Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3
The NM_000251.3(MSH2):c.210A>G(p.Ala70Ala) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar 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]
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The c.210A>G variant (also known as p.A70A), located in coding exon 1 of the MSH2 gene, results from an A to G substitution at nucleotide position 210. This nucleotide substitution does not change the amino acid at codon 70. This nucleotide position is well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will result in the creation or strengthening of a novel splice donor site. Based on the available evidence, the clinical significance of this variant remains unclear. -