rs1555525353

Variant names:

• chr17-7673829-A-G
• rs1555525353
• NM_000546.6:c.791T>C

Your query was ambiguous. Multiple possible variants found:

• chr17-7673829-A-G
• chr17-7673829-A-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000546.6(TP53):​c.791T>C​(p.Leu264Pro) 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L264I) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 9.32
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• breast cancer

  Inheritance: AD Classification: DEFINITIVE Submitted by: Ambry Genetics
• Li-Fraumeni syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet
• Li-Fraumeni syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp
• adrenocortical carcinoma, hereditary

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• sarcoma

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• bone marrow failure syndrome 5

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• colorectal cancer

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• choroid plexus carcinoma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 35 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 34 uncertain in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.966

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TP53	NM_000546.6	c.791T>C	p.Leu264Pro	missense_variant	Exon 8 of 11	ENST00000269305.9	NP_000537.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TP53	ENST00000269305.9	c.791T>C	p.Leu264Pro	missense_variant	Exon 8 of 11	1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Dec 12, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L264P variant (also known as c.791T>C), located in coding exon 7 of the TP53 gene, results from a T to C substitution at nucleotide position 791. The leucine at codon 264 is replaced by proline, an amino acid with some similar properties. This alteration has been reported as a somatic mutation one time in a larynx tumor, but not as a germline mutation by the IARC TP53 database. This variant is in the DNA binding domain of the TP53 protein and was found to not have an effect on transactivation capacity in yeast based assays (Petitjean A et al. IARC TP53 database [version R17, November 2013]. Hum Mutat. 2007 Jun;28(6):622-9; Kato S et al. Proc Natl Acad Sci USA. 2003 Jul 8;100(14):8424-9). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Jun 18, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Li-Fraumeni syndrome 1 Uncertain:1

Jun 18, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Li-Fraumeni syndrome Uncertain:1

Jan 27, 2022

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 does not substantially affect 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 not expected to disrupt TP53 protein function. ClinVar contains an entry for this variant (Variation ID: 480759). 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 leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 264 of the TP53 protein (p.Leu264Pro).

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.70	D;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.
Eigen	Uncertain	0.23
Eigen_PC	Uncertain	0.25
LIST_S2	Benign	0.75	T;T;T;T;T;T;T;.;.;.;T;T;.;T;T;T;T;T;T
M_CAP	Pathogenic	0.56	D
MetaRNN	Pathogenic	0.97	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Benign	0.0	.;.;.;.;.;.;.;.;M;.;M;M;M;.;.;M;.;.;.
PhyloP100		9.3
PrimateAI	Benign	0.48	T
PROVEAN	Uncertain	-4.1	D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
Sift	Uncertain	0.0010	D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
Sift4G	Uncertain	0.0020	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
Vest4		0.72
ClinPred		0.99	D
GERP RS		5.1
PromoterAI		-0.014	Neutral
Varity_R		0.96
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

Other links and lift over

dbSNP: rs1555525353; hg19: chr17-7577147; COSMIC: COSV53470181;