Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate
The ENST00000265849.12(PMS2):c.595C>T(p.Arg199Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000304 in 1,613,616 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R199H) has been classified as Uncertain significance.
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]
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Oct 20, 2022
The p.R199C variant (also known as c.595C>T), located in coding exon 6 of the PMS2 gene, results from a C to T substitution at nucleotide position 595. The arginine at codon 199 is replaced by cysteine, an amino acid with highly dissimilar properties. This alteration has been detected in 1/1260 individuals with a history of Lynch syndrome-associated cancer and/or polyps (Yurgelun MB et al. Gastroenterology. 2015 Sep;149:604-13.e20). 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. -
Uncertain significance, no assertion criteria provided
clinical testing
True Health Diagnostics
Jul 31, 2018
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Uncertain significance, criteria provided, single submitter
curation
Sema4, Sema4
Dec 29, 2021
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Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Nov 10, 2022
This missense variant replaces arginine with cysteine at codon 199 of the PMS2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with Lynch syndrome-associated cancer and/or polyps (PMID: 25980754) and in individuals affected with breast cancer (PMID: 25186627, 33471991). This variant has been identified in 9/282888 chromosomes 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 provided Uncertain:3
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Aug 19, 2024
In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Observed in individuals with breast cancer or a Lynch syndrome-associated cancer and/or polyps (PMID: 33471991, 25186627, 25980754); This variant is associated with the following publications: (PMID: 29570743, 25980754, 25589618, 25186627, 29887214, 33471991, 11574484, 36243179) -
Uncertain significance, criteria provided, single submitter
clinical testing
CeGaT Center for Human Genetics Tuebingen
Mar 01, 2017
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Uncertain significance, criteria provided, single submitter
clinical testing
Quest Diagnostics Nichols Institute San Juan Capistrano
Sep 08, 2023
In the published literature, this variant has been reported in individuals with breast cancer (PMIDs: 25186627 (2015), 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/genes/PMS2)), and suspected Lynch syndrome (PMID: 25980754 (2015)). This variant was also observed in healthy control individuals (PMID: 36243179 (2022)). The frequency of this variant in the general population, 0.00016 (5/30616 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded conflicting predictions that this variant is benign or damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -
Lynch syndrome 4 Uncertain:3
Uncertain significance, criteria provided, single submitter
clinical testing
Counsyl
Mar 02, 2016
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Uncertain significance, criteria provided, single submitter
clinical testing
Myriad Genetics, Inc.
Apr 04, 2023
This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
Uncertain significance, criteria provided, single submitter
clinical testing
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Sep 01, 2022
The PMS2 c.595C>T (p.Arg199Cys) missense change has a maximum subpopulation frequency of 0.016% in gnomAD v2.1.1 including 1 homozygote (https://gnomad.broadinstitute.org/). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant has been reported in at least one individual with Lynch syndrome-associated cancer and/or polyps (PMID: 25980754). In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
Lynch syndrome Uncertain:2
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Sep 23, 2024
This missense variant replaces arginine with cysteine at codon 199 of the PMS2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with Lynch syndrome-associated cancer and/or polyps (PMID: 25980754) and in individuals affected with breast cancer (PMID: 25186627, 33471991). This variant has been identified in 9/282888 chromosomes 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. -
Uncertain significance, criteria provided, single submitter
clinical testing
University of Washington Department of Laboratory Medicine, University of Washington
May 01, 2018
PMS2 NM_000535.5:c.595C>T has a 14.1% probability of pathogenicity based on combining prior probability from public data with a likelihood ratio of 0.16 to 1, generated from evidence of seeing this as a somatic mutation in a tumor with loss of heterozygosity at the PMS2 locus. See Shirts et al 2018, PMID 29887214. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Apr 24, 2024
Variant summary: PMS2 c.595C>T (p.Arg199Cys) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 251492 control chromosomes, predominantly at a frequency of 0.00016 within the South Asian subpopulation in the gnomAD database, including 1 homozygotes. However, this data must be interpreted with caution as the sequencing techology utalized does not distinguish between this gene and highly homologous pseudogenes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.595C>T, has been reported in the literature in individuals affected with Lynch Syndrome (Tung_2015, Yurgelun_2015). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Nonpolyposis Colorectal Cancer. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 25980754, 25186627). ClinVar contains an entry for this variant (Variation ID: 187514). Based on the evidence outlined above, the variant was classified as uncertain significance. -
PMS2-related disorder Uncertain:1
Uncertain significance, no assertion criteria provided
clinical testing
PreventionGenetics, part of Exact Sciences
Dec 06, 2023
The PMS2 c.595C>T variant is predicted to result in the amino acid substitution p.Arg199Cys. This variant has been reported in a cohort of individuals with suspected Lynch syndrome (Yurgelun et al. 2015. PubMed ID: 25980754, supplemental table 2), and individuals with breast cancer (Tung et al. 2015. PubMed ID: 25186627, supplemental table; reported as chr7_6038849_G_A in supplementary tables, Breast Cancer Association et al. 2021. PubMed ID: 33471991). However, its pathogenicity was not determined with further studies (e.g. segregation, functional assays). This variant has a subpopulation frequency of up to 0.016% in the gnomAD database, including one homozygote and it is reported as likely benign and uncertain in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/187514/). Although we suspect that this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -