17-7674861-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_000546.6(TP53):c.670G>A(p.Glu224Lys) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. E224A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TP53 NM_000546.6 missense, splice_region
• Scores: Splicing: ADA: 0.1173
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 4.16

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 5 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 14 uncertain in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.755

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TP53	NM_000546.6	c.670G>A	p.Glu224Lys	missense_variant, splice_region_variant	6/11	ENST00000269305.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TP53	ENST00000269305.9	c.670G>A	p.Glu224Lys	missense_variant, splice_region_variant	6/11	1	NM_000546.6	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

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	Dec 18, 2018	The p.E224K variant (also known as c.670G>A), located in coding exon 5 of the TP53 gene, results from a G to A substitution at nucleotide position 670. The glutamic acid at codon 224 is replaced by lysine, an amino acid with similar properties. This variant is in the DNA binding domain of the TP53 protein and is reported to have decreased transactivation capacity compared to wild type, but no dominant negative effect in yeast based assays (IARC TP53 database; Kato S et al. Proc. Natl. Acad. Sci. USA. 2003 Jul;100:8424-9; Monti P et al. Oncogene, 2002 Mar;21:1641-8).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. 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

Invitae

Nov 04, 2021

This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 224 of the TP53 protein (p.Glu224Lys). Experimental studies have shown that this missense change does not substantially affect 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C15"). ClinVar contains an entry for this variant (Variation ID: 480767). 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). -

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	0.91
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.20
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.47	T;T;.;.;.;.;T;T;.;D;.;.;.;.;.;.;D;.;.;.;D
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D;D;.;.;.;D;D;.;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.76	D;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
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-1.5	N;N;.;.;.;.;.;.;.;N;.;.;N;N;.;.;N;.;.;N;N
REVEL	Pathogenic	0.70
Sift	Uncertain	0.0010	D;D;.;.;.;.;.;.;.;D;.;.;D;D;.;.;D;.;.;D;D
Sift4G	Uncertain	0.0050	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.
Polyphen		0.92	P;.;.;.;.;.;.;.;.;P;.;P;B;P;.;.;P;.;.;.;B
Vest4		0.65
MutPred		0.60		Gain of methylation at E224 (P = 0.0039);Gain of methylation at E224 (P = 0.0039);.;.;.;.;.;.;.;Gain of methylation at E224 (P = 0.0039);.;Gain of methylation at E224 (P = 0.0039);Gain of methylation at E224 (P = 0.0039);Gain of methylation at E224 (P = 0.0039);.;.;Gain of methylation at E224 (P = 0.0039);.;.;.;.;
MVP		0.89
MPC		1.6
ClinPred		0.98	D
GERP RS		3.1
Varity_R		0.87
gMVP		0.38

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.12
dbscSNV1_RF	Benign	0.57
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: rs1555525707; hg19: chr17-7578179; COSMIC: COSV52760587; COSMIC: COSV52760587;