chr2-47445657-G-A

Variant names:

• chr2-47445657-G-A
• rs587781997
• NM_000251.3:c.1386G>A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000251.3(MSH2):​c.1386G>A​(p.Gln462Gln) variant causes a splice region, synonymous change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MSH2 NM_000251.3 splice_region, synonymous
• Scores: Splicing: ADA: 0.9998
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.20
• Publications: 2 publications found

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]

MSH2 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• Lynch syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• Muir-Torre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• mismatch repair cancer syndrome 2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• ovarian cancer

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• prostate cancer

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• breast cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH2	NM_000251.3	c.1386G>A	p.Gln462Gln	splice_region_variant, synonymous_variant	Exon 8 of 16	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.1386G>A	p.Gln462Gln	splice_region_variant, synonymous_variant	Exon 8 of 16	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1418822 Hom.: 0 Cov.: 24 AF XY: 0.00 AC XY: 0 AN XY: 708690

African (AFR) AF: 0.00 AC: 0 AN: 32522

American (AMR) AF: 0.00 AC: 0 AN: 44548

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25848

East Asian (EAS) AF: 0.00 AC: 0 AN: 39356

South Asian (SAS) AF: 0.00 AC: 0 AN: 84928

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53026

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5678

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1073920

Other (OTH) AF: 0.00 AC: 0 AN: 58996

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Sep 04, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 24, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1386G>A variant (also known as p.Q462Q), located in coding exon 8 of the MSH2 gene, results from a G to A substitution at nucleotide position 1386. This nucleotide substitution does not change the glutamine at codon 462. However, this change occurs in the last base pair of coding exon 8, which makes it likely to have some effect on normal mRNA splicing. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing. RNA studies have demonstrated that this alteration results in an incomplete splice defect; the clinical impact of this abnormal splicing is unknown at this time (Ambry internal data). Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Sep 18, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects codon 462 of the MSH2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the MSH2 protein. This variant also falls at the last nucleotide of exon 8, which is part of the consensus splice site for this exon. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individual(s) with breast cancer (PMID: 35449176). ClinVar contains an entry for this variant (Variation ID: 579844). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.28
CADD	Benign	20
DANN	Benign	0.94
PhyloP100		7.2
Mutation Taster		=6/94	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.99
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs587781997; hg19: chr2-47672796;