Our verdict is Likely benign. Variant got -1 ACMG points: 0P and 1B. BP4
The ENST00000265849.12(PMS2):c.1253C>T(p.Ser418Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000929 in 1,614,072 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 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. S418A) has been classified as Likely benign.
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
Quest Diagnostics Nichols Institute San Juan Capistrano
Sep 28, 2022
The frequency of this variant in the general population, 0.000008 (2/251182 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in an individual with lung adenocarcinoma (PMID: 26689913 (2015)). In a large-scale breast cancer association study, the variant was observed one healthy control (PMID: 33471991 (2021), see also LOVD ( http://databases.lovd.nl/shared/genes/PMS2)). 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. -
Uncertain significance, criteria provided, single submitter
not provided
Breakthrough Genomics, Breakthrough Genomics
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Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Apr 03, 2023
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26689913, 34445161, 35475445, 32957588) -
Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Dec 21, 2022
This missense variant replaces serine with phenylalanine at codon 418 of the PMS2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual affected with lung adenocarcinoma (PMID: 26689913) and one individual affected with breast cancer (PMID: 32957588). This variant has been identified in 2/251182 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
Ambry Genetics
Dec 07, 2023
The p.S418F variant (also known as c.1253C>T), located in coding exon 11 of the PMS2 gene, results from a C to T substitution at nucleotide position 1253. The serine at codon 418 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This alteration has been reported in a lung cancer patient from a cohort of 4034 cancer cases from The Cancer Genome Atlas (Lu C et al. Nat Commun. 2015 Dec 22;6:10086). This variant was also identified by multigene panel testing in an Italian individual who was diagnosed with invasive breast cancer at age 39; her family history did not meet Amsterdam criteria (Germani A et al. J Clin Med, 2020 Sep;9:). This alteration has also been reported in an individual, from a family meeting Amsterdam criteria, with colon cancer diagnosed at age 49 that was MSI-H and MLH1/PMS2 deficient on IHC, and the patient's brother who was also affected with colon cancer (Liccardo R et al. Int J Mol Med, 2022 Jun;49:). This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Genetic Services Laboratory, University of Chicago
Nov 11, 2016
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Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Sep 23, 2024
This missense variant replaces serine with phenylalanine at codon 418 of the PMS2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual affected with lung adenocarcinoma (PMID: 26689913) and one individual affected with breast cancer (PMID: 32957588). This variant has been identified in 2/251182 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
Labcorp Genetics (formerly Invitae), Labcorp
Jan 25, 2024
This sequence change replaces serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 418 of the PMS2 protein (p.Ser418Phe). This variant is present in population databases (rs587782640, gnomAD 0.002%). This missense change has been observed in individual(s) with colon or lung cancer (PMID: 26689913, 35475445). ClinVar contains an entry for this variant (Variation ID: 142680). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt PMS2 protein function with a negative predictive value of 80%. 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. -
Lynch syndrome 4 Uncertain:1
Uncertain significance, criteria provided, single submitter