LYFE Sciences · Project HERA
Variant Interpretation · Classification Report
Variant classification summary
NM_000314.8:c.956del
PTEN
· NP_000305.3:p.(Thr319IlefsTer2)
· NM_000314.8
GRCh37: chr10:89720804 AC>A
·
GRCh38: chr10:87961047 AC>A
Gene:
PTEN
Transcript:
NM_000314.8
Final call
Likely Pathogenic
PVS1 very strong
PM2 supporting
Variant details
Gene
PTEN
Transcript
NM_000314.8
Protein
NP_000305.3:p.(Thr319IlefsTer2)
gnomAD AF
ClinVar
Pathogenic
OncoKB
Likely Oncogenic
Classification rationale
Interpretation summary
Generated evidence synthesis
1
The PTEN c.956del (p.Thr319IlefsTer2; p.T319Ifs*2) variant has been reported in ClinVar as Pathogenic by one clinical laboratory.
2
This variant is absent from gnomAD v2.1 and gnomAD v4.1, supporting rarity in population databases and meeting the PTEN PM2_Supporting threshold of less than 0.00001 (0.001%).
3
This frameshift is predicted to truncate PTEN at codon 320 in exon 8, and the PTEN-specific PVS1 decision tree assigns PVS1 to truncating variants at or 5' to p.D375 (c.1121) in transcript NM_000314.8.
4
SpliceAI predicts no significant splice effect for this variant (max delta score 0.02), and REVEL and BayesDel are not applicable because this is not a single-nucleotide missense variant.
Final determination:
Rule20 in the Richards et.al., 2015 - Combining rules v3.2.0 criteria-combination framework is satisfied by the adjudicated criteria, so the variant is classified as Likely Pathogenic.
Criteria assessment
ACMG/AMP criteria review
Criteria shown when status is available
All criteria require review: For research and educational purposes only.
| Criterion | Status | Rationale | Evidence used |
|---|---|---|---|
| PVS1 | Met | This variant is a frameshift, NM_000314.8:c.956del, predicted to cause p.(Thr319IlefsTer2) [p.(T319Ifs*2)] and truncate PTEN in exon 8 before the PTEN-specific p.D375 (c.1121) threshold. Under the PTEN-specific PVS1 decision tree, truncating variants at or 5' to this threshold in the biologically relevant transcript are assigned PVS1. |
cspec
pvs1_gene_context
pvs1_variant_assessment
vcep_pvs1_decisiontree_pten
|
| PS1 | N/A | PS1 applies to the same amino acid change as a previously established pathogenic variant. This variant is a frameshift, not a missense or equivalent same-amino-acid substitution. |
cspec
|
| PS2 | Not assessed | No confirmed de novo observation with maternity and paternity established was identified for this variant. |
clinvar
cspec
|
| PS3 | Not assessed | No PTEN functional study meeting the PTEN Expert Panel PS3 rules was identified for this variant. The available PTEN saturation mutagenesis resource is intended for missense phosphatase activity assessment, and no RNA assay showing an abnormal splicing effect was identified. |
cspec
vcep_mmc2
spliceai
|
| PS4 | Not assessed | This variant has a single ClinVar pathogenic submission, but no counted series of unrelated affected individuals, specificity score, or case-control enrichment data were identified to meet the PTEN PS4 rule. |
clinvar
cspec
|
| PM1 | N/A | PM1 in the PTEN specification is used for variants in defined catalytic motifs and hotspot functional regions. This variant is a frameshift at codon 319 and does not fit the PTEN PM1 missense-domain rule. |
cspec
hotspots
|
| PM2 | Met | This variant is absent from gnomAD v2.1 and gnomAD v4.1, which is below the PTEN PM2 threshold of less than 0.00001 (0.001%) allele frequency and consistent with rarity in population databases. |
cspec
gnomad_v2
gnomad_v4
|
| PM3 | N/A | PM3 is not applicable in the PTEN Expert Panel specification. |
cspec
|
| PM4 | N/A | PM4 in the PTEN specification applies to in-frame insertions or deletions affecting specified motifs or to stop-loss variants. This variant is a frameshift with a premature termination codon, so PM4 does not apply. |
cspec
|
| PM5 | N/A | PM5 in the PTEN specification uses classic same-residue missense logic. This variant is a frameshift, and the PM5 candidate review determined that classic missense PM5 is not applicable. |
cspec
pm5_candidates
|
| PM6 | Not assessed | No presumed de novo occurrence without full parental confirmation was identified for this variant. |
clinvar
cspec
|
| PP1 | Not assessed | No segregation data were identified showing this variant tracking with PTEN-related disease in informative relatives. |
cspec
clinvar
|
| PP2 | N/A | PP2 applies to missense variation. This variant is a frameshift. |
cspec
|
| PP3 | N/A | PP3 in the PTEN specification is used for splicing variants with concordant splice predictors or missense variants with REVEL greater than 0.7. This variant is a frameshift, REVEL and BayesDel were not applicable, and SpliceAI showed no significant splice effect with a max delta score of 0.02. |
cspec
spliceai
|
| PP4 | N/A | PP4 is not applicable in the PTEN Expert Panel specification because phenotype specificity is incorporated into PS4. |
cspec
|
| PP5 | N/A | PP5 is not applicable in the PTEN Expert Panel specification. |
cspec
|
| BA1 | Not met | This variant is absent from gnomAD v2.1 and gnomAD v4.1 and is therefore below the PTEN BA1 threshold of greater than 0.00056 (0.056%). |
cspec
gnomad_v2
gnomad_v4
|
| BS1 | Not met | This variant is absent from gnomAD v2.1 and gnomAD v4.1 and is therefore below the PTEN BS1 thresholds of 0.0000043 to 0.00056. |
cspec
gnomad_v2
gnomad_v4
|
| BS2 | Not assessed | No observation of this variant in a healthy or PTEN hamartoma tumor syndrome-unaffected homozygous individual was identified. |
cspec
gnomad_v2
gnomad_v4
|
| BS3 | Not assessed | No well-established PTEN functional study showing no damaging effect was identified for this variant. The available PTEN saturation mutagenesis resource is intended for missense variants and does not provide benign functional evidence for this frameshift. |
cspec
vcep_mmc2
|
| BS4 | Not assessed | No lack-of-segregation data were identified for this variant in one or more families. |
cspec
clinvar
|
| BP1 | N/A | BP1 is not applicable in the PTEN Expert Panel specification. |
cspec
|
| BP2 | Not assessed | No data were identified showing this variant in trans with a pathogenic PTEN variant or in cis/phase unknown with qualifying pathogenic PTEN variants. |
cspec
|
| BP3 | N/A | BP3 is not applicable in the PTEN Expert Panel specification. |
cspec
|
| BP4 | N/A | BP4 in the PTEN specification is used for synonymous or intronic variants with benign splice predictions or missense variants with REVEL less than 0.5. This variant is a frameshift, and although SpliceAI predicts no significant splice impact with a max delta score of 0.02, that does not make BP4 applicable to a truncating coding deletion. |
cspec
spliceai
|
| BP5 | Not assessed | No alternate molecular diagnosis was identified that would explain the phenotype without overlap with PTEN-related disease. |
cspec
|
| BP6 | N/A | BP6 is not applicable in the PTEN Expert Panel specification. |
cspec
|
| BP7 | N/A | BP7 applies to synonymous or qualifying intronic variants with no predicted splice impact. This variant is a coding frameshift deletion, so BP7 does not apply. |
cspec
spliceai
|
Disclaimer:
The content and results provided by LYFE Sciences are for research and educational purposes only and must not be used as a substitute for professional medical judgment, diagnosis, or treatment. Always consult a qualified healthcare professional before making any clinical decisions.