Our verdict is Likely pathogenic. Variant got 7 ACMG points: 8P and 1B. PM1PM2PM5PP3_ModerateBP6
The NM_000251.3(MSH2):c.1825G>T(p.Ala609Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,854 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A609G) has been classified as Uncertain significance.
MSH2 (HGNC:7325): (mutS homolog 2) This locus is frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). When cloned, it was discovered to be a human homolog of the E. coli mismatch repair gene mutS, consistent with the characteristic alterations in microsatellite sequences (RER+ phenotype) found in HNPCC. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]
Verdict is Likely_pathogenic. Variant got 7 ACMG points.
PM1
?
PM1 - Located in a mutational hot spot and/or critical and well-established functional domain (e.g., active site of an enzyme) without benign variation
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 13 benign, 13 uncertain in NM_000251.3
PM2
?
PM2 - Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium
Very rare variant in population databases, with high coverage;
PM5
?
PM5 - Novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen before
Other missense variant is known to change same aminoacid residue: Variant chr2-47475091-C-T is described in Lovd as [Pathogenic].
PP3
?
PP3 - Multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.)
MetaRNN computational evidence supports a deleterious effect, 0.884
BP6
?
BP6 - Reputable source recently reports variant as benign, but the evidence is not available to the laboratory to perform an independent evaluation
Variant 2-47475090-G-T is Benign according to our data. Variant chr2-47475090-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 230023.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=5, Likely_benign=2}.
Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Feb 22, 2023
This missense variant replaces alanine with serine at codon 609 of the MSH2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 2/251474 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Likely benign, criteria provided, single submitter
clinical testing
Ambry Genetics
Dec 08, 2021
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. -
MSH2-related disorder Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
PreventionGenetics, part of Exact Sciences
Nov 16, 2022
The MSH2 c.1825G>T variant is predicted to result in the amino acid substitution p.Ala609Ser. This variant has been reported in an individual with cancer (Table S5, Li et al. 2020. PubMed ID: 31391288). This variant is reported in 0.012% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/2-47702229-G-T), and is interpreted as uncertain significance in ClinVar (https://preview.ncbi.nlm.nih.gov/clinvar/variation/230023/). A different substitution affecting the same amino acid (p.Ala609Val) has been reported in patients with Extramammary Paget disease (Kang et al. 2016. PubMed ID: 27487738; Supplemetary eTable2, Jiang et al. 2019. PubMed ID: 30521064). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Apr 03, 2023
This missense variant replaces alanine with serine at codon 609 of the MSH2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 2/251474 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Oct 18, 2019
Not observed at a significant frequency in large population cohorts (Lek 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Observed in individuals with cancer (Li 2019); This variant is associated with the following publications: (PMID: 31391288, 22712459) -