rs397515879

Positions:

• chr2-47403242-C-A
• chr2-47403242-C-G
• chr2-47403242-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Moderate BP6 BP7

The NM_000251.3(MSH2):​c.51C>A​(p.Val17=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000691 in 1,446,562 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. V17V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000069 (0 hom.)
• Consequence: MSH2 NM_000251.3 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:4
• Conservation: PhyloP100: 0.125

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 Likely_benign. Variant got -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.44).
• BP6: Variant 2-47403242-C-A is Benign according to our data. Variant chr2-47403242-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 186237.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Uncertain_significance=3}.
• BP7: Synonymous conserved (PhyloP=0.125 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MSH2	NM_000251.3	c.51C>A	p.Val17=	synonymous_variant	1/16	ENST00000233146.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MSH2	ENST00000233146.7	c.51C>A	p.Val17=	synonymous_variant	1/16	1	NM_000251.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.0000183 AC: 4 AN: 218502 Hom.: 0 AF XY: 0.0000168 AC XY: 2 AN XY: 119174

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000363

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000308

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000691 AC: 10 AN: 1446562 Hom.: 0 Cov.: 31 AF XY: 0.00000418 AC XY: 3 AN XY: 718364

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000239

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000542

Gnomad4 OTH exome AF: 0.0000334

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000370 Hom.: 0

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2024	MSH2: BP4, BP7 -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Oct 07, 2022	To the best of our knowledge, the variant has not been reported in the published literature. The frequency of this variant in the general population, 0.000031 (3/97280 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. Analysis of this variant using software algorithms for the prediction of the effect of nucleotide changes on MSH2 mRNA splicing yielded predictions that this variant may result in the gain of a cryptic splice site without affecting the natural splice sites . Based on the available information, we are unable to determine the clinical significance of this variant. -

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Dec 05, 2023	The c.51C>A variant (also known as p.V17V), located in coding exon 1 of the MSH2 gene, results from a C to A substitution at nucleotide position 51. This nucleotide substitution does not change the valine at codon 17 but may have some effect on normal mRNA splicing. In silico splice site analysis for this alteration is inconclusive; however, direct evidence is insufficient at this time (Ambry internal data). This nucleotide position is not well conserved in available vertebrate species. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Nov 26, 2018	- -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 01, 2024

This sequence change affects codon 17 of the MSH2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the MSH2 protein. RNA analysis indicates that this variant induces altered splicing and may result in an absent or disrupted protein product. It is unclear whether an alternative in-frame methionine located at codon 26 has the potential to rescue this variant. This variant is present in population databases (rs397515879, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with MSH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 186237). Studies have shown that this variant results in activation of a cryptic splice site and introduces a premature termination codon (Invitae). The resulting mRNA is expected to undergo nonsense-mediated decay. Reports on variants that affect the MSH2 initiator codon, c.1A>C and c.1A>T, indicate that Met26 may serve as an alternate initiator codon (PMID: 21837758, 9718327, 18781192). An experimental study of a recombinant MSH2 protein lacking the first 25 amino acid residues has shown that the truncated protein remains partially functional (PMID: 21837758). The clinical significance of these findings is unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Jul 06, 2017

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Lynch syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

May 31, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.44
CADD	Benign	14
DANN	Benign	0.85
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.16		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: rs397515879; hg19: chr2-47630381;