chr2-47480719-A-AT

Position:

• chr2-47480719-A-AT

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_000251.3(MSH2):​c.2484dup​(p.His829SerfsTer7) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars). Synonymous variant affecting the same amino acid position (i.e. I828I) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MSH2 NM_000251.3 frameshift
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 7.39

Genes affected

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-47480719-A-AT is Pathogenic according to our data. Variant chr2-47480719-A-AT is described in ClinVar as [Pathogenic]. Clinvar id is 433903.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.2484dup	p.His829SerfsTer7	frameshift_variant	15/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.2484dup	p.His829SerfsTer7	frameshift_variant	15/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Malignant tumor of breast Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The MSH2 p.His829Serfsx7 duplication variant was not identified in the literature, nor was it identified in the dbSNP, HGMD, UMD, “Mismatch Repair Genes Variant Database”, “InSiGHT Colon Cancer Database”, “MMR Gene Unclassified Variants Database”, or COSMIC databases. The p.His829Serfsx7 duplication variant is predicted to cause a frameshift, which alters the protein's amino acid sequence beginning at codon 829 and leads to a premature stop codon 7 codons downstream. This alteration is then predicted to result in a truncated or absent protein and loss of function. Loss of function variants of the MSH2 gene are an established mechanism of disease in Lynch syndrome and this is the type of variant expected to cause the disorder. In summary, based on the above information, this variant meets our laboratory’s criteria to be classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1553370324; hg19: chr2-47707858;