chr17-7675125-A-C

Position:

• chr17-7675125-A-C

Variant summary

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

The ENST00000269305.9(TP53):​c.487T>G​(p.Tyr163Asp) 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y163C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TP53 ENST00000269305.9 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 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 Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 17 uncertain in ENST00000269305.9
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-7675124-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 127814.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 17-7675125-A-C is Pathogenic according to our data. Variant chr17-7675125-A-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 187052.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TP53	NM_000546.6	c.487T>G	p.Tyr163Asp	missense_variant	5/11	ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.487T>G	p.Tyr163Asp	missense_variant	5/11	1	NM_000546.6	ENSP00000269305	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 20, 2019

The p.Y163D variant (also known as c.487T>G), located in coding exon 4 of the TP53 gene, results from a T to G substitution at nucleotide position 487. The tyrosine at codon 163 is replaced by aspartic acid, an amino acid with highly dissimilar properties. This alteration is located in the DNA binding domain and has been shown to be non-functional in yeast-based functional studies (Kato, S et al. Proc Natl Acad Sci U S A. 2003 Jul 8;100(14):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). Another alteration at this same location, p.Y163C, has been identified in two different Li-Fraumeni families. The proband in each case had multiple primary childhood cancers; all in the LFS spectrum of cancers. (Villani et. al., Lancet Oncology. 2011; 12: 559; McIntyre JF, J. Clin. Oncol. 1994 May; 12(5):925-30). Additionally, structural analysis had indicated that the Y163C alteration results in altered fold stability and would influence both DNA binding and tetramerization (internal analysis). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is well conserved in available vertebrate species. 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. -

Li-Fraumeni syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 18, 2021

This sequence change replaces tyrosine with aspartic acid at codon 163 of the TP53 protein (p.Tyr163Asp). The tyrosine residue is highly conserved and there is a large physicochemical difference between tyrosine and aspartic acid. 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, 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: 187052). This variant has not been reported in the literature in individuals affected with TP53-related conditions. This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Uncertain	25
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.87	D;D;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.;D;D
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.85	T;T;D;D;D;D;D;D;.;.;.;T;D;.;D;D;T;T;D;D;D;D
M_CAP	Pathogenic	0.71	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;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	3.2	.;.;.;.;.;.;.;.;.;M;.;M;M;M;.;.;M;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-9.7	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D;D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D;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		0.89
MutPred		0.88		Gain of disorder (P = 0.0062);Gain of disorder (P = 0.0062);.;.;.;.;.;.;.;Gain of disorder (P = 0.0062);.;Gain of disorder (P = 0.0062);Gain of disorder (P = 0.0062);Gain of disorder (P = 0.0062);.;.;Gain of disorder (P = 0.0062);.;.;.;.;Gain of disorder (P = 0.0062);
MVP		0.99
MPC		2.2
ClinPred		1.0	D
GERP RS		4.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.99
gMVP		0.88

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: rs786203436; hg19: chr17-7578443; COSMIC: COSV52853225; COSMIC: COSV52853225;