# NM_000535.7(PMS2):c.1634_1635del (p.Ser545fs)

https://sugi.bio/variant/pms2-p-ser545fs

## Summary

**PMS2 p.Ser545fs (c.1634_1635del)** is classified **Pathogenic/Likely pathogenic** in PMS2 (ClinVar, Multiple submitters, 4 submitters; last evaluated 2025-10-31). No allele count reported in gnomAD v4.1 (AN 1,614,026); Associated with hereditary neoplastic syndrome.

**At a glance:** Pathogenic/Likely pathogenic · review: Multiple submitters · rsID rs753256070 · 4 submitters · 3 linked conditions · no allele count reported in gnomAD v4.1 (AN 1,614,026)

## For patients & families {#patients}

This is a change in the PMS2 gene that is considered likely disease-causing, submitted by 4 submitters, and is linked to hereditary neoplastic syndrome.

*Reference information, not medical advice, and not a prediction for any individual. A genetic counselor or clinician can interpret what it means for you and your family.*

|  |  |
| --- | --- |
| Clinical trials | 31 registered for this condition — see ClinicalTrials.gov |

**Support & next steps:** [Condition overview & support (NIH GARD)](https://rarediseases.info.nih.gov/diseases/0019921/index) · [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [PMS2](https://sugi.bio/atlas/gene/PMS2/) |
| Protein change (HGVS p.) | p.Ser545fs |
| Coding change (HGVS c.) | c.1634_1635del |
| MANE Select transcript | [NM_000535](https://www.ncbi.nlm.nih.gov/nuccore/NM_000535) |
| dbSNP | [rs753256070](https://www.ncbi.nlm.nih.gov/snp/rs753256070/) |
| Variant type | Microsatellite |
| Location | chr7:5987130-5987131 (GRCh38) |
| ClinVar | [VCV496032](https://www.ncbi.nlm.nih.gov/clinvar/variation/496032/) |

**All HGVS expressions:** `LRG_161:g.26974CT[1]`, `LRG_161t1:c.1634_1635del`, `NC_000007.13:g.6026761AG[1]`, `NC_000007.14:g.5987130AG[1]`, `NG_008466.1:g.26974CT[1]`, `NM_000535.7:c.1634_1635del`, `NM_001322003.2:c.1229_1230del`, `NM_001322004.2:c.1229_1230del`, `NM_001322005.2:c.1229_1230del`, `NM_001322006.2:c.1478_1479del`, `NM_001322007.2:c.1316_1317del`, `NM_001322008.2:c.1316_1317del`, `NM_001322009.2:c.1229_1230del`, `NM_001322010.2:c.1073_1074del`, `NM_001322011.2:c.701_702del`, `NM_001322012.2:c.701_702del`, `NM_001322013.2:c.1061_1062del`, `NM_001322014.2:c.1634_1635del`, `NM_001322015.2:c.1325_1326del`, `NR_136154.1:n.1719CT[1]`

## Computational & population evidence {#evidence}

**Concordance:** Mixed / partial computational evidence (see below).

- **Missense predictors (AlphaMissense/REVEL/SaProt) do not apply** to this variant type — they score amino-acid substitutions only. For non-missense variants the computational signal comes from conservation (below), not from a missing predictor score.
- Conservation: phyloP -0.004 — not a conserved position (phyloP < 0.1, ACGS BP7 cut)
- Molecular consequence: **frameshift** — a predicted loss-of-function variant. ClinGen curates **sufficient evidence for haploinsufficiency** in this gene, supporting a loss-of-function disease mechanism. *Descriptive; not an applied PVS1 code.*
- Nonsense-mediated decay: the premature termination codon is **in exon 11 of 15**, so the transcript is predicted to undergo NMD.
- SpliceAI: **not assessed** — the release is built from a substitutions-only source, so it holds no microsatellite variants. That is a property of the dataset, not of the variant, and is not evidence against a splicing effect.
- Repeat context: **segmental_duplication** (chr7:6735644). Short reads may not map uniquely here, so both the call and its population frequency are less reliable. *A qualifier on how reliably this variant can be called and counted — not a pathogenicity signal.*
- Population frequency: **no allele count reported in gnomAD v4.1 (AN 1,614,026)** — rarity (ACMG PM2) and BA1/BS1 cannot be assessed for this variant.

*Computational predictors are not independent (ClinGen Variant Classification guidance): AlphaMissense (Cheng et al. 2023) carries the ACMG weight for missense and conservation (phyloP/GERP/phastCons) for non-missense; REVEL (Pejaver-2022 calibrated strength bands) and SaProt (Su et al. 2023, structure-aware, ClinVar-independent protein language model, raw LLR) are shown as orthogonal agreement signals, not additive. For frequency, the gnomAD v4.1 grpmax filtering allele frequency (FAF95) is ClinGen's designated BA1/BS1 input (gnomAD v4 guidance v3.0, June 2025); BA1/BS1 thresholds are disease-specific, not a blanket 5%. Predictions, not a clinical determination.*

## Gene constraint & dosage {#gene-context}

**PMS2** population constraint: LOEUF 0.898, pLI 5.3905e-09, missense-Z 0.36886; ClinGen dosage — haploinsufficiency 3/3, triplosensitivity 0/3. *Lower LOEUF and higher pLI indicate a gene that tolerates loss-of-function poorly; ClinGen dosage is the curated haploinsufficiency call.*

Curated gene–disease validity (ClinGen):

- **Lynch syndrome** — Definitive (AD)
- **hereditary breast carcinoma** — Disputed (AD)
- **mismatch repair cancer syndrome 1** — Definitive (AR)

## Protein context {#protein}

Residue **545** lies in the 'disordered' region.

AlphaFold model confidence (whole protein): pLDDT 71.37, 36% of residues very-high.

**9 experimental structure(s)** (PDB): [1EA6](https://www.rcsb.org/structure/1EA6), [1H7S](https://www.rcsb.org/structure/1H7S), [1H7U](https://www.rcsb.org/structure/1H7U), [5U5R](https://www.rcsb.org/structure/5U5R), [6MFQ](https://www.rcsb.org/structure/6MFQ), [7RCB](https://www.rcsb.org/structure/7RCB) — incl. mutant structure 6MFQ.

## What this gene does {#gene-function}

*Describes the biological roles of PMS2 (the gene this variant disrupts) — not effects measured for this specific variant. A damaging variant is expected to affect these functions and pathways; the degree depends on the variant.*

**How this variant is thought to act:** PMS2's established molecular role includes DNA binding. p.Ser545fs falls in the disordered region. In Reactome, PMS2 is annotated in disease pathway(s) including **Defective Mismatch Repair Associated With MLH1**, **Defective Mismatch Repair Associated With PMS2**.

**Disease mechanism (Reactome):** PMS2 loss or alteration is curated in [Defective Mismatch Repair Associated With MLH1](https://reactome.org/content/detail/R-HSA-5545483), [Defective Mismatch Repair Associated With PMS2](https://reactome.org/content/detail/R-HSA-5632987).

### Pathways affected {#pathways}

PMS2 participates in **6 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| ⚕ [Defective Mismatch Repair Associated With MLH1](https://reactome.org/content/detail/R-HSA-5545483) | curated |
| ⚕ [Defective Mismatch Repair Associated With PMS2](https://reactome.org/content/detail/R-HSA-5632987) | curated |
| [Mismatch repair (MMR) directed by MSH2:MSH6 (MutSalpha)](https://reactome.org/content/detail/R-HSA-5358565) | curated |
| [Somatic hypermutation of immunoglobulin genes by error-prone mismatch repair (MMR)](https://reactome.org/content/detail/R-HSA-9968295) | curated |
| [TP53 Regulates Transcription of DNA Repair Genes](https://reactome.org/content/detail/R-HSA-6796648) | curated |
| [Mismatch repair (MMR) directed by MSH2:MSH3 (MutSbeta)](https://reactome.org/content/detail/R-HSA-5358606) | electronic |

### Molecular function & processes (GO — experimentally supported) {#go}

**Molecular function:** DNA binding, single base insertion or deletion binding.

**Biological process:** meiotic mismatch repair, mismatch repair.

## Clinical significance {#significance}

**Pathogenic/Likely pathogenic** — review status Multiple submitters *(criteria provided, multiple submitters, no conflicts)*, last evaluated 2025-10-31.

**Submitter consensus:** conflicting (3 Pathogenic, 1 Likely pathogenic).

**Submission history:** 4 submissions (2017–2025); classifications have differed over time.

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Likely pathogenic | criteria provided, single submitter | clinical testing | 2017-08-21 |
| Myriad Genetics, Inc. | Pathogenic | criteria provided, single submitter | clinical testing | 2025-09-17 |
| Ambry Genetics | Pathogenic | criteria provided, single submitter | clinical testing | 2025-10-31 |
| Labcorp Genetics (formerly Invitae), Labcorp | Pathogenic | criteria provided, single submitter | clinical testing | 2024-05-26 |

## Associated conditions {#conditions}

[hereditary neoplastic syndrome](https://sugi.bio/atlas/disease/hereditary-neoplastic-syndrome/), [Lynch syndrome](https://sugi.bio/atlas/disease/lynch-syndrome/), [Lynch syndrome 4](https://sugi.bio/atlas/disease/lynch-syndrome-4/).

**Reported phenotype names (ClinVar):** Hereditary cancer-predisposing syndrome, Lynch syndrome, Hereditary nonpolyposis colorectal neoplasms, Lynch syndrome 4, Tumor predisposition, Neoplastic Syndromes, Hereditary, Hereditary neoplastic syndrome, Hereditary Cancer Syndrome, Colorectal cancer, hereditary nonpolyposis, type 4, Hereditary non-polyposis colorectal cancer, type 4.

## Similar variants {#similar}

Related PMS2 variant pages (same residue, condition, or type): [PMS2 p.Ser545Cys](/variant/pms2-p-ser545cys), [PMS2 p.Ser545Phe](/variant/pms2-p-ser545phe), [PMS2 p.Ser545Pro](/variant/pms2-p-ser545pro), [PMS2 p.Ser545Tyr](/variant/pms2-p-ser545tyr), [PMS2 p.Ser545=](/variant/pms2-p-ser545), [PMS2 p.Gly74fs](/variant/pms2-p-gly74fs), [PMS2 p.Lys748fs](/variant/pms2-p-lys748fs), [PMS2 p.Ala116fs](/variant/pms2-p-ala116fs).

### Data sources & attribution {#sources}

ClinVar (NCBI — public domain, built 2026-10-14); gnomAD v4.1 (Broad Institute, built 2026-10-06); AlphaMissense (Cheng et al. 2023, © Google DeepMind — CC BY 4.0, built 2026-01-27); REVEL (Ioannidis et al. 2016 — ODbL, built 2026-07-13); SaProt (Su et al. 2023 — MIT, built 2026-10-14); SpliceAI (Illumina — free for non-commercial use, built 2026-10-13); CADD (Rentzsch et al. 2019, University of Washington — free for non-commercial use, built 2026-10-10); Conservation (phyloP/phastCons/GERP) (UCSC hg38 470-way mammal (Hiller Lab) + Ensembl Compara, built 2026-07-12); gnomAD Non-coding Constraint (Gnocchi) (Chen et al. 2024, Broad Institute — CC0, built 2026-10-11); gnomAD Regional Missense Constraint (Broad Institute — CC0, built 2026-10-13); Pangolin (Zeng & Li 2022 — CC BY 4.0, built 2026-10-11); Repeat regions (UCSC — RepeatMasker, TRF, segmental duplications, built 2026-10-11); ClinGen (ClinGen, built 2026-09-22); UniProt (CC BY 4.0); Reactome / GO (CC BY 4.0, built 2026-09-23); MaveDB (per-record license, built 2026-10-11); CIViC (CC0, built 2026-09-22); Orphanet (Orphanet, built 2026-06-12)

*Primary record: NCBI ClinVar (variation 496032). Classifications reflect these databases as of the page's build date and may change. Free reference use — not medical advice; consult the primary submitters and a clinician.*