Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM1BP4_Moderate
The NM_000251.3(MSH2):c.1892G>A(p.Arg631Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign 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. R631S) 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 Uncertain_significance. Variant got 0 ACMG points.
PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 11 benign, 13 uncertain in NM_000251.3
BP4
Computational evidence support a benign effect (MetaRNN=0.19967818).
Likely benign, criteria provided, single submitter
clinical testing
Ambry Genetics
Jul 06, 2022
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. -
Uncertain significance, criteria provided, single submitter
curation
Sema4, Sema4
Aug 18, 2021
- -
Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Jun 12, 2019
- -
Lynch syndrome 1 Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Baylor Genetics
Jan 15, 2024
- -
Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Mar 28, 2023
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not provided Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
May 25, 2023
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Published functional studies suggest no impact on function: demonstrates sensitivity to 6-TG similar to wild type (Jia et al., 2020); Observed in an unaffected control in a case control study assessing melanoma and individuals with multiple cancers (Pritchard et al., 2018); This variant is associated with the following publications: (PMID: 18822302, 21120944, 29641532, 33357406) -
Uncertain significance, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
Oct 31, 2022
This sequence change replaces arginine, which is basic and polar, with lysine, which is basic and polar, at codon 631 of the MSH2 protein (p.Arg631Lys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MSH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 455532). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 33357406) indicates that this missense variant is not expected to disrupt MSH2 function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Muir-Torré syndrome;C2936783:Lynch syndrome 1;C5436806:Mismatch repair cancer syndrome 2 Uncertain:1
Uncertain significance, criteria provided, single submitter