Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_000535.7(PMS2):c.1500delC(p.Val501TrpfsTer94) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,144 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. S500S) has been classified as Likely benign. 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 7-5987264-CG-C is Pathogenic according to our data. Variant chr7-5987264-CG-C is described in ClinVar as [Pathogenic]. Clinvar id is 224541.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 creates a premature translational stop signal (p.Val501Trpfs*94) 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). This variant is present in population databases (rs759151952, gnomAD 0.009%). This premature translational stop signal has been observed in individual(s) with constitutional mismatch repair deficiency (CMMRD) and breast cancer (PMID: 26845104, 28381238). ClinVar contains an entry for this variant (Variation ID: 224541). For these reasons, this variant has been classified as Pathogenic. -
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The c.1500delC pathogenic mutation, located in coding exon 11 of the PMS2 gene, results from a deletion of one nucleotide at nucleotide position 1500, causing a translational frameshift with a predicted alternate stop codon (p.V501Wfs*94). This variant has been reported as a heterozygous variant in a Lynch syndrome family and a homozygous finding in an individual with constitutionl mismatch repair deficiency (CMMRD) (Shirts BH et al. Genet. Med., 2016 10;18:974-81; Ramchander NC et al. BMC Med. Genet., 2017 Apr;18:40). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -
Lynch syndrome 4 Pathogenic:1
Sep 20, 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 frameshift predicted to result in premature protein truncation. -