Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PP3_Strong
The NM_000535.7(PMS2):c.2527T>C(p.Cys843Arg) variant causes a missense change involving the alteration of a conserved nucleotide. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar 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]
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This variant has not been reported in the published literature. It also has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -
Review Status: criteria provided, single submitter
Collection Method: clinical testing
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. 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 expected to disrupt PMS2 protein function. ClinVar contains an entry for this variant (Variation ID: 525679). This variant has not been reported in the literature in individuals affected with PMS2-related conditions. The frequency data for this variant in the population databases (gnomAD) is considered unreliable due to the presence of homologous sequence, such as pseudogenes or paralogs, in the genome. This sequence change replaces cysteine, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 843 of the PMS2 protein (p.Cys843Arg). -
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The p.C843R variant (also known as c.2527T>C), located in coding exon 15 of the PMS2 gene, results from a T to C substitution at nucleotide position 2527. The cysteine at codon 843 is replaced by arginine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -