10-87925558-G-T

Position:

• chr10-87925558-G-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000314.8(PTEN):​c.209+1G>T variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000707 in 1,414,988 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: PTEN NM_000314.8 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 9.29

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 Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.036303632 fraction of the gene. Cryptic splice site detected, with MaxEntScore 4.6, offset of 4, new splice context is: taaGTatgt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 10-87925558-G-T is Pathogenic according to our data. Variant chr10-87925558-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 229705.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTEN	NM_000314.8	c.209+1G>T		splice_donor_variant		ENST00000371953.8	NP_000305.3
PTEN	NM_001304717.5	c.728+1G>T		splice_donor_variant			NP_001291646.4
PTEN	NM_001304718.2	c.-540-5488G>T		intron_variant			NP_001291647.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTEN	ENST00000371953.8	c.209+1G>T		splice_donor_variant		1	NM_000314.8	ENSP00000361021	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.07e-7 AC: 1 AN: 1414988 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 705560

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: 0.0000212

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

PTEN hamartoma tumor syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 13, 2019

For these reasons, this variant has been classified as Pathogenic. Donor and acceptor splice site variants typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in PTEN are known to be pathogenic (PMID: 9467011, 21194675). This variant has been observed in several individuals affected with Cowden syndrome (PMID: 21194675, 24778394, 21659347, 20600018). ClinVar contains an entry for this variant (Variation ID: 229705). This variant is not present in population databases (ExAC no frequency). This sequence change affects a donor splice site in intron 3 of the PTEN gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 19, 2021

The c.209+1G>T intronic pathogenic mutation results from a G to T substitution one nucleotide after coding exon 3 of the PTEN gene. Alterations that disrupt the canonical splice site are expected to result in aberrant splicing. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). The resulting transcript is predicted to be in-frame and is not expected to trigger nonsense-mediated mRNAdecay. The exact functional effect of the altered amino acid sequence is unknown; however, the impacted region is critical for protein function (Ambry internal data). This variant has been identified in patients with clinical features of PTEN hamartoma syndrome (Tan MH, et al. Am. J. Hum. Genet. 2011 Jan; 88(1):42-56; Pilarski R et al. J Med Genet, 2011 Aug;48:505-12; Ambry internal data), breast cancer (Ngeow J, et al. J. Clin. Oncol. 2014 Jun; 32(17):1818-24) and colon polyps, including ganglioneuromas (Heald B et al. Gastroenterology, 2010 Dec;139:1927-33). Another alteration impacting the same donor site (c.209+1G>A) has been detected in cohorts of patients with features of Cowden syndrome and/or BRRS (Marsh DJ et al. Hum. Mol. Genet., 1999 Aug;8:1461-72; Pilarski R et al. J Med Genet, 2011 Aug;48:505-12; Tan MH et al. Am J Hum Genet. 2011 Jan;88(1):42-56), and functional analysis using patient mRNA has shown that this transcript has significantly reduced protein phosphatase activity despite being in-frame and stable due to exon 3 skipping (Agrawal S et al. Hum Mol Genet, 2005 Aug;14:2459-68). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D
GERP RS		5.5

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1554897280; hg19: chr10-89685315; COSMIC: COSV64291888;