chr17-7674187-T-A

Position:

• chr17-7674187-T-A

Variant summary

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

The NM_000546.6(TP53):​c.776A>T​(p.Asp259Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,346 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:5
• Conservation: PhyloP100: 3.21

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 Uncertain_significance. Variant got 4 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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TP53	NM_000546.6	c.776A>T	p.Asp259Val	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.776A>T	p.Asp259Val	missense_variant	7/11	1	NM_000546.6	ENSP00000269305.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458346 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 725752

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: 9.02e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:5

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Li-Fraumeni syndrome 1 Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Apr 11, 2023	This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	May 02, 2018	- -

Hereditary cancer-predisposing syndrome Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jun 18, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 12, 2021	The p.D259V pathogenic mutation (also known as c.776A>T), located in coding exon 6 of the TP53 gene, results from an A to T substitution at nucleotide position 776. The aspartic acid at codon 259 is replaced by valine, an amino acid with highly 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 assays (IARC TP53 database; Kato S et al. Proc Natl Acad Sci USA. 2003 Jul 8;100(14):8424-9, Maurici D et al. Oncogene, 2001 Jun;20:3533-40; Campomenosi P et al. Oncogene, 2001 Jun;20:3573-9; Monti P et al. Oncogene, 2003 Aug;22:5252-60; Jordan JJ et al. Mol. Cancer Res., 2010 May;8:701-16). 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 highly conserved through mammals but not in all available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Li-Fraumeni syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 02, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with valine, which is neutral and non-polar, at codon 259 of the TP53 protein (p.Asp259Val). 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: 485034). 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: 12826609, 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	0.95
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.33
CADD	Uncertain	23
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.49	T;T;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D
M_CAP	Pathogenic	0.91	D
MetaRNN	Uncertain	0.69	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	.;.;.;.;.;.;.;.;.;M;.;M;M;M;.;.;M;.;.;.
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-0.16	N;N;.;.;.;.;.;.;.;N;.;.;N;N;.;.;N;.;.;N
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D
Sift4G	Uncertain	0.0020	D;D;T;T;T;T;T;T;T;D;T;D;D;D;T;T;D;T;D;T
Polyphen		0.96	P;.;.;.;.;.;.;.;.;P;.;P;P;P;.;.;P;.;.;.
Vest4		0.54
MutPred		0.57		Loss of disorder (P = 0.0433);Loss of disorder (P = 0.0433);.;.;.;.;.;.;.;Loss of disorder (P = 0.0433);.;Loss of disorder (P = 0.0433);Loss of disorder (P = 0.0433);Loss of disorder (P = 0.0433);.;.;Loss of disorder (P = 0.0433);.;.;.;
MVP		0.97
MPC		0.45
ClinPred		0.96	D
GERP RS		4.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.81
gMVP		0.62

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: rs745425759; hg19: chr17-7577505; COSMIC: COSV52679505; COSMIC: COSV52679505;