rs121912662

chr17-7670678-A-Gchr17-7670678-A-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000546.6(TP53):c.1031T>C(p.Leu344Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,826 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L344V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TP53 NM_000546.6 missense
• Clinical Significance: Likely pathogenic reviewed by expert panel P:6
• Conservation: PhyloP100: 8.18

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 16 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 10 benign, 15 uncertain in NM_000546.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989
• PP5: Variant 17-7670678-A-G is Pathogenic according to our data. Variant chr17-7670678-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 12375.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TP53	NM_000546.6	c.1031T>C	p.Leu344Pro	missense_variant	10/11	ENST00000269305.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TP53	ENST00000269305.9	c.1031T>C	p.Leu344Pro	missense_variant	10/11	1	NM_000546.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461826 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727208

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:6

Revision: reviewed by expert panel

Submissions by phenotype

Li-Fraumeni syndrome 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Feb 21, 2024	This variant is considered pathogenic. Functional studies indicate this variant impacts protein function [PMID: 9704930, 9704931, 27754743]. This variant is expected to disrupt protein structure [Myriad internal data]. This variant has been reported in multiple individuals with clinical features of gene-specific disease [PMID: 8649785]. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Oct 01, 1999	- -

Li-Fraumeni syndrome Pathogenic:1

Likely pathogenic, reviewed by expert panel

curation

ClinGen TP53 Variant Curation Expert Panel, ClinGen

Aug 28, 2019

This variant is absent in the gnomAD cohort (PM2_Supporting; http://gnomad.broadinstitute.org). This variant has a BayesDel score > 0.16 and Align GVGD (Zebrafish) is Class 65 (PP3_Moderate). Additionally, transactivation assays show a low functioning allele according to Kato, et al. and there is a tetramerization assay demonstrating a mutant protein that only forms dimers (PS3; PMID: 12826609, PMID: 9704930). This variant has been reported in 2 probands meeting classic LI-FRAUMENI SYNDROME criteria (PS4_Moderate; PMID: 8649785, 20522432). In summary, TP53 c.1031T>C; p.Leu344Pro meets criteria to be classified as likely pathogenic for Li-Fraumeni syndrome. ACMG/AMP criteria applied, as specified by the TP53 Variant Curation Expert Panel: PM2_Supporting, PP3_Moderate, PS3, PS4_Moderate. -

Adrenocortical carcinoma, hereditary Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Jun 13, 2021

- -

Adrenal cortex carcinoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

Key Laboratory of Carcinogenesis and Cancer Invasion, Central South University

-

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 10, 2015

The p.L344P pathogenic mutation (also known as c.1031T>C), located in coding exon 9 of the TP53 gene, results from a T to C substitution at nucleotide position 1031. The leucine at codon 344 is replaced by proline, an amino acid with some similar properties. This alteration occurs at a well-characterized residue involved in the tetramerization of the p53 protein (Mateu and Fersht, EMBO J. 1998 May; 17(10):2748-58). This alteration has been identified in families meeting clinical criteria for Li-Fraumeni syndrome with a tumor spectrum including osteosarcomas, leiomyosarcomas, and early onset breast cancer (Petitjean A et al. IARC TP53 database [version R17, November 2013]. Hum Mutat. 2007 Jun;28(6):622-9;Varley J et al., Oncogene 1996 Jun; 12(11):2437-42 ). Evidence from both functional and structural analyses indicate that this alteration is structurally unstable and unable to form tetramers (Ishioka C et al., Oncogene 1995 Apr; 10(8):1485-92; Davison T et al., Oncogene 1998 Aug; 17(5):651-6). Additional functional studies conducted in both yeast and mammalian cells have demonstrated that this alteration produces a protein that cannot activate transcription, is defective in DNA binding, suppression of cell growth, and induction of apoptosis (Monti P et al., Mol. Cancer Res. 2011 Mar; 9(3):271-9. Malcikova Jet al., Biol. Chem. ; 391(2-3):197-205; Lomax M et al., Oncogene 1998 Aug; 17(5):643-9). Based on the available evidence, p.L344P is classified as a pathogenic mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.49
Cadd	Pathogenic	27
Dann	Uncertain	1.0
Eigen	Pathogenic	0.71
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.61	T;T;.;.;.;T;T;T
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	A;A;A;A;A;A
PrimateAI	Uncertain	0.57	T
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D;D
Polyphen		0.99	.;.;.;D;.;D;.;.
Vest4		0.91
MutPred		0.93		.;.;.;Loss of stability (P = 0.1061);.;Loss of stability (P = 0.1061);.;.;
MVP		0.99
MPC		0.47
ClinPred		0.99	D
GERP RS		5.4
Varity_R		0.98
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: rs121912662; hg19: chr17-7573996; COSMIC: COSV52687285; COSMIC: COSV52687285;