rs1553356700

Positions:

• chr2-47429891-AG-A

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1 PM2 PP3_Moderate PP5_Very_Strong

The NM_000251.3(MSH2):​c.1229del​(p.Gly410ValfsTer2) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MSH2 NM_000251.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 2.85

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 20 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
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 2-47429891-AG-A is Pathogenic according to our data. Variant chr2-47429891-AG-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 545842.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.1229del	p.Gly410ValfsTer2	frameshift_variant	7/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.1229del	p.Gly410ValfsTer2	frameshift_variant	7/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 16, 2017	This deletion of one nucleotide in MSH2 is denoted c.1229delG at the cDNA level and p.Gly410ValfsX2 (G410VfsX2) at the protein level. The normal sequence, with the base that is deleted in brackets, is CAGG[delG]TATA. The deletion causes a frameshift which changes a Glycine to a Valine at codon 410, and creates a premature stop codon at position 2 of the new reading frame. This variant is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. MSH2 c.1229delG has not been reported in the literature as a germline variant, to our knowledge, but has been reported as a somatic variant in a microsatellite unstable (MSI-H) colon cancer (Haraldsdottir 2014). We consider this variant to be pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Mar 16, 2020	The variant results in a shift of the reading frame, and is therefore predicted to result in the loss of a functional protein. Not found in the total gnomAD dataset, and the data is high quality. -

Lynch syndrome 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Myriad Genetics, Inc.

Aug 01, 2023

This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 18, 2023

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 545842). This variant has not been reported in the literature in individuals affected with MSH2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Gly410Valfs*2) in the MSH2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MSH2 are known to be pathogenic (PMID: 15849733, 24362816). -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 31, 2020

The c.1229delG pathogenic mutation, located in coding exon 7 of the MSH2 gene, results from a deletion of one nucleotide at nucleotide position 1229, causing a translational frameshift with a predicted alternate stop codon (p.G410Vfs*2). This alteration was identified in the MSI-H tumor of a male diagnosed with ascending colon cancer at age 71 (Haraldsdottir S et al. Gastroenterology, 2014 Dec;147:1308-1316.e1). In silico splice site analysis predicts that this alteration will weaken the native splice donor site and will result in the creation or strengthening of a novel splice donor site. RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.84		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.84		Position offset: 2
DS_DL_spliceai		0.78		Position offset: 50

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

Publications

LitVar

Other links and lift over

dbSNP: rs1553356700; hg19: chr2-47657030;