Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1PS1_ModeratePM2PP5_Very_Strong
The NM_000535.7(PMS2):c.3G>T(p.Met1?) variant causes a start lost change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).
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]
AIMP2 (HGNC:20609): (aminoacyl tRNA synthetase complex interacting multifunctional protein 2) The protein encoded by this gene is part of the aminoacyl-tRNA synthetase complex, which contains nine different aminoacyl-tRNA synthetases and three non-enzymatic factors. The encoded protein is one of the non-enzymatic factors and is required for assembly and stability of the complex. [provided by RefSeq, May 2016]
Verdict is Pathogenic. Variant got 20 ACMG points.
PVS1
Start lost variant, next in-frame start position is after 13 pathogenic variants. Next in-frame start position is after 136 codons. Genomic position: 6002584. Lost 0.157 part of the original CDS.
PS1
Another start lost variant in NM_000535.7 (PMS2) was described as [Pathogenic] in Lovd
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 7-6009017-C-A is Pathogenic according to our data. Variant chr7-6009017-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 1429521.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This sequence change affects the initiator methionine of the PMS2 mRNA. The next in-frame methionine is located at codon 136. This variant is not present in population databases (gnomAD no frequency). Disruption of the initiator codon has been observed in individual(s) with clinical features of Lynch syndrome and/or constitutional mismatch repair deficiency syndrome (PMID: 18602922, 23709753, 25980754, 27476653). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 1429521). For these reasons, this variant has been classified as Pathogenic. -
Lynch syndrome 4 Pathogenic:1
Sep 15, 2023
Myriad Genetics, Inc.
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This variant is considered pathogenic. This variant is located within the gene translation start codon (p.Met1?) and is predicted to result in abnormal protein translation. This variant has been reported in multiple individuals with clinical features of gene-specific disease [PMID: 30680046, 27476653, 18602922]. -