rs121909234

Positions:

• chr10-87957867-G-A
• chr10-87957867-G-C
• chr10-87957867-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 5P and 1B. PM1 PM2 PP2 BP4

The NM_000314.8(PTEN):​c.649G>A​(p.Val217Ile) 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 benign outcome for this variant. 13/21 in silico tools predict a benign 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. V217G) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PTEN NM_000314.8 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts P:1 U:2
• Conservation: PhyloP100: 9.53

Genes affected

PTEN (HGNC:9588): (phosphatase and tensin homolog) This gene was identified as a tumor suppressor that is mutated in a large number of cancers at high frequency. The protein encoded by this gene is a phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase. It contains a tensin like domain as well as a catalytic domain similar to that of the dual specificity protein tyrosine phosphatases. Unlike most of the protein tyrosine phosphatases, this protein preferentially dephosphorylates phosphoinositide substrates. It negatively regulates intracellular levels of phosphatidylinositol-3,4,5-trisphosphate in cells and functions as a tumor suppressor by negatively regulating AKT/PKB signaling pathway. The use of a non-canonical (CUG) upstream initiation site produces a longer isoform that initiates translation with a leucine, and is thought to be preferentially associated with the mitochondrial inner membrane. This longer isoform may help regulate energy metabolism in the mitochondria. A pseudogene of this gene is found on chromosome 9. Alternative splicing and the use of multiple translation start codons results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Feb 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 uncertain in NM_000314.8
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PTEN. . Gene score misZ 3.4883 (greater than the threshold 3.09). Trascript score misZ 4.1129 (greater than threshold 3.09). GenCC has associacion of gene with Lhermitte-Duclos disease, Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, macrocephaly-autism syndrome, Cowden syndrome 1, Cowden disease, Proteus-like syndrome, leiomyosarcoma, activated PI3K-delta syndrome, PTEN hamartoma tumor syndrome, glioma susceptibility 2, renal cell carcinoma.
• BP4: Computational evidence support a benign effect (MetaRNN=0.40367016).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PTEN	NM_000314.8	c.649G>A	p.Val217Ile	missense_variant	7/9	ENST00000371953.8
PTEN	NM_001304717.5	c.1168G>A	p.Val390Ile	missense_variant	8/10
PTEN	NM_001304718.2	c.58G>A	p.Val20Ile	missense_variant	7/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PTEN	ENST00000371953.8	c.649G>A	p.Val217Ile	missense_variant	7/9	1	NM_000314.8	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Melanoma Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Sep 01, 2000

- -

PTEN hamartoma tumor syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 09, 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 does not substantially affect PTEN function (PMID: 29706350). 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: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available"). ClinVar contains an entry for this variant (Variation ID: 7838). This variant has not been reported in the literature in individuals affected with PTEN-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 isoleucine, which is neutral and non-polar, at codon 217 of the PTEN protein (p.Val217Ile). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 26, 2023

The p.V217I variant (also known as c.649G>A), located in coding exon 7 of the PTEN gene, results from a G to A substitution at nucleotide position 649. The valine at codon 217 is replaced by isoleucine, an amino acid with highly similar properties. In a massively parallel functional assay using a humanized yeast model, lipid phosphatase activity for this variant was functionally neutral (Mighell TL et al. Am J Hum Genet, 2018 May;102:943-955). This variant demonstrated wild type-like intracellular protein abundance in a massively parallel functional assay (Matreyek KA et al. Nat Genet, 2018 Jun;50:874-882). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Uncertain	0.031	T
BayesDel_noAF	Benign	-0.19
CADD	Benign	23
DANN	Benign	0.95
DEOGEN2	Uncertain	0.49	T;.
Eigen	Benign	0.016
Eigen_PC	Benign	0.22
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D
M_CAP	Benign	0.057	D
MetaRNN	Benign	0.40	T;T
MetaSVM	Benign	-0.54	T
MutationAssessor	Benign	1.0	L;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-0.080	N;.
REVEL	Benign	0.27
Sift	Benign	0.66	T;.
Sift4G	Benign	0.85	T;T
Polyphen		0.12	B;.
Vest4		0.69
MutPred		0.49		Gain of sheet (P = 0.0344);.;
MVP		0.77
MPC		1.1
ClinPred		0.94	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7
Varity_R		0.12
gMVP		0.79

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: rs121909234; hg19: chr10-89717624; COSMIC: COSV64310398;