7-5997349-GG-CC

Variant names:

• chr7-5997349-GG-CC
• rs730881920
• NM_000535.7:c.779_780delCCinsGG

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_000535.7(PMS2):​c.779_780delCCinsGG​(p.Ser260Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. 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. S260L) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 27)
• Consequence: PMS2 NM_000535.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 0.588
• Publications: 5 publications found

Genes affected

PMS2 (HGNC:9122): (PMS1 homolog 2, mismatch repair system component) The protein encoded by this gene is a key component of the mismatch repair system that functions to correct DNA mismatches and small insertions and deletions that can occur during DNA replication and homologous recombination. This protein forms heterodimers with the gene product of the mutL homolog 1 (MLH1) gene to form the MutL-alpha heterodimer. The MutL-alpha heterodimer possesses an endonucleolytic activity that is activated following recognition of mismatches and insertion/deletion loops by the MutS-alpha and MutS-beta heterodimers, and is necessary for removal of the mismatched DNA. There is a DQHA(X)2E(X)4E motif found at the C-terminus of the protein encoded by this gene that forms part of the active site of the nuclease. Mutations in this gene have been associated with hereditary nonpolyposis colorectal cancer (HNPCC; also known as Lynch syndrome) and Turcot syndrome. [provided by RefSeq, Apr 2016]

PMS2 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Lynch syndrome 4

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• mismatch repair cancer syndrome 4

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• ovarian cancer

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• Muir-Torre syndrome

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• breast cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• prostate cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PMS2	NM_000535.7	c.779_780delCCinsGG	p.Ser260Trp	missense_variant		ENST00000265849.12	NP_000526.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PMS2	ENST00000265849.12	c.779_780delCCinsGG	p.Ser260Trp	missense_variant		1	NM_000535.7	ENSP00000265849.7

Frequencies

GnomAD3 genomes Cov.: 27

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 27

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Feb 19, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.779_780delCCinsGG variant (also known as p.S260W), located in coding exon 7 of the PMS2 gene, results from a C to G substitution at nucleotide positions 779 and 780. The serine at codon 260 is replaced by tryptophan, an amino acid with highly dissimilar properties. This amino acid position is not well conserved in available vertebrate species. Based on the available evidence, the clinical significance of this variant remains unclear. -

Mar 10, 2025

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces serine with tryptophan at codon 260 of the PMS2 protein. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with PMS2-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. -

not specified Uncertain:1

Oct 10, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: PMS2 c.779_780delinsGG (p.Ser260Trp) results in a non-conservative amino acid change located in the DNA mismatch repair protein, S5 domain 2-like (IPR013507) of the encoded protein sequence. Three of three in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 281520 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.779_780delinsGG in individuals affected with Lynch Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Three submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Lynch syndrome Uncertain:1

Apr 02, 2024

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Dec 16, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with tryptophan, which is neutral and slightly polar, at codon 260 of the PMS2 protein (p.Ser260Trp). Information on the frequency of this variant in the gnomAD database is not available, as this variant may be reported differently in the database. This variant has not been reported in the literature in individuals affected with PMS2-related conditions. ClinVar contains an entry for this variant (Variation ID: 232473). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.59

Splicing

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

Other links and lift over

dbSNP: rs730881920; hg19: chr7-6036980;