rs1554898159

Positions:

• chr10-87933172-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001304718.2(PTEN):​c.-338A>G variant causes a 5 prime UTR premature start codon gain 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 (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PTEN NM_001304718.2 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 8.88

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]

PTEN (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.958

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTEN	NM_000314.8	c.413A>G	p.Tyr138Cys	missense_variant	5/9	ENST00000371953.8	NP_000305.3
PTEN	NM_001304718.2	c.-338A>G		5_prime_UTR_premature_start_codon_gain_variant	4/9		NP_001291647.1
PTEN	NM_001304717.5	c.932A>G	p.Tyr311Cys	missense_variant	6/10		NP_001291646.4
PTEN	NM_001304718.2	c.-338A>G		5_prime_UTR_variant	4/9		NP_001291647.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTEN	ENST00000371953.8	c.413A>G	p.Tyr138Cys	missense_variant	5/9	1	NM_000314.8	ENSP00000361021.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

PTEN hamartoma tumor syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 22, 2021	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 variant affects PTEN protein function (PMID: 22375056, 23085752, 26450531). 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: "Probably Damaging"; Align-GVGD: "Not Available"). ClinVar contains an entry for this variant (Variation ID: 486230). This variant has not been reported in the literature in individuals affected with PTEN-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces tyrosine with cysteine at codon 138 of the PTEN protein (p.Tyr138Cys). The tyrosine residue is highly conserved and there is a large physicochemical difference between tyrosine and cysteine. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Aug 15, 2023	This missense variant replaces tyrosine with cysteine at codon 138 of the PTEN protein. Computational prediction tool suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >=0.7, PMID: 27666373). Functional studies have shown that this mutant protein retains lipid phosphotase activity, but lacks protein phosphotase activity (PMID: 22375056). To our knowledge, this variant has not been reported in individuals affected with PTEN-related disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 16, 2023

The p.Y138C variant (also known as c.413A>G), located in coding exon 5 of the PTEN gene, results from an A to G substitution at nucleotide position 413. The tyrosine at codon 138 is replaced by cysteine, an amino acid with highly dissimilar properties. This alteration, identified in a lung cancer cell line, has been shown to lack lack protein phosphatase activity, but retain lipid phosphatase activity (Tibarewal P et al. Sci Signal, 2012 Feb;5:ra18; Kusunose M et al. Cancer Sci., 2015 Dec;106:1693-704; Berglund FM et al. Oncogene, 2013 Sep;32:4417-26). This amino acid position is highly 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D
M_CAP	Pathogenic	0.69	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.8	M
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-8.3	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.053	T
Polyphen		1.0	D
Vest4		0.93
MutPred		0.75		Gain of catalytic residue at L139 (P = 0.0193);
MVP		0.98
MPC		2.5
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.98
gMVP		0.99

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: rs1554898159; hg19: chr10-89692929; COSMIC: COSV64306562;