2-47478382-T-G

Variant names:

• chr2-47478382-T-G
• rs878853811
• NM_000251.3:c.2321T>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_000251.3(MSH2):​c.2321T>G​(p.Ile774Ser) variant causes a missense 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. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I774F) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MSH2 NM_000251.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.64
• Publications: 5 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-47478381-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 408475.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.903

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000251.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MSH2	NM_000251.3	MANE Select	c.2321T>G	p.Ile774Ser	missense	Exon 14 of 16	NP_000242.1
	MSH2	NM_001406674.1		c.2321T>G	p.Ile774Ser	missense	Exon 14 of 18	NP_001393603.1
	MSH2	NM_001406631.1		c.2321T>G	p.Ile774Ser	missense	Exon 14 of 18	NP_001393560.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MSH2	ENST00000233146.7	TSL:1 MANE Select	c.2321T>G	p.Ile774Ser	missense	Exon 14 of 16	ENSP00000233146.2
	MSH2	ENST00000406134.5	TSL:1	c.2321T>G	p.Ile774Ser	missense	Exon 14 of 16	ENSP00000384199.1
	MSH2	ENST00000645506.1		c.2321T>G	p.Ile774Ser	missense	Exon 14 of 17	ENSP00000495455.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Lynch syndrome 1 Uncertain:1

Sep 04, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Lynch syndrome Uncertain:1

Oct 06, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces isoleucine with serine at codon 774 of the MSH2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). This variant does not impact MSH2 function in a 6-thioguanine sensitivity assay in haploid human cells (internally defined LOF score threshold <= -1.32, PMID: 33357406). To our knowledge, this variant has not been reported in individuals affected with MSH2-related disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). A different variant affecting the same codon p.Ile774Val, is considered to be disease-causing (ClinVar variation ID: 408475), suggesting that isoleucine at this position is important for the protein function. The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.

Hereditary nonpolyposis colorectal neoplasms Uncertain:1

Dec 08, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 774 of the MSH2 protein (p.Ile774Ser). This variant is not present in population databases (gnomAD no frequency). 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: 237387). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt MSH2 protein function. This variant disrupts the p.Ile774 amino acid residue in MSH2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 28765196, 33357406; Invitae; external communication). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.49
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.80	D
Eigen	Pathogenic	0.71
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Uncertain	0.59	D
MutationAssessor	Benign	1.9	L
PhyloP100		7.6
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-5.7	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.95	P
Vest4		0.93
MutPred		0.71		Gain of glycosylation at I774 (P = 0.0041)
MVP		0.94
MPC		0.029
ClinPred		0.99	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.95
gMVP		0.94
Mutation Taster		=56/44	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs878853811; hg19: chr2-47705521;