Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_000535.7(PMS2):c.121G>T(p.Glu41*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,552 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.
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 Pathogenic. Variant got 18 ACMG points.
PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 7-6005934-C-A is Pathogenic according to our data. Variant chr7-6005934-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 219674.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing
Variant summary: PMS2 c.121G>T (p.Glu41X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 4.1e-06 in 245778 control chromosomes. c.121G>T has been reported in the literature in at least one individual affected with colorectal and endometrial cancer (e.g. Mork_2019). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 31101557). ClinVar contains an entry for this variant (Variation ID: 219674). Based on the evidence outlined above, the variant was classified as pathogenic. -
Review Status: criteria provided, single submitter
Collection Method: clinical testing
ClinVar contains an entry for this variant (Variation ID: 219674). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant has not been reported in the literature in individuals affected with PMS2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change creates a premature translational stop signal (p.Glu41*) in the PMS2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PMS2 are known to be pathogenic (PMID: 21376568, 24362816). -
Lynch syndrome 4 Pathogenic:1
Sep 18, 2023
Myriad Genetics, Inc.
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This variant is considered pathogenic. This variant creates a termination codon and is predicted to result in premature protein truncation. -