Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1_ModeratePM2PP3_StrongPP5_Moderate
The NM_000251.3(MSH2):c.2459-1G>T variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely 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 Pathogenic. Variant got 10 ACMG points.
PVS1
?
PVS1 - null variant (nonsense, frameshift, canonical ±1 or 2 splice sites, initiation codon, single or multiexon deletion) in a gene where LOF is a known mechanism of disease
Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.06238859 fraction of the gene. Cryptic splice site detected, with MaxEntScore 6.5, offset of 36, new splice context is: ttttgggattcatgttgcAGagc. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
PM2
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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;
PP3
?
PP3 - Multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.)
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
?
PP5 - Reputable source recently reports variant as pathogenic, but the evidence is not available to the laboratory to perform an independent evaluation
Variant 2-47480695-G-T is Pathogenic according to our data. Variant chr2-47480695-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2673294.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr2-47480695-G-T is described in Lovd as [Pathogenic].
Likely pathogenic, criteria provided, single submitter
clinical testing
Myriad Genetics, Inc.
Aug 08, 2023
This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -