2-47478270-A-G

Variant names:

• chr2-47478270-A-G
• rs267608001
• NM_000251.3:c.2211-2A>G

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000251.3(MSH2):​c.2211-2A>G variant causes a splice acceptor, intron 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 (★★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: MSH2 NM_000251.3 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 8.58

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 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-47478270-A-G is Pathogenic according to our data. Variant chr2-47478270-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 433899.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-47478270-A-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MSH2	NM_000251.3	c.2211-2A>G		splice_acceptor_variant, intron_variant	Intron 13 of 15	ENST00000233146.7	NP_000242.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MSH2	ENST00000233146.7	c.2211-2A>G		splice_acceptor_variant, intron_variant	Intron 13 of 15	1	NM_000251.3	ENSP00000233146.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Carcinoma of colon Pathogenic:1

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Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The c.2211-2A>G variant was identified in dbSNP (ID: rs 267608001) “With likely pathogenic allele”. It was not identified in the literature nor was it identified in NHLBI Exome Sequencing Project (Exome Variant Server), Exome Aggregation Consortium (ExAC) database, HGMD, COSMIC, MutDB, “Mismatch Repair Genes Variant Database”, “MMR Gene Unclassified Variants Database”, InSiGHT Colon Cancer Gene Variant Database, “Zhejiang Colon Cancer Database”, the ClinVar database, GeneInsight VariantWire database or UMD databases. The c.2211-2A>G variant is predicted to cause abnormal splicing because the nucleotide substitution occurs in the invariant region of the splice consensus sequence. In addition, 4 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing. In summary, based on the above information, this variant meets our laboratory’s criteria to be classified as pathogenic. -

Hereditary nonpolyposis colon cancer Pathogenic:1

Jun 29, 2022

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: MSH2 c.2211-2A>G is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes a 3 acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251220 control chromosomes (gnomAD). c.2211-2A>G has been reported in the literature in individuals affected with Lynch syndrome, colon cancer, endometrial cancer and urinary tract cancer (Urakami_2018, Ren_2020, Wischhusen_2020, Yamashita_2021). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. A ClinVar submitter (evaluation after 2014) cites the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Lynch syndrome 1 Pathogenic:1

Aug 08, 2023

Myriad Genetics, Inc.

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Hereditary nonpolyposis colorectal neoplasms Pathogenic:1

Dec 15, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Donor and acceptor splice site variants typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in MSH2 are known to be pathogenic (PMID: 15849733, 24362816). This variant has been observed in individual(s) with clinical features of Lynch syndrome (PMID: 29164703, 3258778,18713544). This variant is also known as IVS13-2A>G and g.2211-2A>G in the literature. ClinVar contains an entry for this variant (Variation ID: 433899). This variant is not present in population databases (ExAC no frequency). This sequence change affects an acceptor splice site in intron 13 of the MSH2 gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Nov 21, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2211-2A>G intronic variant results from an A to G substitution two nucleotides upstream from coding exon 14 in the MSH2 gene. This variant (referred to as IVS13-2A>G) has been reported in one individual diagnosed with ureter cancer exhibiting loss of the MSH2 and MSH6 proteins on immunohistochemistry (IHC) and also with colorectal cancer (Urakami S et al. Int J Urol, 2018 02;25:151-156). This variant has been identified in probands whose Lynch syndrome-associated tumor demonstrated loss of MSH2 and MSH6 expression by immunohistochemistry (Li S et al. J. Med. Genet. 2020 Jan;57:62-69; Ren C et al. Cancer Biol Med, 2020 May;17:458-467; Ambry internal data). In silico splice site analysis predicts that this alteration will weaken the native splice acceptor site. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	1.0	D
GERP RS		5.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.21		Position offset: 16
DS_AL_spliceai		0.98		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs267608001; hg19: chr2-47705409;