chr17-7674924-C-G

Position:

• chr17-7674924-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The ENST00000269305.9(TP53):​c.607G>C​(p.Val203Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Uncertain significancein ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V203M) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TP53 ENST00000269305.9 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 0.274

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 Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 5 benign, 16 uncertain in ENST00000269305.9
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TP53	NM_000546.6	c.607G>C	p.Val203Leu	missense_variant	6/11	ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.607G>C	p.Val203Leu	missense_variant	6/11	1	NM_000546.6	ENSP00000269305	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 17, 2023	The p.V203L variant (also known as c.607G>C), located in coding exon 5 of the TP53 gene, results from a G to C substitution at nucleotide position 607. The valine at codon 203 is replaced by leucine, an amino acid with highly similar properties. This variant is in the DNA binding domain of the TP53 protein and is reported to have partial 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 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 amino acid position is poorly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Li-Fraumeni syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 28, 2022

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 experimental studies (such as gene expression, population dynamics, functional pathways, and cell-cycle effects in cell culture) performed at Invitae indicates that this missense variant is expected to disrupt TP53 protein function. ClinVar contains an entry for this variant (Variation ID: 482235). This variant has not been reported in the literature in individuals affected with TP53-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 203 of the TP53 protein (p.Val203Leu). -

Li-Fraumeni syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Jun 18, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.74
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Benign	22
DANN	Benign	0.94
DEOGEN2	Uncertain	0.45	T;T;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.;T
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.61
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.51	D
MetaRNN	Uncertain	0.50	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.2	D
MutationAssessor	Benign	0.97	.;.;.;.;.;.;.;.;.;L;.;L;L;L;.;.;L;.;.;.;.
MutationTaster	Benign	0.82	N;N;N;N;N;N
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-1.0	N;N;.;.;.;.;.;.;.;N;.;.;N;N;.;.;N;.;.;N;N
REVEL	Uncertain	0.51
Sift	Uncertain	0.0010	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D
Sift4G	Uncertain	0.0040	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.
Polyphen		0.14	B;.;.;.;.;.;.;.;.;B;.;B;B;B;.;.;B;.;.;.;B
Vest4		0.30
MutPred		0.75		Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);.;.;.;.;.;.;.;Gain of sheet (P = 0.1208);.;Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);.;.;Gain of sheet (P = 0.1208);.;.;.;.;
MVP		0.90
MPC		0.64
ClinPred		0.22	T
GERP RS		3.4
Varity_R		0.83
gMVP		0.55

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs730882003; hg19: chr17-7578242;