	.;.;.;.;.;.;.;.;D;.;D;D;D;.;.;D;.;.;.
Vest4		0.92
MutPred		0.94		Loss of sheet (P = 0.1158);.;.;.;.;.;.;.;Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);.;.;Loss of sheet (P = 0.1158);.;.;.;
MVP		0.99
MPC		0.44
ClinPred		1.0	D
GERP RS		5.1
Varity_R		1.0
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs763098116; hg19: chr17-7577108; COSMIC: COSV52693726; COSMIC: COSV52693726;