Our verdict is Likely pathogenic. Variant got 9 ACMG points: 10P and 1B. PM1PM2PM5PP3_StrongBP6
The NM_000251.3(MSH2):c.2048G>A(p.Gly683Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging 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. G683R) has been classified as Pathogenic.
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 9 ACMG points.
PM1
In a helix (size 16) in uniprot entity MSH2_HUMAN there are 14 pathogenic changes around while only 0 benign (100%) in NM_000251.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-47476408-G-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.987
BP6
Variant 2-47476409-G-A is Benign according to our data. Variant chr2-47476409-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 489931.We mark this variant Likely_benign, oryginal submissions are: {Benign=1, Uncertain_significance=1}.