Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_StrongBP6BP7
The NM_000535.7(PMS2):c.354C>T(p.Ser118=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000023 in 1,609,730 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
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]
Verdict is Likely_benign. Variant got -6 ACMG points.
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.6).
BP6
Variant 7-6002636-G-A is Benign according to our data. Variant chr7-6002636-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 186067.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Uncertain_significance=2}. Variant chr7-6002636-G-A is described in Lovd as [Likely_benign].
BP7
Synonymous conserved (PhyloP=0.105 with no splicing effect.
Likely benign, criteria provided, single submitter
clinical testing
GeneDx
Apr 25, 2019
- -
Likely benign, no assertion criteria provided
clinical testing
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
-
- -
Likely benign, no assertion criteria provided
clinical testing
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
-
- -
Hereditary cancer-predisposing syndrome Benign:2
Likely benign, criteria provided, single submitter
clinical testing
Ambry Genetics
Sep 24, 2014
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Likely benign, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Sep 20, 2016
- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Nov 03, 2023
Variant summary: PMS2 c.354C>T (p.Ser118Ser) alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 9.2e-06 in 326304 control chromosomes (gnomAD; Okawa_2023). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.354C>T has been reported in the literature in individuals affected with breast cancer without strong evidence of causality (Hu_2022). This report does not provide unequivocal conclusions about association of the variant with Hereditary Nonpolyposis Colorectal Cancer. Co-occurrence with another pathogenic variant was reported in one of these individuals (MSH2 c.2633_2634del, p.Glu878fs), providing supporting evidence for a benign role. 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: 35449176, 36243179). Four submitters have cited clinical-significance assessments for this variant to ClinVar after 2014, and classified it as likely benign (n=3) or uncertain significance (n=1). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Breast and/or ovarian cancer Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
May 26, 2022
- -
Lynch syndrome Benign:1
Likely benign, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health